S-2474

(E)-(5)-(3,5-Di-tert-butyl-4-hydroxybenzylidene)-2-ethyl-1,2-isothiazolidine-1,1-dioxide

Shionogi Research Laboratories

cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LO)

mp 135−137 °C.

S-2474,158089-95-3, 158089-96-4 ((Z)-isomer),C20-H31-N-O3-S,

E)-5-(3,5-Di-tert-butyl-4-hydroxybenzylidene)-2-ethylisothiazolidine 1,1-dioxide

• Phenol, 2,6-bis(1,1-dimethylethyl)-4-[(2-ethyl-5-isothiazolidinylidene)methyl]-, S,S-dioxide, (E)-
• 2,6-Bis(1,1-dimethylethyl)-4-[(E)-(2-ethyl-1,1-dioxido-5-isothiazolidinylidene)methyl]phenol
• Phenol, 2,6-bis(1,1-dimethylethyl)-4-[(2-ethyl-1,1-dioxido-5-isothiazolidinylidene)methyl]-, (E)-

(E)-(5)-(3,5-Di-tert-butyl-4-hydroxybenzylidene)-2-ethyl-1,2-isothiazolidine-1,1-dioxide (S-2474, ), which was discovered at Shionogi Research Laboratories, shows potent inhibitory effects on both cyclooxygenase-2 (COX-2) and 5-lipoxygenase (5-LO) and is anticipated to be promising as an antiarthritic drug

synthesis of novel γ-sultam derivatives containing the di-tert-butylphenol antioxidant moiety. Several compounds with lower alkyl groups at the 2-position of the γ-sultam skeleton showed potent inhibitory activities against PGE₂ production via the COX pathway and LTB₄ production via the 5-LO pathway, as well as production of IL-1 in in vitro assays. Extensive pharmacological characterizations revealed that 2-ethyl-γ-sultam derivative 10b displays multiple inhibition of COX, 5-LO, and IL-1 production similar to tenidap and also good selective COX-2 inhibition like NS-398 and celecoxib. It exerted excellent antiinflammatory activity without any ulcerogenic effects and was designated as S-2474 an agent having both NSAID and cytokine modulating properties. S-2474 is now being developed as a promising alternative antiarthritic drug candidate

SYNTHESIS

17th Symp Med Chem (Nov 19 1997 , Tsukuba), EP 0595546; JP 1994211819; US 5418230

The intermediate gamma-sultam (III) was prepared by condensation of 3-chloropropylsulfonyl chloride (I) with ethylamine, followed by cyclization of the resulting chloro sulfonamide (II) under basic conditions. Condensation of 3,5-di- tert-butyl-4- (methoxymethoxy) benzaldehyde (IV) with sultam (III) in the presence of LDA produced the aldol addition compound (V). Then, acid-promoted dehydration and simultaneous methoxymethyl group deprotection gave rise to a mixture of the desired E-benzylidene sultam and the corresponding Z-isomer (VII), which were separated by column chromatography.

PAPER

Novel Antiarthritic Agents with 1,2-Isothiazolidine-1,1-dioxide (γ-Sultam) Skeleton: Cytokine Suppressive Dual Inhibitors of Cyclooxygenase-2 and 5-Lipoxygenase

Various 1,2-isothiazolidine-1,1-dioxide (γ-sultam) derivatives containing an antioxidant moiety, 2,6-di-tert-butylphenol substituent, were prepared. Some compounds, which have a lower alkyl group at the 2-position of the γ-sultam skeleton, showed potent inhibitory effects on both cyclooxygenase (COX)-2 and 5-lipoxygenase (5-LO), as well as production of interleukin (IL)-1 in in vitro assays. They also proved to be effective in several animal arthritic models without any ulcerogenic activities. Among these compounds, (E)-(5)-(3,5-di-tert-butyl-4-hydroxybenzylidene)-2-ethyl-1,2-isothiazolidine-1,1-dioxide (S-2474) was selected as an antiarthritic drug candidate and is now under clinical trials. The structure−activity relationships (SAR) examined and some pharmacological evaluations are described.

http://pubs.acs.org/doi/abs/10.1021/jm9906015

PAPER

Highly E-Selective and Effective Synthesis of Antiarthritic Drug Candidate S-2474 Using Quinone Methide Derivatives

 

PAPER

Development of One-Pot Synthesis of New Antiarthritic Drug Candidate S-2474 with High E-Selectivity

A one-pot synthesis of S-2474 was developed to overcome the problems of a large number of steps, low stereoselectivity, low yield, a large amount of waste, and severe reaction conditions. Aldol-type condensation of 3,5-di-tert-butyl-4-hydroxybenzaldehyde and N-ethyl-γ-sultam was carried out with LDA and then quenched with water. Dehydration proceeded under basic conditions, providing S-2474 directly as a single isomer on the benzylidene double bond. The reaction mechanism appears to involve a quinone methide intermediate. Environmental assessment of the development of this compound is also discussed in this paper.

///////New,  Antiarthritic , Drug Candidate,  S-2474, Shionogi Research Laboratories, cyclooxygenase-2,  (COX-2),  5-lipoxygenase , (5-LO), PHASE 2, 158089-95-3, 158089-96-4, S2474, S 2474

• Supporting Info

CCN2CC\C(=C/c1cc(c(O)c(c1)C(C)(C)C)C(C)(C)C)S2(=O)=O

1H NMR

The 1,3,4-thiadiazole derivatives (2-amino-1,3,4-thiadiazole, acetazolamide, sulfamethizole) have been studied experimentally in the solid state by ¹H–¹⁴N NQDR spectroscopy and theoretically by Density Functional Theory (DFT). The specific pattern of the intra and intermolecular interactions in 1,3,4-thiadiazole derivatives is described within the QTAIM (Quantum Theory of Atoms in Molecules)/DFT formalism. The results obtained in this work suggest that considerable differences in the NQR parameters permit differentiation even between specific pure association polymorphic forms and indicate that the stronger hydrogen bonds are accompanied by the larger η and smaller ν₋ and e²Qq/h values. The degree of π-electron delocalization within the 1,3,4-thiadiazole ring and hydrogen bonds is a result of the interplay between the substituents and can be easily observed as a change in NQR parameters at N atoms. In the absence of X-ray data NQR parameters can clarify the details of crystallographic structure revealing information on intermolecular interactions.

////////////ацетазоламид ,  أسيتازولاميد [,  乙酰唑胺 , ACETAZOLAMIDE

CC(=O)NC1=NN=C(S1)S(N)(=O)=O

Gemfibrozil

5-(2,5-Dimethylphenoxy)-2,2-dimethylpentanoic Acid

IR (KBr, cm^–1): 2959.03, 2919.78, 2877.65, 1709.42, 1613.44, 1586.60, 1511.07, 1473.81, 1414.01, 1387.89, 1317.61, 1286.34, 1271.91, 1214.39, 1159.26, 1048.83, 996.57, 803.75;

¹H NMR (DMSO, 500 MHz, δ ppm): 1.12 (s, 6H), 1.60 and 1.67 (m, 4H), 2.08 (s, 3H), 2.24 (s, 3H), 3.90 (t, 2H), 6.62 (d, 1H), 6.70 (s, 1H), 6.97 (d, 1H);

¹³C NMR and DEPT (DMSO, 500 MHz, δ ppm): 15.39 (CH₃), 20.94 (CH₃), 24.67 (CH₂), 24.87 (CH_3, CH₃), 36.43 (CH₂), 40.91 (C), 67.57 (CH₂), 112.07 (CH), 120.45 (CH), 122.44 (C), 129.96 (CH), 135.93 (C), 156.43 (C), 178.56 (C);

MS M/_Z (ESI): 251.16 [(MH)⁺].

Solvent:CDCl3Instrument Type:JEOLNucleus:1HFrequency:400 MHzChemical Shift Reference:TMS

¹H NMR spectrum of C₁₅H₂₂O₃ in CDCL3 at 400 MHz

Gemfibrozil is the generic name for an oral drug used to lower lipid levels. It belongs to a group of drugs known as fibrates. It is most commonly sold as the brand name, Lopid. Other brand names include Jezil and Gen-Fibro.

Gemfibrozil was selected from a series of related compounds synthesized in the laboratories of the American company Parke Davisin the late 1970s. It came from research for compounds that lower plasma lipid levels in humans and in animals.^[1]

Actions

• Is an activator of peroxisome proliferator-activated receptor-alpha (PPARα), a nuclear receptor that is involved in metabolism ofcarbohydrates and fats, as well as adipose tissue differentiation. This increase in the synthesis of lipoprotein lipase thereby increases the clearance of triglycerides.^{[citation needed]}

Therapeutic effects

• Reduce triglyceride levels ^[2]
• Reduce very low density lipoprotein (VLDL) levels
• Modest reduction of low density lipoprotein (LDL) levels
• Moderate increase in high density lipoprotein (HDL) levels

Nontherapeutic effects and toxicities

• GI distress
• Musculoskeletal pain
• Increased incidence of gallstone
• Hypokalemia (low blood potassium)
• Increased risk of cancer

Indications

• Hyperlipidemia (Type III): Gemfibrozil is the drug of choice for therapy.
• Hypertriglyceridemia (Type IV): Gemfibrozil, though not as effective as niacin, is better tolerated.^{[citation needed]}

Contraindications and precautions

• Gemfibrozil should not be given to these patients:
  • Hepatic dysfunction
• Gemfibrozil should be used with caution in these higher risk categories:
  • Biliary tract disease
  • Renal dysfunction
  • Pregnant women
  • Obese patients

Drug interactions

• Anticoagulants: Gemfibrozil potentiates the action of warfarin and indanedione anticoagulants.^{[citation needed]}
• Statin drugs: Concomitant administration of fibrates (including gemfibrozil) with statin drugs increases the risk of muscle cramping, myopathy, andrhabdomyolysis.
• Gemfibrozil inhibits the activation of the liver’s Cytochrome P450 system, reducing hepatic metabolism of many drugs, and prolonging their half lives and duration of action.
  • Drugs metabolized by the Cytochrome P450 system include:
    • Many antidepressants
    • Many antipsychotics
    • Many antiepileptics
    • Theophylline and other methylxanthine drugs
    • Several anesthetic agents
    • Oral contraceptive pills
    • Statins
    • Warfarin

Environmental data

Gemfibrozil has been detected in biosolids (the solids remaining after wastewater treatment) at concentrations up to 2650 ng/g wet weight.^[3] This indicates that it survives the wastewater treatment process.

SYNTHESIS

The sodium isobutyrate (I) is metallated with lithium diisopropylamide, and the resulting compound is alkylated with 3- (2,5-dimethylphenoxy) propyl bromide.

PATENT

Paul, L. C. 2,2-Dimethyl-ω-aryloxy alkanoic acids and salts and ester thereof. U.S. 3,674,836, 1972.

http://www.google.co.in/patents/US3674836

CLIP

Production of Gemfibrozil
(1)2,5-Dimethylphenol and 1-Bromo-3-chloropropane reaction of 1-(2,5-dimethylphenoxy)-3-chloropropane. The reaction is carried out in toluene, adding new clean off reflux 5h. Just as follows:

(2)N/A can be used to manufacture Gemfibrozil.

PAPER

Improved Process for Preparation of Gemfibrozil, an Antihypolipidemic

An improved process for the preparation of gemfibrozil, an antihypolipodimic drug substance, with an overall yield of 80% and ∼99.9% purity (including three chemical reactions) is reported. Formation and control of possible impurities are also described. Finally, gemfibrozil is isolated from water without any additional solvent purification.

Literature References:

Serum lipid regulating agent. Prepn: P. L. Creger, DE 1925423; eidem, US 3674836 (1969, 1972, both to Parke, Davis).

Production: O. P. Goel, US 4126637 (1978 to Warner-Lambert).

Pharmacology: A. H. Kissebach et al.,Atherosclerosis 24, 199 (1976); M. T. Kahonen et al., ibid. 32, 47 (1979).

Series of articles on metabolism, clinical pharmacology, kinetics and toxicology: Proc. R. Soc. Med. 69, Suppl 2, 1-120 (1976).

Toxicity data: S. M. Kurtz et al., ibid. 15.

Clinical trial in hyperlipidemia: J. E. Lewis et al., Pract. Cardiol. 9, 99 (1983).

Clinical reduction of cardiovascular risk in patients with low HDL levels: H. B. Rubins et al., N. Engl. J. Med. 341, 410 (1999).

References

External links

• DrugBank Gemfibrozil
• NIH Gemfibrozil Drug Info
• Lopid International Study
• Author (2004). “Safety of Statins”. Circulation. 109: III–50–III–57. doi:10.1161/01.cir.0000131519.15067.1f.
• http://www.ihs.gov/nptc/documents/NPTC%20Lipid%20Review.pdf

Gemfibrozil

Systematic (IUPAC) name
5-(2,5-dimethylphenoxy)-2,2-dimethyl-pentanoic acid
Clinical data
Trade names	Lopid
AHFS/Drugs.com	Monograph
MedlinePlus	a686002
Pregnancy category	Category C
Routes of administration	Oral
Legal status
Legal status	By Prescription
Pharmacokinetic data
Bioavailability	Close to 100%
Protein binding	95%
Metabolism	Hepatic (CYP3A4)
Biological half-life	1.5 hours
Excretion	Renal 94% Feces 6%
Identifiers
CAS Number	25812-30-0
ATC code	C10AB04 (WHO)
PubChem	CID 3463
IUPHAR/BPS	3439
DrugBank	DB01241
ChemSpider	3345
UNII	Q8X02027X3
KEGG	D00334
ChEBI	CHEBI:5296
ChEMBL	CHEMBL457
Chemical data
Formula	C15H22O3
Molar mass	250.333 g/mol

LOPID® (gemfibrozil tablets, USP) is a lipid regulating agent. It is available as tablets for oral administration. Each tablet contains 600 mg gemfibrozil. Each tablet also contains calcium stearate, NF; candelilla wax, FCC; microcrystalline cellulose, NF; hydroxypropyl cellulose, NF; hypromellose, USP; methylparaben, NF; Opaspray white; polyethylene glycol, NF; polysorbate 80, NF; propylparaben, NF; colloidal silicon dioxide, NF; pregelatinized starch, NF. The chemical name is 5-(2,5-dimethylphenoxy)2,2-dimethylpentanoic acid, with the following structural formula:

The empirical formula is C₁₅H₂₂O₃ and the molecular weight is 250.35; the solubility in water and acid is 0.0019% and in dilute base it is greater than 1%. The melting point is 58° –61°C. Gemfibrozil is a white solid which is stable under ordinary conditions.

/////////Gemfibrozil,  Antilipemic,  Fibrates, 25812-30-0,

CC1=CC(OCCCC(C)(C)C(O)=O)=C(C)C=C1

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https://www.facebook.com/Indoco-Remedies-Limited-India-317944458228011/

USFDA approves Indoco’s Allopurinol ANDA… Indoco Remedies Limited (India)’s … Indoco Remedies Limited (India) added a new photo

Allopurinol, sold under the brand name Zyloprim and generics, is a medication used primarily to treat excess uric acid in the bloodand its complications, including chronic gout. It is a xanthine oxidase inhibitor and is administered orally.

It is on the World Health Organization’s List of Essential Medicines, a list of the most important medication needed in a basic health system.

Allopurinol has been marketed in the United States since August 19, 1966, when it was first approved by FDA under the trade name Zyloprim. Allopurinol was marketed at the time by Burroughs-Wellcome. Allopurinol is now a generic drug sold under a variety of brand names, including Allohexal, Allosig, Milurit, Alloril, Progout, Ürikoliz, Zyloprim, Zyloric, Zyrik, and Aluron

Aditi Kare Panandikar, Managing Director, Indoco Remedies

click above

///////////Indoco Remedies Ltd, USFDA,  approves,  Indoco’s,  Allopurinol,  ANDA, Aditi Kare Panandikar, Managing Director,

Scaling up from mg to Kgs – Making your First GMP Batch 

6th – 7th October 2016, Clearwater, USA

“the course was very informative and it allowed me to see the big picture from discovery stage to pilot plant” 
Genentech

Course Outline:

• Introduction
• Making the first 100g non-GMP Batch
• Non-GMP vs GMP preparation
• Physical version and form
• Process safety and raw materials supply
• Scaling into fixed vessels
• Technology transfer
• Genotoxic impurities
• Case studies and Review

Who should attend:

• Project managers
• Project leaders
• Bench chemists
• New starters
• MedChem Support teams

This course aims to provide attendees with a good understanding of the issues involved taking development candidates to the first in human trials.

Click here to Download the Course Brochure

Presented by Dr John Knight, JKonsult Ltd

Click here to Download the Course Brochure

“Brilliant Course, learn lots of tips and tricks”
Vertex
“First incursion into Chemical Development has been very, very educational. John’s way of explaining the material has been wonderful.”
Almirall

Arformoterol is a long-acting β₂ adrenoreceptor agonist (LABA) indicated for the treatment of chronic obstructive pulmonary disease(COPD). It is sold by Sunovion, under the trade name Brovana, as a solution of arformoterol tartrate to be administered twice daily (morning and evening) by nebulization.^[1]

Arformoterol inhalation solution, a long-acting beta2-adrenoceptor agonist, was launched in the U.S. in 2007 for the long-term twice-daily (morning and evening) treatment of bronchospasm in patients with chronic obstructive pulmonary disease (COPD), including chronic bronchitis and emphysema. The product, known as Brovana(TM), for use by nebulization only, is the first long-acting beta2-agonist to be approved as an inhalation solution for use with a nebulizer. The product was developed and is being commercialized by Sunovion Pharmaceuticals (formerly Sepracor)

It is the active (R,R)-(−)-enantiomer of formoterol and was approved by the United States Food and Drug Administration (FDA) on October 6, 2006 for the treatment of COPD.

Arformoterol is a bronchodilator. It works by relaxing muscles in the airways to improve breathing. Arformoterol inhalation is used to prevent bronchoconstriction in people with chronic obstructive pulmonary disease, including chronic bronchitis and emphysema. The use of arformoterol is pending revision due to safety concerns in regards to an increased risk of severe exacerbation of asthma symptoms, leading to hospitalization as well as death in some patients using long acting beta agonists for the treatment of asthma.

Arformoterol tartrate

• Molecular FormulaC₂₃H₃₀N₂O₁₀
• Average mass494.492
•  cas 200815-49-2
• 183-185°C

 

SYNTHESIS

PATENT

us-9309186

Example 1

Synthesis of (R,R)-Formoterol-L-tartrate Form D

A solution containing 3.9 g (26 mmol) of L-tartaric acid and 36 mL of methanol was added to a solution of 9 g (26 mmol) of arformoterol base and 144 mL methanol at 23.degree. C. Afterwards, the resulting mixture was seeded with form D and stirred at 23.degree. C. for 1 hour. It was then further cooled to 0-5.degree. C. for 1 hour and the product collected by filtration and dried under inlet air (atmospheric pressure) for 16 hours to provide 11.1 g (86% yield) (99.7% chemical purity, containing 0.14% of the degradation impurity (R)-1-(3-amino-4-hydroxyphenyl)-2-[[(1R)-2-(4-methoxyphenyl)-1-methylethy- l]amino]ethanol) of (R,R)-formoterol L-tartrate form D, as an off white powder. .sup.1H-NMR (200 MHz, d.sub.6-DMSO) .delta.: 1.03 (d, 3H); 2.50-2.67 (m, 5H); 3.72 (s, 3H); 3.99 (s, 2H); 4.65-4.85 (m, 1H); 6.82-7.15 (m, 5H); 8.02 (s, 1H); 8.28 (s, 1H); 9.60 (s, NH). No residual solvent was detected (.sup.1H-NMR).

PSD: d.sub.50=2.3 .mu.m.

 

Taking Advantage of Polymorphism To Effect an Impurity Removal:  Development of a Thermodynamic Crystal Form of (R,R)-FormoterolTartrate

Gerald J. Tanoury ,*^† Robert Hett , Donald W. Kessler , Stephen A. Wald , and Chris H. Senanayake *^‡

Chemical Research and Development, Sepracor Inc., 111 Locke Drive, Marlborough, Massachusetts 01752, U.S.A.

Org. Proc. Res. Dev., 2002, 6 (6), pp 855–862

DOI: 10.1021/op025531h

 http://pubs.acs.org/doi/abs/10.1021/op025531h

Abstract

The development and large-scale implementation of a novel technology utilizing polymorphic interconversion and crystalline intermediate formation of (R,R)-formoterol l-tartrate ((R,R)-FmTA, 1) as a tool for the removal of impurities from the final product and generation of the most thermodynamically stable crystal form is reported. The crude product was generated by precipitation of the free base as the l-tartrate salt in a unique polymorphic form, form B. Warming the resultant slurry effected the formation of a partially hydrated stable crystalline intermediate, form C, with a concomitant decrease in the impurity levels in the solid. Isolation and recrystallization of form C provided 1 in the thermodynamically most stable polymorph, form A.

PATENT

Compound (R, R)-1-(4-Benzyloxy-3-nitro-phenyl)-2-[[2-(4-methoxy-phenyl)-1-methylethyl]-(1-phenyl-ethyl)-amino]-ethanol (compound VI), having the configuration represented by the following formula:

PATENT

Scheme

Scheme

Formoterol is a long-acting β₂-adrenoceptor agonist and has a long duration of action of up to 12 hours. Chemically it is termed as Λ/-[2-hydroxy-5-[1-hydroxy-2-[[2-(4- methoxyphenyl)propan-2-yl]amino]ethyl]phenyl]-formamide. The structure of formoterol is as shown below.

The asterisks indicate that formoterol has two chiral centers in the molecule, each of which can exist in two possible configurations. This gives rise to four diastereomers which have the following configurations: (R,R), (S₁S), (S₁R) and (R₁S).

(R₁R) and (S₁S) are mirror images of each other and are therefore enantiomers. Similarly (S₁R) and (R₁S) form other enatiomeric pair.

The commercially-available formoterol is a 50:50 mixture of the (R₁R)- and (S₁S)- enantiomers. (R,R)-formoterol is an extremely potent full agonist at the β_2-adrenoceptor and is responsible for bronchodilation and has anti-inflammatory properties. On the other hand (S,S)-enantiomer, has no bronchodilatory activity and is proinflammatory.

Murase et al. [Chem.Pharm.Bull., .26(4)1123-1129(1978)] synthesized all four isomers of formoterol and examined for β-stimulant activity. In the process, racemic formoterol was subjected to optical resolution with tartaric acid.

In another attempt by Trofast et al. [Chirality, 3:443-450(1991 )], racemic 4-benzyloxy-3- nitrostryrene oxide was coupled with optically pure N-[(R)-1-phenylethyl]-2-(4- methoxyphenyl)-(R)1-methylethylamine to give diastereomeric mixtures of intermediates, which were separated by column chromatography and converted to the optically pure formoterol.

In yet another attempt, racemic formoterol was subjected to separation by using a chiral compound [International publication WO 1995/018094].

WO 98/21175 discloses a process for preparing optically pure formoterol using optically pure intermediates (R)-N-benzyl-2-(4-methoxyphenyl)-1-methylethyl amine and (R)-4- benzyloxy-3-formamidostyrene oxide.

Preparation of optically pure formoterol is also disclosed in IE 000138 and GB2380996.

 

 PAPER

Diethylanilineborane:  A Practical, Safe, and Consistent-Quality Borane Source for the Large-Scale Enantioselective Reduction of a Ketone Intermediate in the Synthesis of (R,R)-Formoterol

H. Scott Wilkinson , Gerald J. Tanoury ,*^† Stephen A. Wald , and Chris H. Senanayake *

Chemical Research and Development, Sepracor Incorporated, 111 Locke Drive, Marlborough, Massachusetts 01752, U.S.A.

Org. Proc. Res. Dev., 2002, 6 (2), pp 146–148

DOI: 10.1021/op015504b

http://pubs.acs.org/doi/abs/10.1021/op015504b

Abstract

The development of a process for the use of N,N-diethylaniline−borane (DEANB) as a borane source for the enantioselective preparation of a key intermediate in the synthesis of (R,R)-formoterol l-tartrate, bromohydrin 2, from ketone 3 on kilogram scale is described. DEANB was found to be a more practical, safer, and higher-quality reagent when compared to other more conventional borane sources:  borane−THF and borane−DMS.

PAPER

http://nopr.niscair.res.in/bitstream/123456789/8917/1/IJCB%2044B(1)%20167-169.pdf

PAPER

http://www.bioorg.org/down/Hetetorcycles_07_2243.pdf?ckattempt=1

PAPER

Arformoterol: (R,R)-eformoterol, (R,R)-formoterol, arformoterol tartrate, eformoterol-sepracor, formoterol-sepracor, R,R-eformoterol, R,R-formoterol.

CLIP

PAPER

doi:10.1016/j.cclet.2008.01.012

http://www.sciencedirect.com/science/article/pii/S1001841708000132

Chinese Chemical Letters

Volume 19, Issue 3, March 2008, Pages 279–280

Abstract

(R)-1-(4-Methoxyphenyl)propan-2-amine 2a, an optical active intermediate for (R,R)-formoterol, was synthesized from d-alanine in 65% overall yield by using a simple route, which contained protecting amino group, cyclization, coupling with Grignard reagent, reduction and deprotection.

References

External links

• Brovana website

Arformoterol

Systematic (IUPAC) name
N-[2-hydroxy-5-[(1R)-1-hydroxy-2-[[(2R)-1-(4-methoxyphenyl) propan-2-yl]amino]ethyl] phenyl]formamide
Clinical data
Trade names	Brovana
AHFS/Drugs.com	Monograph
MedlinePlus	a602023
License data	US FDA: Arformoterol
Pregnancy category	US: C (Risk not ruled out)
Routes of administration	Inhalation solution fornebuliser
Legal status
Legal status	US: ℞-only
Pharmacokinetic data
Protein binding	52–65%
Biological half-life	26 hours
Identifiers
CAS Number	67346-49-0
ATC code	none
PubChem	CID 3083544
IUPHAR/BPS	7479
DrugBank	DB01274
ChemSpider	2340731
UNII	F91H02EBWT
ChEBI	CHEBI:408174
ChEMBL	CHEMBL1201137
Chemical data
Formula	C19H24N2O4
Molar mass	344.405 g/mol

Formoterol

//////Arformoterol, (R,R)-Formoterol, (R,R)-Formoterol-L-(+)-tartrate, 200815-49-2, Arformoterol tartrate , Brovana, UNII:5P8VJ2I235, Sepracor, Asthma Therapy, Bronchodilators, Chronic Obstructive Pulmonary Diseases, COPD ,  RESPIRATORY DRUGS, beta2-Adrenoceptor Agonists, Phase III, 2007, Sunovion

COC1=CC=C(C[C@@H](C)NC[C@H](O)C2=CC(NC=O)=C(O)C=C2)C=C1

Acting on the publication of the ICH Q7 Q&A Document in June last year APIC has decided to elaborate another revision of its “ICH Q7 How to do Document” taking into account these Q&As. Here you will get to know why this upcoming How to do Document is a valuable support for API and API intermediate manufacturers regarding the practical implementation of the ICH Q7 What to do principles.

see

http://www.gmp-compliance.org/enews_05493_APIC-is-working-on-an-enhanced-ICH-Q7-How-to-do-Guide_15332,S-WKS_n.html

The first edition of the “How to do Document – Interpretation of the ICH Q7 Guide” was published by APIC shortly after the ICH Q7 Guideline appeared as Step 4 document in November 2000. In the meantime it has undergone a numer of revisions and the current version of the How to do Document to be found on the publications section of APIC’s website is an update from August 2015 (version 8). This document was written by experts from the European Industry (CEFIC APIC) and is essentially an interpretation of “how to” implement the requirements of the ICH Q7 Guide based on practical experience.

On the occasion of the publication of the ICH Q7 Questions & Answers Document in June 2015 another revision of APIC’s How to do Document was necessary. APIC is currently working on this new revision (version 9) taking into account the new ICH Q7 Q&A Document which will be incorporated into the How to do Document as a new chapter 21. In this chapter each Question/Answer of the Q&A document is examined and commented with respect to its practical implementation. The following example illustrates what these practical comments look like:

ICH Q7 Q&A – Question
For dedicated equipment, is ‘visually clean’ acceptable for verification of cleaning effectiveness, (i.e., no expectation for specific analytical determination)?

ICH Q7 Q&A – Answer
‘Visually clean’ may be acceptable for dedicated equipment based on the ability to visually inspect and sufficient supporting data from cleaning studies (e.g., analytical determination to demonstrate cleaning effectiveness) [ICH Q7, Section 12.76]. Equipment should be cleaned at appropriate intervals (e.g., time or number of batches) to prevent build-up and carryover of contaminants (e.g., degradants or objectionable levels of microorganisms) so that they do not adversely alter the quality of the API [ICH Q7, Sections 5.23, 12.7].

Comment in APIC’s How to do Document
“dedicated equipment” can be defined in various ways such as:
– a reactor that is used solely for 1 API process
– a reactor used for different intermediate steps of the same API.
– a reactor used for different steps in the same intermediate or API
– a reactor solely used for 1 stage in 1 process
Whatever definition is used it should be documented and justified.
When visual inspection is applied following points should be considered:
– adequate lighting
– fully dried
– difficult to clean spots visually inspectable
– use of cameras, endoscopy
– limit of detection of visual cleanliness
– dirty hold time / clean hold time
– Campaign length

While the purpose of the ICH Q7 Q&A Document is to clarify some equivocal issues of the ICH Q7 Guideline the comments of APIC’s ICH Q7 Q&A How to do Document intend to give support on an even more practical level. So after its finalisation and publication later this year the API industry will have another very useful document available which facilitates the implementation of the ICH Q7 principles.

At the pre-Conference Session to the 19th APIC/CEFIC European Conference on Active Pharmaceutical Ingredients on 22 November 2016 in Barcelona APIC will launch the ICH Q7 Q&A How to do Document as a stand alone document. All participants will receive a copy.
///////////////

The World Health Organizaton (WHO) recently published a new Annex 10 on handling of variations. Find out more about the new WHO general guidance on variations to multisource pharmaceutical products.

see http://www.gmp-compliance.org/enews_05425_New-WHO-guidance-on-variations-to-multisource-pharmaceutical-products_15152,15173,Z-RAM_n.html

The World Health Organizaton recently published a new Annex 10: WHO general guidance on variations to multisource pharmaceutical products.

The document is “intended to serve as a guide for establishing national requirements for the regulation of post-approval changes.” Proposed categories and reporting procedures are provided. Modifications may be justified in light of risk-benefit and legal considerations specific to each national medicines regulatory authority (NMRA).

The guideline can be used with respect to changes to the quality sections of product dossiers and should be read in context with the Guidelines on submission of documentation for a multisource (generic) finished product: quality part as well as other related WHO guidelines or applicable national guidelines.

The guideline emphasizes that “even well-resourced agencies find it difficult to evaluate all the pharmaceutical changes that are made to all products.” Therefore, “a shift towards increased self-assessment of changes by the marketing authorization (MA) holder” has been observed. In this context “it is necessary, to define those changes that can be made without the NMRA´s prior approval (self-assessable changes) and those that require prior approval based on an understanding of the risk and how best to manage the risk.”

Description of the reporting categories are discussed in section 5 of the Annex:

• Notifications: They can be made for changes to the product that may have no potential or minimal potential to have a negative impact on the quality, safety and efficacy (QSE) of a finished pharmaceutical product (FPP). Implementation of such variations may be possible without prior approval by the NMRA (e.g. submission of these variations as annual notifications).
• Minor variations: Changes with moderate or negative impact on the QSE. Such changes must be submitted to the NMRA with all required documentation prior to implementation. The MA holder may implement the change if no objection has been issued within a specific time period by the NMRA.
• Major variations: They have a significant potential to have a negative impact on the QSE. A major variation should be reviewed and approved by the NMRA prior to implementation of the change. To increase the efficiency NMRAs may accept grouping of variations under specific circumstances (see also FDA´s new policy regarding grouping of CMC changes).
• Editorial changes: They typically need not to be submitted and can be included as a notification together with a subsequent variation concerning that part of the dossier.

Certain changes can be so fundemental that they require a submission of a new dossier. Examples of such changes are:

• Change of the API to a different API,
• Inclusion of an additional API in a multicomponent product,
• Removal of one API from a multicomponent product,
• Change in the dose and/ or strength of one or more APIs,
• Change from an immediate-release product to an extended- or delayed-release dosage form or vice versa,
• Change from a liquid to a powder for reconstitution or vice versa,
• Changes in the route of administration.

For any change in the SmPC, patient information leaflet (PIL)  and/or labels the NMRAS should be notified and submission of the revised product information and/or labelling is expected as per country-specific requirements.

Proposed recommendations on the regulatory procedures for the reporting of changes to the NMRA are discussed in section 8 of the Annex:

• General: It is essential that different branches of the NMRA interact and exchange information effectively. They should, for example, discuss whether a change may require a GMP inspection or may be reviewed during the next routine inspection.
• Presubmission meetings: Procedures should be established to allow MA holders the opportunity to obtain advice prior to submitting variations.
• Proposed documentation for minor variations: Basic information like
  – covering letter,
  – application form,
  – a list of subsections of the current dossier affected by the change(s),
  – a list and description of each change, reason for change(s) and the date each change was implemented,
  – relevant summary of data from studies and tests performed,
  – copies of the updated subsections of the original dossier,
  should be included as part of the immediate or annual notification, where prior approval is not required.
• Proposed documentation for variations requiring prior approval: Additionally to the documents mentioned under “minor variations”:
  – replacement of the relevant subsections of the dossier in accordance with the acceptable dossier format for the NMRAs concerned, with the proposed changes clearly annotated,
  – copies of the SmPC, PIL and labels, if relevant,
  – registration status and date of the proposed change(s) in other countries and/or agencies that have already approved the variation(s), especially the country of origin and the reference agencies.
• Review procedures: NMRA should adopt a risk-based review strategy for assessment, concentratiing most effort on those changes considered to carry the greatest risk. NMRA may consider whether it will rely on decisions and/or assessment reports made by other national authorities or prepare its own full assessment report or use a combination of those approaches.

For more Information please see the new Annex 10 – WHO general guidance on variations to multisource pharmaceutical products.

//////////////Annex 10,  WHO general guidance, multisource pharmaceutical products.

Eribulin

Eribulin mesylate

エリブリンメシル酸塩

CAS 441045-17-6 MESYLATE

C₄₁H₆₃NO₁₄S, 826.00222 g/mol

halichrondrin B analog, B1939, E7389, ER-086526,Halaven

CAS 253128-41-5  FREE FORM

(1S,3S,4R)-3-tert-butoxycarbonylamino-4-hydroxycyclopentanecarboxylic acid methyl ester;

(1S,3S,6S,9S,12S,14R,16R,18S,20R,21R,22S,26R,29S,31R,32S,33R,35R,36S)-20-[(2S)-3-Amino-2-hydroxypropyl]-21-methoxy-14-methyl-8,15-bis(methylene)-2,19,30,34,37,39,40,41-octaoxanonacyclo[24.9.2.13,32.13,33.16,9.112,16.018,22.029,36.031,35]hentetracontan-24-one;

2-(3-Amino-2-hydroxypropyl)hexacosahydro-3-methoxy- 26-methyl-20,27-bis(methylene)11,15-18,21-24,28-triepoxy- 7,9-ethano-12,15-methano-9H,15H-furo(3,2-i)furo(2′,3′-5,6) pyrano(4,3-b)(1,4)dioxacyclopentacosin-5-(4H)-one

(2R,3R,3aS,7R,8aS,9S,10aR,11S,12R,13aR,13bS,15S,18S,21S,24S,26R,28R,29aS)-2-((2S)-3-amino-2-hydroxypropyl)-3-methoxy-26-methyl-20,27-dimethylidenehexacosahydro-11,15:18,21:24,28-triepoxy-7,9-ethano-12,15-methano-9H,15H-furo(3,2-i)furo(2′,3′:5,6)pyrano(4,3-b)(1,4)dioxacyclopentacosin-5(4H)-one methanesulfonate (salt)

11,15:18,21:24,28-Triepoxy-7,9-ethano-12,15-methano-9H,15H-furo(3,2-i)furo(2′,3′:5,6)pyrano(4,3-b)(1,4)dioxacyclopentacosin-5(4H)-one, 2-((2S)-3- amino-2-hydroxypropyl)hexacosahydro-3-methoxy-26-methyl-20,27-bis(methylene)-, 2R,3R,3aS,7R,8aS,9S,10aR,11S,12R,13aR,13bS,15S,18S,21S,24S,26R,28R,29aS)-, methanesulfonate (salt)

エリブリンメシル酸塩
Eribulin Mesilate

C₄₀H₅₉NO₁₁CH₄O₃S : 826
[441045-17-6]

Eribulin mesylate is the mesylate salt of a synthetic analogue of halichondrin B, a substance derived from a marine sponge (Lissodendoryx sp.) with antineoplastic activity.

E7389 is the mesylate salt of a synthetic analogue of halichondrin B, a substance derived from a marine sponge (Lissodendoryx sp.) with antineoplastic activity. Eribulin binds to the vinca domain of tubulin and inhibits the polymerization of tubulin and the assembly of microtubules, resulting in inhibition of mitotic spindle assembly, induction of cell cycle arrest at G2/M phase, and, potentially, tumor regression.

Halichondrin B, a large polyether macrolide, was isolated 25 years ago from the marine sponge Halichondria okadai

ERBULIN

The anti-cancer drug made from a sea-spongeEribulin is an anticancer drug marketed by Eisai Co. under the trade name Halaven. Eribulin mesylate was approved by the U.S. Food and Drug Administration on November 15, 2010, to treat patients with metastatic breast cancer who have received at least two prior chemotherapy regimens for late-stage disease, including both anthracycline– and taxane-based chemotherapies.^[1] It was approved by Health Canada on December 14, 2011 for treatment of patients with metastatic breast cancer who have previously received at least two chemotherapeutic regimens for the treatment of metastatic disease. ^[2]

Eribulin is also being investigated by Eisai Co. for use in a variety of other solid tumors, including non-small cell lung cancer, prostate cancer and sarcoma.^[3]

Eribulin has been previously known as E7389 and ER-086526, and also carries the US NCI designation NSC-707389.

Eribulin mesylate is an analogue of halichondrin B, which in 1986 was isolated from the marine sponge Halichondria okadai toxic Pacific.Halichondrin B has a significant anti-tumor activity. The Eribulin synthetically obtained has a simpler but still complex molecular structure.Taxanes such as to inhibit the spindle apparatus of the cell, but it is engaged in other ways.

Drug substance, eribulin mesylate, is a It is a structurally simplified synthetic analogue of halichondrin B, a natural product isolated from the marine sponge Halichondira okadai. Eribulin mesylate is a white powder which is freely soluble in water, methanol, ethanol, 1-octanol, benzyl alcohol, dichloromethane, dimethylsulfoxide, N-methylpyrrolidone and ethyl acetate. It is soluble in acetone, sparingly soluble in acetonitrile, and practically insoluble in tertbutyl methyl ether, n-heptane and n-pentane. Eribulin mesylate is characterized by ion chromatography for counter ion content, and spectroscopic analyses (mass, ultraviolet, nuclear magnetic resonance, single crystal X-ray crystallography, and circular dichroism) for molecular structure and absolute configuration. Bulk drug substance is hygroscopic and sensitive to light, heat, and acid hydrolysis,,,,,,……..http://www.accessdata.fda.gov/drugsatfda_docs/nda/2010/201532orig1s000chemr.pdf

Melvin Yu received his B.S. from MIT, and both his M.A. and Ph.D. degrees from Harvard University while studying under Professor Yoshito Kishi. In 1985, he joined Eli Lilly, and in 1993 he relocated to Eisai Inc. where he led the chemistry team that discovered Halaven. He was then responsible for the initial route nding and synthesis scale-up effort that ultimately provided the rst multi-gram batch of eribulin mesylate. Mel retains a strong interest in natural products as the inspiration of new chemotherapeutic agents, and in this context recently expanded his area of research to include cheminformatics and compound library design.

Wanjun Zheng received a Ph.D. in organic chemistry from Wesleyan University in 1994 under the direction of Professor Peter A. Jacobi working on synthetic methodology development and its application in natural product synthesis. He spent over two years as a postdoctoral research fellow in Harvard University under Professor Yoshito Kishi working on the complete structure determination of maitotoxin. He joined Eisai in 1996 and has since been contributing and leading many drug discovery projects including project in the discovery of Halaven.

Boris M. Seletsky earned his PhD in 1987 from Shemyakin Institute of Bioorganic Chemistry in Moscow, Russia working on new methods in steroid synthesis under direction of Dr George Segal and Professor Igor Torgov. Aer several years of natural product research at the same Institute, he moved on to postdoctoral studies in stereoselective synthesis with Professor Wolfgang Oppolzer at the University of Geneva, Switzerland, and Professor James A. Marshall at the University of South Carolina. Boris joined Eisai in 1994, and has contributed to many oncology drug discovery projects with considerable focus on natural products as chemical leads, culminating in the discovery of Halaven.

PAPER

http://www.sciencedirect.com/science/article/pii/S0960894X0401100X

Volume 14, Issue 22, 15 November 2004, Pages 5551–5554

Macrocyclic ketone analogues of halichondrin B

• Wanjun Zheng^a,
• Boris M. Seletsky^a,
• Monica H. Palme^a,
• Paul J. Lydon^a,
• Lori A. Singer^a,
• Charles E. Chase^a,
• Charles A. Lemelin^a,
• Yongchun Shen^a,
• Heather Davis^a,
• Lynda Tremblay^a,
• Murray J. Towle^b,
• Kathleen A. Salvato^b,
• Bruce F. Wels^b,
• Kimberley K. Aalfs^b,
• Yoshito Kishi^c,
• Bruce A. Littlefield^b,
• Melvin J. Yu^{a, ,}

• ^a Department of Medicinal Chemistry, Eisai Research Institute, 4 Corporate Drive, Andover, MA 01810, USA
• ^b Department of Anticancer Research, Eisai Research Institute, 4 Corporate Drive, Andover, MA 01810, USA
• ^c Advisory Board, Eisai Research Institute, 4 Corporate Drive, Andover, MA 01810, USA

doi:10.1016/j.bmcl.2004.08.069

PAPER

Melvin J. Yu,*^a   Wanjun Zheng^a and   Boris M. Seletsky^a  

*Corresponding authors

^aEisai Inc., Andover, USA
E-mail: Melvin_Yu@eisai.com

Nat. Prod. Rep., 2013,30, 1158-1164

DOI: 10.1039/C3NP70051H, http://pubs.rsc.org/is/content/articlelanding/2013/np/c3np70051h#!divAbstract

Covering: 1993 to 2002

The synthesis of eribulin mesylate from microgram to multi-gram scale is described in thisHighlight. Key coupling reactions include formation of the C30a to C1 carbon–carbon bond and macrocyclic ring closure through an intramolecular Nozaki–Hiyama–Kishi reaction.

The synthesis of the C27–C35 tetrahydrofuran fragment.

The synthesis of the C14–C21 aldehyde subfragment.

CLIP

In 1986, two Japanese chemists Hirata and Uemura [Y. Hirata, D. Uemura, Pure Appl. Chem. 58 (1986) 701.] isolated a naturally-occurring compound from the marine sponge Halichondria okadai (picture above, right). The compound was named Halichondrin B, and it immediately began to generate great excitement when it was realised that it was extremely potent at killing certain types of cancer cells in small-scale tests. As a result of this discovery, it was immediately given top priority to be tested against a wide range of other cancers, and became one of the first compounds to be evaluated using the novel 60-cell line method developed by the US National Cancer Institute (NCI). In this technique, 60 different types of human tumor cells (including leukemia, melanoma and cancers of the lung, colon, brain, ovary, breast, prostate, and kidney) are tested with the potential anti-cancer molecule delivered at a single dose of 10 μM concentration. This process can be run in parallel, with dozens of different molecules being tested against all 60 cancer cell lines at the same time in a huge array. Any molecules which exhibit significant growth inhibition are prioritised, and the test repeated on them, but this time at five different concentration levels.

Halichondrin B – the part of the molecule used to make Eribulin is shown in blue.

Unfortunately, the concentration of Halichondrin B in the sea sponge wasn’t enough to enable commercial production for use in chemotherapy. For example, a ton of sea sponges could only produce 300 mg of Halichondrin B! The race was on to try to synthesise Halichondrin B in the lab, which wasn’t easy due to its large size (molecular weight 1110) and complex structure. However, only 6 years later, chemists at Harvard University published the complete chemical synthesis of this molecule………..T.D. Aicher, K.R. Buszek, F.G. Fang, C.J. Forsyth, S.H. Jung, Y. Kishi, M.C. Matelich, P.M. Scola, D.M. Spero, S.K. Yoon, J. Am. Chem. Soc. 114 (1992) 3162

Although this was a great achievement, Halichondrin B was still far too complex and the sythesis route too expensive to do on a large scale. The molecule needed to be stripped down to its essential components, while keeping, or even improving, its anti-cancer efficacy. Many tests were performed, but eventually the work led to te development of the structurally-simplified and pharmaceutically-optimized analog, which was named Eribulin [3,4]. Eribulin mesylate was approved by the U.S. Food and Drug Administration in 2010, to treat patients with metastatic breast cancer [5], and it is currently being marketed by Eisai Co. under the trade nameHalaven . It is also being investigated for use in a variety of other solid tumors, including lung cancer, prostate cancer and sarcoma .

ERIBULIN

M.J. Towle, K.A. Salvato, J. Budrow, B.F. Wels, G. Kuznetsov, K.K. Aalfs, S. Welsh, W. Zheng, B.M. Seletsk, M.H. Palme, G.J. Habgood, L.A. Singer, L.V. Dipietro, Y. Wang, J.J. Chen, D.A. Quincy, A. Davis, K. Yoshimatsu, Y. Kishi, M.J. Yu, B.A. Littlefield, Cancer Res. 61 (2001) 1013.

M.J. Yu, Y. Kishi, B.A. Littlefield, in D.J. Newman, D.G.I. Kingston, G.M. Cragg, Anticancer agents from natural products, Washington, DC, Taylor and Francis (2005).

http://healthmad.com/conditions-and-diseases/breast-cancer-cure-from-the-sea/

http://www.clinicaltrials.gov/ct2/results?term=eribulin+OR+E7389

M.A. Jordan, L. Wilson, Nature Revs: Cancer 4 (2004) 253.

ERIBULIN

Patent Data

Exclusivity Data

The substance inhibits the polymerization of tubulin into microtubules and encapsulates tubulin molecules in non-productive aggregates from. The lack of training of the spindle apparatus blocks the mitosis and ultimately induces apoptosis of the cell. Eribulin differs from known microtubule inhibitors such as taxanes and vinca alkaloids by the binding site on microtubules, also it does not affect the shortening. This explains the effectiveness of the new cytostatic agent in taxane-resistant tumor cell lines with specific tubulin mutations.

Structure and mechanism

Structurally, eribulin is a fully synthetic macrocyclic ketone analogue of the marine sponge natural product halichondrin B,^[4][5] the latter being a potent naturally-occurring mitotic inhibitor with a unique mechanism of action found in the Halichondria genus of sponges.^[6][7] Eribulin is a mechanistically-unique inhibitor of microtubule dynamics,^[8][9] binding predominantly to a small number of high affinity sites at the plus ends of existing microtubules.^[10] Eribulin exerts its anticancer effects by triggering apoptosis of cancer cells following prolonged and irreversible mitotic blockade.^[11][12]

A new synthetic route to E7389 was published in 2009.^[13]

clip

Eisai R&D Management Co., Ltd.

13/9/2013

Halaven is a novel anticancer agent discovered and developed in-house by Eisai and is currently approved in more than 50 countries, including Japan, the United States and in Europe. In Russia, Halaven was approved in July 2012 for the treatment of locally advanced or metastatic breast cancer previously treated with at least two chemotherapy regimens including an anthracycline and a taxane. Approximately 50,000 women in Russia are newly diagnosed with breast cancer each year, with this type of cancer being the leading cause of death in women aged 45 to 55 years. read all at…………………….

http://www.dddmag.com/news/2013/09/eisai-launches-halaven-cancer-drug-russia

Eribulin mesylate (Halaven; Eisai) — a synthetic analogue of the marine natural product halichondrin B that interferes with microtubule dynamics — was approved in November 2010 by the US Food and Drug Administration for the treatment of metastatic breast cancer.

Family members of the product patent, WO9965894, have SPC protection in the EU until 2024 and one of its Orange Book listed filings, US8097648, has US154 extension till January 2021.

The drug also has NCE exclusivity till November 2015.

HALAVEN (eribulin mesylate) Injection is a non-taxane microtubule dynamics inhibitor. Eribulin mesylate is a synthetic analogue of halichondrin B, a product isolated from the marine sponge Halichondria okadai. The chemical name for eribulin mesylate is 11,15:18,21:24,28-Triepoxy-7,9-ethano12,15-methano-9H,15H-furo[3,2-i]furo[2′,3′:5,6]pyrano[4,3-b][1,4]dioxacyclopentacosin-5(4H)-one, 2[(2S)-3-amino-2-hydroxypropyl]hexacosahydro-3-methoxy-26-methyl-20,27-bis(methylene)-, (2R,3R,3aS,7R,8aS,9S,10aR,11S,12R,13aR,13bS,15S,18S,21S,24S,26R,28R,29aS)-, methanesulfonate (salt).

It has a molecular weight of 826.0 (729.9 for free base). The empirical formula is C₄₀H₅₉NO₁₁ •CH₄O₃S. Eribulin mesylate has the following structural formula:

HALAVEN is a clear, colorless, sterile solution for intravenous administration. Each vial contains 1 mg of eribulin mesylate as a 0.5 mg/mL solution in ethanol: water (5:95).

complete syn is available here

http://www.sciencedirect.com/science/article/pii/S0968089611010674

http://www.drugdevelopment-technology.com/projects/halaven-cancer/halaven-cancer1.html

Nitrogen: dark blue, oxygen: red, hydrogen: light blue graphics: Wurglics, Frankfurt am Main

clip

Macrocyclization process for preparing a macrocyclic intermediate of halichondrin B analogs, in particular eribulin, from a non-macrocyclic compound, using a carbon-carbon bond-forming reaction.

http://www.pnas.org/content/108/17/6699/F1.expansion.html

http://www.nature.com/nrd/journal/v8/n1/fig_tab/nrd2487_F6.html

UPDATED

WO 2015066729

Eisai has developed and launched eribulin mesylate for treating breast cancer.  Follows on from WO2014208774, claiming use of a combination comprising eribulin mesylate and lenvatinib mesylate, for treating cancer.

Macrocyclization reactions and intermediates useful in the synthesis of analogs of halichondrin B

The invention provides methods for the synthesis of eribulin or a pharmaceutically acceptable salt thereof (e.g., eribulin mesylate) through a macrocyclization strategy.  The macrocyclization strategy of the present invention involves subjecting a non-macrocyclic intermediate to a carbon-carbon bond-forming reaction (e.g., an olefination reaction (e.g., Horner-Wadsworth-Emmons olefination), Dieckmann reaction, catalytic Ring-Closing Olefin Metathesis, or Nozaki-Hiyama-Kishi reaction) to afford a macrocyclic intermediate.  The invention also provides compds. useful as intermediates in the synthesis of eribulin or a pharmaceutically acceptable salt thereof and methods for prepg. the same.

CLIPS

http://www.chemistry-blog.com/2012/09/15/from-natural-product-to-pharmaceutical/

In a recent discussion (Nicolau), about the suggested move of Prof. NicoIau from Scripps, the issue of the practicality of natural product total synthesis was raised. Here is a wonderful example of just that very usefulness, a wonderful piece of science extending over many years. It concerns the journey from Halichondrin B to Eribulin (E7389) a novel anti-cancer drug. The two compounds have the following structures:

I think you can see the relationship and as a development chemist I am glad they managed to simplify things (a bit).

Both compounds have an enormous number of possible isomers: Halichondrin B, with 32 stereocenters has 2³²possible isomers; Eribulin has 19 with 2¹⁹ isomers (if I have counted correctly, it does not really matter, there are lots of isomers). Remarkable is the fact that only one of these isomers is active in the given area of anti-cancer agents.

An excellent review of the biology and chemistry of these compounds has been published by Phillips etal¹. This review is an excellent read and is to be commended. Another one written by Kishi², is also full of information about the discovery of E7389 and I hope you will all get a chance to read this chapter.

The history of Halichondrin B goes back to 1987 when Blunt^2-5 isolated it with other similar compounds from extraction of 200Kg of a sponge. Independently Pettit isolated the same compound from a different species⁴. The appearance of this compound in different species of sponge may indicate that it is produced by a symbiote.

The biological activity of Halichondrin B is amazing. When evaluated against B-16 melanoma cells it was found to have an IC₅₀ of 0.093ng/mL. Against various cancers, generated in mice, it was shown to be affective at a daily dose of 5ug/kg, which resulted in a doubling of the survival rate. It has also been demonstrated that Halichondrin acts as a microtubule destabiliser and mitoitic spindle poison. It was proven that it is has tremendous in vivo activity against a variety of drug resistant cancers, lung, colon, breast, ovarian to mention a few. Consequently the National Cancer Institute selected it for pre-clinical trials and it’s here that the problems began. According to reference 1 the entire clinical development would require some 10g, and if successful the annual production amount would be between 1-5 kg. Blunt and co-workers managed to isolate 310mg from 1000kg-harvested sponge therefore, the only way to obtain the amounts required is total chemical synthesis. But synthesising 1-5 kg of such a compound would indeed be a mammoth task.

Kishi synthesised this compound⁷ in 1992 starting from carbohydrate precursors employing the Nozaki-Hiyama-Kishi Ni/Cr reaction, several times, in the long synthetic sequence^{8, 9}. Now as an aside I have used this reaction on scale several times and although it works well its success is very dependant upon the quality of the chromium source and also the presence of other trace transition metals.

In collaboration with Eisai work on the SAR of Halichondrin began. They had a good start: Thanks to the total syntheses of Kishi several advanced intermediates were available for biological screening and one popped out of the screen as being very active:

The first active lead compound

As one can see the complete left hand side of Halichondrin has gone! However, this compound was not active in vivo. Many derivatives and analogues of this compound were prepared: furans, diols, ketones and so on and a lead emerged from this complex SAR study, ER-076349. The vicinal diol was used as a handle for further refinement and lead ultimately to E7389, the clinical candidate.

It can be synthesised in around 35 steps from simple starting materials.

Going through all this work in a few sentences really belittles the tremendous amount of effort that went into discovery and development of this compound and the people involved are to be applauded for their dedication.

Kishi continues to optimise the synthesis of Eribulin as judged by a recent publication¹⁰. Where he describes an approach to the amino-alcohol-tetrahydrofuran part of Eribulin (top left fragment, compound 1 below). The retro-synthetic analysis is shown below. The numbering corresponds to that of Eribulin.

The first generation synthesis consisted of 20 steps and delivered compound 1 about 5% yield, the second-generation route was completed in 12 steps with a yield of 48%. One of the highlights includes a remarkable asymmetric hydrogenation¹¹ with Crabtree’s catalyst¹²:

This selectivity was not just luck; it seems to quite general, at least in this system. I always wonder how long it took them to stumble across this catalyst, but then I suppose that Eisai like most of the large pharma. companies has a hydrogenation group that probably indulges in catalyst screening.

The C34-C35 diol was obtained by a Sharpless asymmetric hydroxylation, here the diastereoisomeric ratio was not very high, only about 3:1 in favour of the desired isomer. Fortunately the undesired isomer could be removedcompletely by crystallisation.

This is a remarkable story and references 1 and 2 are worth reading to obtain the complete picture and learn lots of new chemistry as well. Eisai filed a NDA and the FDA approved the compound in 2010 for the treatment of metastatic breast cancer.

Patent

https://www.google.com/patents/WO2013142999A1?cl=en

EXAM PLE 23 : Preparation of Eribulin :

[00120] Compound E-12A (133 mg, 160 μηιοΙ, 1.0 eq) was dissolved in anhydrous dichloromethane (20 mL) and cooled to 0 °C. To this solution was sequentially added 2,6-lutidine (0.09 m L, 0.8 mmol, 5.0 eq), and trimethyl silyl triflate (TMSOTf) (0.12 m L, 0.64 mmol, 4.0 eq) and the cooling bath was removed . The reaction was stirred at room temperature for 1.5 hours and another portion of 2,6-lutidine (5.0 eq) and TMSOTf (4.0 eq) were added at room temperature. The reaction was further stirred for 1 hour and quenched with water (10 m L). The layers were separated and the organic phase was washed with additional water (2x 10 m L), brine (10 m L), dried over MgS0₄ and concentrated under reduced pressure. The residue was dissolved in MeOH (10 m L), a catalytic amount of K₂C0₃ was added at room temperature and the resulting mixture was stirred for 2 hours. The reaction was diluted with dichloromethane and quenched with water (10 mL). The layers were separated and the aqueous phase was further extracted with dichloromethane (5 x 10 m L). The combined organic layers were washed with brine (20 m L), dried over MgS0₄, filtered and concentrated. The residue was dissolved in dichloromethane and purified by column chromatography on silica gel, using 1 : 9 MeOH : CH₂CI₂ to 1 : 9 : 90 N H₄OH : MeOH : CH₂CI₂ as eluent. The product was afforded as a white amorphous solid (103 mg, 88%) . [00121] EXAMPLE 23 : Preparation of compound of formula 4a

D-Gulonolactone 4a

[00122] The compound of formula 4a was prepared from D-Gulonolactone according to the conditions described in PCT publication number WO 2005/118565. [00123] EXAMPLE 24: Preparation of Eribulin mesylate (3)

[00124] Eribulin mesylate (3) was prepared from Eribulin according to the conditions described in US patent application publication number US

2011/0184190.

PATENT

https://www.google.com/patents/EP2528914A1?cl=en

Halichondrin B analogs, e.g., eribulin or pharmaceutically acceptable salts thereof, can be synthesized from the C14-C35 fragment as described in U.S. Patent No. 6,214,865 and International Publication No. WO 2005/118565. In one example described in these references, the C14-C35 portion, e.g., ER- 804028, of the molecule is coupled to the C1-C13 portion, e.g., ER-803896, to produce ER-804029, and additional reactions are carried out to produce eribulin (Scheme 1):

Scheme 1

eribulin, eribulin mesylate

Scheme 2

ER-804028

Compound AE (280 mg, 0.281 mmol, 1 eq) was dissolved in CH₂C1₂ and cooled to 0 °C. Pyridine (0.045 ml, 0.56 mmol, 2.0 eq) was added followed by Ms₂0 (58.8 mg, 0.338 mmol, 1.20 eq). The reaction was allowed to warm to room temperature, and stirring was continued for an additional 1 h. The reaction mixture was cooled to 0 °C, diluted with MTBE (5.6 ml), washed with saturated NaHC0₃ (0.84 g), and concentrated to give crude product as colorless film. The crude was azeotropically dried with heptane (3 ml ^χ 2) and re-dissolved in THF (7.0 ml). The mixture was cooled to 0 °C and treated with 25 wt% NaOMe (0.13 ml). After 10 min, the reaction was allowed to warm to room temperature, and stirring was continued for an additional 30 min. The mixture was treated with additional 25 wt% NaOMe (0.045 ml), and stirring was continued for an additional 20 min. The reaction mixture was diluted with heptane (7.0 ml) and washed with water (1.4 ml). The organic layer was separated, sequentially washed with: 1) 20 wt% NH₄C1 (0.84 g) and 2) 20 wt% NaCl (3 g), and concentrated to give crude product as brownish oil. The crude was purified by Biotage (Uppsala, Sweden) 12M (heptane-MTBE 2:3 v/v) to give ER-804028 (209 mg, 0.245 mmol, 87%) as pale yellow oil. 1H NMR (400 MHz, CDC1₃): δ 7.89 (2H, m), 7.64 (IH, m), 7.56 (2H, m), 4.85 (IH, d, J= 1.6 Hz), 4.80 (IH, s), 4.72 (IH, s), 4.61 (IH, d, J= 1.6 Hz), 4.23 (IH, br), 3.91 (IH, m), 3.79 (IH, m), 3.76 (2H, m), 3.63 (IH, m), 3.50-3.60 (4H, m), 3.43 (IH, dd, J= 5.6 Hz, 10.0 Hz), 3.38 (3H, s), 3.32 (IH, m), 2.98 (2H, m), 2.61 (IH, br), 2.56 (IH, m), 2.50 (IH, m), 2.08-2.22 (3H, m), 1.96 (IH, m), 1.84 (IH, m), 1.78 (IH, m), 1.70 (IH, m), 1.42-1.63 (6H, m), 1.28-1.42 (2H, m), 1.01 (3H, d, J= 6.8 Hz), 0.84 (18H, s), 0.05 (3H, s), 0.04 (3H, s), 0.00 (3H, s), -0.01 (3H, s); and ¹³C NMR (100 MHz, CDC1₃): δ 150.34, 150.75, 139.91, 134.18, 129.73 (2C), 128.14 (2C), 105.10, 85.97, 80.92, 79.72, 78.50, 77.45, 77.09, 75.53, 71.59, 68.04, 62.88, 58.27, 57.73, 43.51, 42.82, 39.16, 37.68, 35.69, 33.31, 32.41, 31.89, 31.48, 29.79, 26.21 (3C), 26.17 (3C), 18.58, 18.38, 18.13, -3.85, – 4.71, -5.12 (2C).

CLIP

Eribulin mesylate (Halaven)
Eribulin is a highly potent cytotoxic agent approved in the US for the treatment of metastatic breast cancer for patients who have
received at least two previous chemotherapeutic regimens.30 Eribulin was discovered and developed by Eisai and it is currently
undergoing clinical evaluation for the treatment of sarcoma (PhIII) and non-small cell lung cancer which shows progression after platinum-based chemotherapy and for the treatment of prostate cancer (PhII). Early stage clinical trials are also underway to evaluate
eribulin’s efficacy against a number of additional cancers. Eribulin is a structural analog of the marine natural product halichondrin B.
Its mechanism of action involves the disruption of mitotic spindle formation and inhibition of tubulin polymerization which results
in the induction of cell cycle blockade in the G2/M phase and apoptosis.31 Several synthetic routes for the preparation of eribulin have
been disclosed,32–35 each of which utilizes the same strategy described by Kishi and co-workers for the total synthesis of halichondrin B.36 Although the scales of these routes were not disclosed in all cases, this review attempts to highlight what appears to be the production-scale route based on patent literature.37,38 Nonetheless, the synthesis of eribulin represents a significant accomplishment in the field of total synthesis and brings a novel chemotherapeutic option to cancer patients.
The strategy to prepare eribulin mesylate (V) employs a convergent synthesis featuring the following: the late stage coupling of
sulfone 22 and aldehyde 23 followed by macrocyclization under Nozaki–Hiyami–Kishi coupling conditions, formation of a challenging
cyclic ketal, and installation of the primary amine (Scheme 5).Sulfone 22 was further simplified to aldehyde 24 and vinyl triflate 25 which were coupled through a Nozaki–Hiyami–Kishi reaction.

The schemes that follow will describe the preparation of fragments 23, 24 and 25 along with how the entire molecule was assembled.
The synthesis of the C1–C13 aldehyde fragment 23 is described in Scheme 6. L-Mannonic acid-lactone 26 was reacted with cyclohexanone in p-toluene sulfonic acid (p-TSA) to give the biscyclohexylidene ketal 27 in 84% yield. Lactone 27 was reduced with
diisobutylaluminum hydride (DIBAL-H) to give lactol 28 followed by condensation with the ylide generated from the reaction of
methoxymethylene triphenylphosphorane with potassium tertbutoxide to give a mixture of E and Z vinyl ethers 29 in 81% yield.
Dihydroxylation of the vinyl ether of 29 using catalytic osmium teteroxide and N-methylmorpholine-N-oxide (NMO) with concomitant cyclization produced diol 30 in 52% yield. Bis-acetonide 30 was then reacted with acetic anhydride in acetic acid in the presence of ZnCl2 which resulted in selective removal of the pendant ketal protecting group. These conditions also affected peracylation, giving rise to tetraacetate 31 in 84% yield. Condensation of 31 with methyl 3-(trimethylsilyl)pent-4-enoate in the presence of boron trifluoride etherate in acetonitrile provided alkene 32. Saponification conditions using Triton B(OH) removed the acetate protecting groups within 32 and presumably induced isomerization of the alkene into conjugation with the terminal ester, triggering an intramolecular Michael attack of the 2-hydroxyl group, ultimately resulting in the bicylic-bispyranyl diol methyl ester 33 as a crystalline solid in 38% yield over two steps. Oxidative cleavage of the vicinal diol of 33 with sodium periodate gave aldehyde 34 which was coupled to (2-bromovinyl)trimethylsilane under Nozaki–Hiyami–Kishi conditions to give an 8.3:1 mixture of allyl alcohols 35 in 65% yield over two steps. Hydrolysis of the cyclohexylidine ketal 35 with aqueous acetic acid followed by recrystallization gave diastereomerically pure triol 36 which was reacted with tert-butyldimethylsilyl triflate (TBSOTf) to afford the tris-TBS ether 37 in good yield. Vinyl silane 37 was treated with NIS and catalytic tert-butyldimethylsilyl chloride (TBSCl) to give vinyl iodide 38 in 90% yield.
Reduction of the ester with DIBAL-H produced the key C1–C14 fragment 23 in 93% yield.
The preparation of the tetra-substituted tetrahydrofuran intermediate 24 is described in Scheme 7. D-Glucurono-6,3-lactone
39 was reacted with acetone and sulfuric acid to give the corresponding acetonide and the 5-hydroxyl group was then removed by converting it to its corresponding chloride through reaction with sulfuryl chloride (SO2Cl2) followed by hydrogenolysis
to give lactone 40 in good overall yield. Reduction of the lactone 40 with DIBAL-H gave the corresponding lactol which was condensed
with (trimethylsilyl)methylmagnesium chloride to afford silane 41. Elimination of the silyl alcohol of 41 was accomplished
under Peterson conditions with potassium hexamethyldisilazide (KHMDS) to afford the corresponding terminal alkene in 94% yield.
The secondary alcohol of this intermediate was alkylated with benzyl bromide to afford ether 42 in 95% yield. Asymmetric dihydroxylation of the alkene of 42 under modified Sharpless conditions using potassium osmate (VI) dehydrate (K2OsO4), potassium
ferricyanide (K3Fe(CN)6) and the (DHQ)2AQN ligand produced the vicinal diol which was then reacted with benzoyl chloride,
N-methylmorpholine, and DMAP to give di-benzoate 43 in excellent yield as a 3:1 mixture of diastereomeric alcohols. Allyl trimethylsilane was added to the acetal of 43 using TiCl3(OiPr) as the Lewis acid to give 44 in 83% yield. Re-crystallization of 44 from
isopropanol and n-heptane afforded 44 in >99.5% de in 71% yield.
Oxidation of the secondary alcohol of 44 under the modified Swern conditions generated the corresponding ketone which was condensed with the lithium anion of methyl phenyl sulfone to give a mixture of E and Z vinyl sulfones 45. Debenzylation of 45 using iodotrimethylsilane (TMSI) followed by chelation-controlled reduction of the vinyl sulfone through reaction with NaBH(OAc)3, and
then basic hydrolysis of the benzoate esters using K2CO3 in MeOH resulted in triol 46 as a white crystalline solid in 57% yield over the
five steps after re-crystallization. The vicinal diol of 46 was protected as the corresponding acetonide through reaction with 2,2-
dimethoxypropane and sulfuric acid and this was followed by methyl iodide-mediated methylation of the remaining hydroxyl
group to give methyl ether 47. The protecting groups within acetonide 47 were then converted to the corresponding bis-tert-butyldimethylsilyl ether by first acidic removal of the acetonide with aqueous HCl and reaction with TBSCl in the presence of imidazole to give bis-TBS ether 48. Then, ozonolysis of the olefin of 48 followed by hydrogenolysis in the presence of Lindlar catalyst afforded the key aldehyde intermediate 24 in 68% yield over the previous five steps after re-crystallization from heptane.
Two routes to the C14–C26 fragment 25 will be described as both are potentially used to prepare clinical supplies of eribulin.
The first route features a convergent and relatively efficient synthesis of 25, however it is limited by the need to separate enantiomers
and mixture of diastereomers via chromatographic methods throughout the synthesis.37 The second route to 25 is a
much lengthier synthesis from a step-counting perspective; however it takes full advantage of the chiral pool of starting materials
and requires no chromatographic separations and all of the products were carried on as crude oils until they could be isolated as
crystalline solids.38 The first route to fragment 25 is described in Scheme 8 and was initiated by the hydration of 2,3-dihydrofuran (49) using an aqueous suspension of Amberlyst 15 to generate the intermediate tetrahydro-2-furanol (50) which was then immediately reacted with 2,3-dibromopropene in the presence of tin and catalytic HBr to afford diol 51 in 45% for the two steps.

The primary alcohol of 51 was selectively protected as its tert-butyldiphenylsilyl ether using TBDPSCl and imidazole and the racemate was then separated using simulated moving bed (SMB) chromatography to give enantiopure 52 in 45% yield over the two steps. The secondary alcohol of 52 was reacted with p-toluenesulfonyl chloride and DMAP to give tosylate 53 in 78% yield which was used as a coupling partner later in the synthesis of this fragment. The synthesis of the appropriate coupling partner was initiated by condensing diethylmalonate with (R)-2-(3-butenyl)oxirane (54), followed by decarboxylation to give lactone 55 in 71% yield for the two step process. Methylation of the lactone with LHMDS and MeI provided 56 in 68% yield as a 6:1 mixture of diastereomers. The lactone 56 was reacted with the aluminum amide generated by the reaction of AlMe3 and N,O-dimethylhydroxylamine to give the corresponding Weinreb amide which was protected as its tert-butyldimethylsilyl ether upon reaction with TBSCl and imidazole to give 57 in 91% yield over the two steps. Dihydroxylation of the olefin of 57 by reaction with OsO4 and NMO followed by oxidative cleavage with NaIO4 gave the desired coupling partner aldehyde 58 in 93% yield. Aldehyde 58 was coupled with vinyl bromide 53 using an asymmetric Nozaki–Hiyami– Kishi reaction using CrCl2, NiCl2, Et3N and chiral ligand 66 (described in Scheme 9 below). The reaction mixture was treated with ethylene diamine to remove the heavy metals and give the secondary alcohol 59. This alcohol was stirred with silica gel in isopropanol to affect intramolecular cyclization to give the tetrahydrofuran 60 in 48% yield over the three step process. The Weinreb amide of 60 was reacted with methyl magnesium chloride to generate the corresponding methyl ketone which was converted to vinyl triflate 61 upon reaction with KHMDS and Tf2NPh. De-silylation of the primary and secondary silyl ethers with methanolic HCl gave the corresponding diol in 85% yield over two steps and the resulting mixture of diastereomers was separated using preparative HPLC to provide the desired diastereomer in 56% yield. The primary alcohol was protected as its pivalate ester with the use of pivaloyl chloride, DMAP and collidine; the secondary alcohol was converted     to a mesylate upon treatment with methanesulfonyl chloride (MsCl) and Et3N to give the C15–C27 fragment 25 in high yield.
The preparations of the chiral ligand 66 used in the coupling reaction in Scheme 8 along with the chiral ligand 67 utilized later
in the synthesis are described in Scheme 9. 2-Amino-3-methylbenzoic acid (62) was reacted with triphosgene to give benzoxazine
dione 63 in 97% yield, which then was reacted with either D- or L-valinol in DMF followed by aqueous LiOH to give alcohols 64
and 65, respectively in 65–75% yield for the two steps. Reaction of alcohol 64 or 65 with MsCl in the presence of DMAP effected formation of the dihydrooxazole ring and mesylation of the aniline to give the corresponding (R)-ligand 66 derived from D-valinol or the (S)-ligand 67 derived from L-valinol, respectively in high yield.
An alternative route to intermediate 25 is described in Scheme  10 and although much lengthier than the route described in
Scheme 8, it avoids chromatographic purifications as all of the products are carried on crude until a crystalline intermediate
was isolated and purified by re-crystallization. Quinic acid (68) was reacted with cyclohexanone in sulfuric acid to generate a protected
bicyclic lactone in 73% yield and the resulting tertiary alcohol was protected as its trimethylsilyl ether 69. Reduction of the
lactone 69 was accomplished with DIBAL-H and the resulting lactol  was treated with acetic acid to remove the TMS group and the resulting compound was reacted with acetic anhydride, DMAP and Et3N to give bis-acetate 70 in 65% yield for the three steps after re-crystallization. Methyl 3-(trimethylsilyl)pent-4-enoate was coupled to the acetylated lactol 70 in the presence of boron trifluoride etherate and trifluoroacetic anhydride to give adduct 71 in 62% yield. The acetate of 71 was removed upon reaction with sodium methoxide in methanol and the resulting tertiary alcohol cyclized on to the isomerized enone alkene to give the fused pyran ring. Reduction of the methyl ester with lithium aluminum hydride provided pyranyl alcohol 72. Mesylation of the primary alcohol was followed by displacement with cyanide anion to give nitrile 73.

The nitrile was methylated upon reaction with KHMDS and MeI and the resulting product was purified by re-crystallization
to provide nitrile 74 in 66% over the previous five steps in a 34:1 diastereomeric ratio. Acid hydrolysis of the ketal of 74 liberated
the corresponding diol in 72% yield and this was reacted with 2-acetoxy-2-methylpropionyl bromide to give bromo acetate 75.
Elimination of the bromide was accomplished upon treatment with 1,8-diazabicycloundec-7-ene (DBU) to give alkene 76 in 63%
yield for two steps. Ozonolysis of the cyclohexene ring followed by reductive work-up with NaBH4 and basic hydrolysis of the acetate
produced a triol which upon reaction with NaIO4 underwent oxidative cleavage to give cyclic hemiacetal 77 in 75% yield over
the previous four steps. Wittig condensation with carbomethoxymethylene triphenylphosphorane gave the homologated unsaturated
ester 78. Catalytic hydrogenation of the alkene using PtO2 as the catalyst was followed by converting the primary alcohol to the
corresponding triflate prior to displacement with sodium iodide resulted in iodide 79 in 75% yield over four steps. The ester of 79
was reduced to the corresponding primary alcohol upon reaction with LiBH4 in 89% yield and the resulting iodoalcohol was treated
with Zn dust to affect reductive elimination of the iodide and decomposition of the pyran ring system to give the tetrahydrofuran
diol 80 in 90% yield. This diol was treated with methanolic HCl to affect an intramolecular Pinner reaction and this was followed
by protection of the primary alcohol as its tert-butyldiphenylsilyl ether to give lactone 81 The lactone was reacted with the
aluminum amide generated from AlMe3 and N,O-dimethylhydroxylamine and the resulting secondary alcohol was protected as
its tert-butyldimethylsilyl ether to give Weinreb amide 82 in 99% crude yield over four steps. Compound 82 is the diastereomerically
pure version of compound 60 and can be converted to compound 25 by the methods described in Scheme 8 absent the required
HPLC separation of diastereomers. With the three key fragments completed, the next step was to assemble them and complete the synthesis of eribulin. Aldehyde 24 was coupled to vinyl triflate 25 using an asymmetric Nozaki– Hiyami–Kishi reaction using CrCl2, NiCl2, Et3 N and chiral ligand 67 (Scheme 9) to give alcohol 83 (Scheme 11).

Formation of the THP ring was accomplished by reaction with KHMDS which allowed for displacement of the mesylate with the secondary alcohol and provided the THP containing product in 72% yield for the three steps. The pivalate ester group was removed with DIBAL-H to give the western fragment 22 in 92% yield.
The completion of the synthesis of eribulin is illustrated in Scheme 12. The lithium anion of sulfone 22 generated upon reaction
with nBuLi was coupled to aldehyde 23 to give diol 84 in 84% yield. Both of the alcohol functional groups of 84 were oxidized
using a Dess–Martin oxidation in 90% yield and the resulting sulfone was removed via a reductive cleavage upon reaction with
SmI2 to give keto-aldehyde 85 in 85% yield. Macrocyclization of 85 was accomplished via an asymmetric Nozaki–Hiyami–Kishi
reaction using CrCl2, NiCl2, Et3N and chiral ligand 67 to give alcohol 86 in 70% yield. Modified Swern oxidation of the alcohol provided the corresponding ketone in 91% yield and this was followed by removal of the five silyl ether protecting groups upon reaction with TBAF and subsequent cyclization to provide ketone 87. Compound 87 was treated with PPTS to provide the ‘caged’ cyclic ketal 88 in 79% over two steps. The vicinal diol of 88 was reacted with Ts2O in collidine to affect selective tosylation of the primary alcohol and this crude product was reacted with ammonium hydroxide to install the primary amine to give eribulin which was treated
with methanesulfonic acid in aqueous ammonium hydroxide to give eribulin mesylate (V) in 84% yield over the final three steps.

30. Zheng, W.; Seletsky, B. M.; Palme, M. H.; Lydon, P. J.; Singer, L. A.; Chase, C. E.;
Lemelin, C. A.; Shen, Y.; Davis, H.; Tremblay, L.; Towle, M. J.; Salvato, K. A.;
Wels, B. F.; Aalfs, K. K.; Kishi, Y.; Littlefield, B. A.; Yu, M. J. Bioorg. Med. Chem.
Lett. 2004, 14, 5551.
31. Wang, Y.; Serradell, N.; Bolós, J.; Rosa, E. Drugs Future 2007, 32, 681.
32. Chiba, H.; Tagami, K. J. Synth. Org. Chem. Jpn. 2011, 69, 600.
33. Choi, H.; Demeke, D.; Kang, F.-A.; Kishi, Y.; Nakajima, K.; Nowak, P.; Wan, Z.-
K.; Xie, C. Pure Appl. Chem. 2003, 75, 1.
34. Kishi, Y.; Fang, F.; Forsyth, C. J.; Scola, P. M.; Yoon, S. K. WO 9317690 A1, 1993.
35. Littlefield, B. A.; Palme, M.; Seletsky, B. M.; Towle, M. J.; Yu, M. J.; Zheng, W.
WO 9965894 A1, 1999.
36. Aicher, T. D.; Buszek, K. R.; Fang, F. G.; Forsyth, C. J.; Jung, S. H.; Kishi, Y.;
Matelich, M. C.; Scola, P. M.; Spero, D. M.; Yoon, S. K. J. Am. Chem. Soc. 1992,
114, 3162.
37. Austad, B.; Chase, C. E.; Fang, F. G. WO 2005118565 A1, 2005.
38. Chase, C.; Endo, A.; Fang, F. G.; Li, J. WO 2009046308 A1, 2009.

CLIP

http://www.rsc.org/chemistryworld/2015/06/longest-organic-syntheses-natural-product

Eribulin (Halaven)

Halichondrin B is a wicked molecule. In tests in mice, it is an extremely potent cancer cell killer, active at around 80 picomolar concentration. It also possesses a fiendish macrocyclic polyketide structure, with 32 stereocentres meaning that it could adopt over four billion different isomers – with just one that fights cancer.

Its power is therefore inherently hard to harness. Halichondrin B was found in various sea sponge species in the 1980s, but getting 400mg  of the compound from a tonne of sponge was doing well. Clinical development required at least 10g, and annual production takes kilograms.

Although developing a synthetic route to halichondrin B looked just as tough as trying to extract it from sponges, Yoshito Kishi’s group at Harvard University in the US accepted the challenge. Frank Fang, one of the team, recalls how the Nozaki–Hiyama–Kishi (NHK) coupling reaction would prove critical. ‘Another feature that was impressed upon me was the importance of crystalline intermediates,’ Fang adds. These allowed simple purification by recrystallisation, rather than expensive and time-consuming chromatography.

Published in 1992, their method used several NHK couplings, forming carbon–carbon bonds between multifunctional vinyl halides and aldehydes via a nickel-catalysed, chromium-mediated process.⁴ The sprawling convergent synthesis, whose longest linear sequence involved 47 steps, prompted Japanese pharmaceutical company Eisai to collaborate with Kishi in exploring halichondrin B’s structure–activity relationship. On screening the team’s intermediates, one featuring the macrocyclic half of halichondrin B proved especially active. A series of medicinal chemistry refinements led to what would eventually becomeeribulin (marketed by Eisai as Halaven), promising a slightly simpler synthesis. It has ‘just’ 19 stereocentres, which along with other structural restrictions cuts the possible number of isomers to a mere 16,384.

Fang joined Eisai in 1998 as it selected eribulin for further development, and worked to develop a production process for a route that produced it from three fragments. He again strove to exploit recrystallisation and use the NHK reaction, although making it reliable enough for manufacturing was challenging. ‘There was an appreciation for the somewhat sensitive nature of the reaction, particularly the asymmetric variant,’ he recalls.

The Eisai researchers therefore studied the NHK procedure as they applied it to redesigning the synthesis for part of the eribulin molecule they refer to as the C14–C26 fragment. Featuring just one ring, this fragment isn’t the most structurally complex of the three, but is still very difficult to make. That’s because it is a long chain with several stereocentres, whose stereochemistry is hard to link together.

Fang’s team initially broke this section down into two sub-fragments, C14–C19 and C20–C26, using asymmetric NHK reactions on each, learning about the reaction’s parameters as they did so.⁵ They then used what they’d found out to devise NHK reactions linking the two sub-fragments and attaching the two fragments on either side, which included closing the eribulin macrocycle. ‘We gained knowledge through our studies on the C19–C20 NHK coupling and were ultimately able to utilise that knowledge to try to execute an asymmetric NHK reaction in fixed equipment on multi-kilogram scale and construct the C19–C20, C26–C27, and C13–C14 bonds,’ Fang explains.

Halaven was approved in the US in 2010 to treat breast cancer and earned ¥2.89 billion in sales (£159 million) in 2014. The commercial route initially took 62 steps across a convergent synthesis bringing together three fragments, with a longest linear sequence of 30 steps. Fang’s team has since added seven steps to the C14–C26 fragment route, which counterintuitively cuts costs and waste by 80% by eliminating chromatography.⁶ ‘I am hopeful that we can find the lessons applicable in future work,’ Fang says.

Cheaper synthesis would appear welcome, given that Halaven’s price tag has been criticised. In the UK it currently costs £2,000 per 21 day treatment cycle according to data from the British National Formularyand the country’s National Institute for Health and Clinical Excellence (Nice). As a result, Nice refused to cover the drug, and in January 2015 the remaining funding in England looked set to be closed off with Halaven being taken off the Cancer Drugs Fund (CDF)’s list. But Eisai was told in March that the drug would stay on the list, pending reconsideration, after an appeal against the decision.

In defence, Fang claims that Halaven is actually one of the most affordable breast cancer treatments on the CDF. ‘Eisai was given no opportunity to lower the price of Halaven before NHS England announced that the treatment would be removed from the fund, despite this being something we were, and still are, very willing to do,’ he adds.

References

SEE          https://wordpress.com/post/newdrugapprovals.org/3955

Eribulin

Systematic (IUPAC) name
2-(3-Amino-2-hydroxypropyl)hexacosahydro-3-methoxy- 26-methyl-20,27-bis(methylene)11,15-18,21-24,28-triepoxy- 7,9-ethano-12,15-methano-9H,15H-furo(3,2-i)furo(2′,3′-5,6) pyrano(4,3-b)(1,4)dioxacyclopentacosin-5-(4H)-one
Clinical data
Trade names	Halaven
AHFS/Drugs.com	Consumer Drug Information
MedlinePlus	a611007
License data	US FDA: Eribulin
Pregnancy category	US: D (Evidence of risk)
Routes of administration	Intravenous
Legal status
Legal status	US: ℞-only
Identifiers
CAS Number	253128-41-5
ATC code	L01XX41 (WHO)
PubChem	CID 17755248
ChemSpider	21396142
UNII	LR24G6354G
ChEMBL	CHEMBL1237028
Chemical data
Formula	C40H59NO11
Molar mass	729.90 g/mol

////////Halaven, ERIBULIN, anticancer drug ,  Eisai Co.  E7389,  ER-086526,  US NCI designation,  NSC-707389.   breast cancer,  liposarcoma, halichrondrin B analog, B1939, E7389, ER-086526, 441045-17-6, FDA 2010, 253128-41-5 , ERIBULIN MESYLATE, Antineoplastic, エリブリンメシル酸塩

CC1CC2CCC3C(=C)CC(O3)CCC45CC6C(O4)C7C(O6)C(O5)C8C(O7)CCC(O8)CC(=O)CC9C(CC(C1=C)O2)OC(C9OC)CC(CN)O.CS(=O)(=O)O

C[C@@H]1C[C@@H]2CC[C@H]3C(=C)C[C@@H](O3)CC[C@]45C[C@@H]6[C@H](O4)[C@H]7[C@@H](O6)[C@@H](O5)[C@@H]8[C@@H](O7)CC[C@@H](O8)CC(=O)C[C@H]9[C@H](C[C@H](C1=C)O2)O[C@@H]([C@@H]9OC)C[C@@H](CN)O.CS(=O)(=O)O

C[C@@H]1C[C@@H]2CC[C@H]3C(=C)C[C@@H](O3)CC[C@]45C[C@@H]6[C@H](O4)[C@H]7[C@@H](O6)[C@@H](O5)[C@@H]8[C@@H](O7)CC[C@@H](O8)CC(=O)C[C@H]9[C@H](C[C@H](C1=C)O2)O[C@@H]([C@@H]9OC)C[C@@H](CN)O.CS(=O)(=O)O

CREDIT

http://www.chm.bris.ac.uk/motm/eribulin/eribulinh.htm

253128-41-5  CAS

Eribulin

Lovastatin (Merck’s Mevacor) is a statin drug, used for lowering cholesterol (hypolipidemic agent) in those withhypercholesterolemia to reduce risk of cardiovascular disease. Lovastatin is a naturally occurring compound found in food such asoyster mushrooms,^[2] red yeast rice,^[3] and Pu-erh.^[4]

Medical uses

The primary uses of lovastatin is for the treatment of dyslipidemia and the prevention of cardiovascular disease.^[5] It is recommended to be used only after other measures, such as diet, exercise, and weight reduction, have not improved cholesterol levels.^[5]

Structure

History

 Compactin and lovastatin, natural products with a powerful inhibitory effect on HMG-CoA reductase, were discovered in the 1970s, and taken into clinical development as potential drugs for lowering LDL cholesterol.

However, in 1980, trials with compactin were suspended for undisclosed reasons (rumoured to be related to serious animal toxicity). Because of the close structural similarity between compactin and lovastatin, clinical studies with lovastatin were also suspended, and additional animal safety studies initiated.

In 1982 some small-scale clinical investigations of lovastatin, a polyketide derived natural product isolated from Aspergillus terrus, in very high-risk patients were undertaken, in which dramatic reductions in LDL cholesterol were observed, with very few adverse effects. After the additional animal safety studies with lovastatin revealed no toxicity of the type thought to be associated with compactin, clinical studies resumed.

Large-scale trials confirmed the effectiveness of lovastatin. Observed tolerability continued to be excellent, and lovastatin was approved by the US FDA in 1987.

Lovastatin at its maximal recommended dose of 80 mg daily produced a mean reduction in LDL cholesterol of 40%, a far greater reduction than could be obtained with any of the treatments available at the time. Equally important, the drug produced very few adverse effects, was easy for patients to take, and so was rapidly accepted by prescribers and patients. The only important adverse effect is myopathy/rhabdomyolysis. This is rare and occurs with all HMG-CoA reductase inhibitors.

 Mechanism of action

Lovastatin is an inhibitor of 3-hydroxy-3methylglutaryl-coenzyme A reductase (HMG-CoA reductase), an enzyme which catalyzes the conversion of HMG-CoA to mevalonate. Mevalonate is a required building block for cholesterol biosynthesis and lovastatin interferes with its production by acting as a competitive inhibitor for HMG-CoA which binds to the HMG-CoA reductase. Lovastatin, being inactive in the native form, the form in which it is administered, is hydrolysed to the β-hydroxy acid form in the body and it is this form which is active. Presumably, the reductase acts on the hydrolyzed lovastatin to reduce the carboxylic acid moiety.

Discovery, Biochemistry and Biology

 It is now generally accepted that a major risk factor for the development of coronary heart disease is an elevated concentration of plasma cholesterol, especially lowdensity lipoprotein (LDL) cholesterol. The objective is to decrease excess levels of cholesterol to an amount consistent with maintainence of normal body function. Cholesterol is biosynthesized in a series of more than 25 separate enzymatic reactions that initially involves 3 successive condensations of acetyl-CoA units to form a 6-carbon compound, 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA). This is reduced to mevalonate and then converted in a series of reactions to the isoprenes that are building blocks of squalene, the immediate precursor to sterols, which cyclizes to lanosterol (a methylated sterol) and further metabolized to cholesterol. A number of early attempts to block the synthesis of cholesterol resulted in agents that inhibited late in the biosynthetic pathway between lanosterol and cholesterol. A major rate limiting step in the pathway is at the level of the microsomal enzyme which catalyzes the conversion of HMG CoA to mevalonic acd and which has been considered to be a prime target for pharmacologic intervention for several years.

            HMG CoA reductase occurs early in the biosynthetic pathway and is among the first commited steps to cholesterol formulation. Inhibition of this enzyme could lead to accumulation of HMG CoA, a water-soluble intermediate that is then capable of being readily metabolized that is then capable of being readily metabolized to simpler molecules. This inhibition of reductase would nto lead to accumulation of lipophylic intermediates having a formal sterol ring.

            Lovastatin is the first specific inhibitor of HMG CoA reductase to receive approval for the treatment of hypercholesterolemia. The first breakthrough in efforts to find a potent, specific, competitive inhibitor of HMG CoA reductase occurred in 1976 when Endo et al reported discovery of mevastatin, a highly functionalized fungal metabolite, isolated from cultures of  Penicillium citrium. Mevastatin was demonstrated to be an unusually potent inhibitor of the target enzyme and of cholesterol biosynthesis. Subsequent to the first reports describing mevastatin, efforts were initiated to search for other naturally occurring inhibitors oh HMG CoA reductase. This led to the discovery of a novel fungal metabolite – Lovastatin. The structure of Lovastatin was determined to be different from that of mevastatin by the presence of a 6 alphamethyl group in the hexahydronaphthalene ring.

Key points from the study of the Biosynthesis of Lovastatin :-

– Lovastatin is comprised of 2 polyketide chains derived from acetate that are 8- and 4-

  carbons long coupled in head to tail fashion.

– 6 alphamethyl group and the methyl group on the 4-carbon side chain are derived from

  the methyl group of methionine, and

– 6 alphamethyl group is added before closure of the rings.

This implies that lovastatin is a unique compound synthesized by A. terreus and that mevastatin is not an intermediate in its fornmation.

Cholesterol Biosynthetic Pathway

The HMG CoA reductase reaction

Biosynthesis — Diels-Alder Catalyzed Cyclization

            In vitro formation of a triketide lactone using a genetically-modified protein derived from 6-deoxyerythronolide B synthase has been demonstrated. The stereochemistry of the molecule supports the intriguing idea that an enzyme-catalyzed Diels-Alder reaction may occur during assembly of the polyketide chain. It thus appears that biological Diels-Alder reactions may be triggered by generation of reactive triene systems on an enzyme surface.

Biosynthesis – Using Broadly specific Acyltransferase

^{It has been found that a dedicated acyltransferase, LovD, is encoded in the lovastatin biosynthetic pathway. LovD has a broad substrate specificity towards the acyl carrier, the acyl substrate and the decalin acyl acceptor. It efficiently catalyzes the acyl transfer from coenzyme A thoesters or N-acetylcysteamine (SNAC) thioesters to monacolin J.}

            ^{The biosynthesis of Lovastatin is coordinated by two iterative type I polyketide synthases and numerous accessory enzymes. Nonketide, the intermediate biosynthetic precursor of Lovastatin, is assembeled by the upstream megasynthase LovB (also known as lovastatin nonaketide synthase), enoylreductase LovC, and CYP450 oxygenases. The five carbon unit side chain is synthesized by LovF (also known as lovastatin diketide synthase) through a single condensation diketide undergoes methylation and reductive tailoring by the individual LovF catalytic domains to yield an α-S-methylbutyryl thioester covalently attached to the phosphopantetheine arm on the acyl carrier protein (ACP) domain of LovF. Encoded in the gene cluster is a 46kDa protein, LovD, which was initially identified as an esterase homolog. LovD, which was initially identified as an esterase homolog. LovD was suggested to catalyze the last step of lovastatin biosynthesis that regioselectively transacylates the acyl group from LovF to the C8 hydroxyl group of the Nonaketide to yield Lovastatin.} 

K. Auclair, A. Sutherland, J. Kennedy, D. J. Witter, J. P. Van den Heever, C. R. Hutchinson and J. C. Vederas, Lovastatin Nonaketide Synthase Catalyses An Intramolecular Diels-Alder Reaction Of A Substrate Analogue, J. Am. Chem. Soc., 2000, 122, 11519-11520. DOI: 10.1021/ja003216+

http://pubs.rsc.org/en/content/articlelanding/2013/np/c2np20069d/unauth#!divAbstract

http://www.hindawi.com/journals/bmri/2012/196264/#B30

1. Z. Jia, X. Zhang, Y. Zhao, and X. Cao, “Enhancement of lovastatin production by supplementing polyketide antibiotics to the submerged culture of Aspergillus terreus,” Applied Biochemistry and Biotechnology, vol. 160, no. 7, pp. 2014–2025, 2010. 

Patent

https://www.google.com/patents/US6307066

PATENT

https://www.google.com/patents/WO2002009697A1?cl=en

https://www.google.com/patents/EP0625208B1?cl=en

Total Synthesis

^{A major bulk of work in the synthesis of Lovastatin was done by M. Hirama in the 1980’s. Hirama synthesized Compactin and used one of the intermediates to follow a different path to get to Lovastatin. The synthetic sequence is shown in the schemes below. The γ-lactone was synthesized using Yamada methodology starting with aspartic acid. Lactone opening was done using lithium methoxide in methanol and then silylation to give a separable mixture of the starting lactone and the silyl ether. The silyl ether on hydrogenolysis followed by Collins oxidation gave the aldehyde. Stereoselective preparation of (E,E)-diene was accomplished by addition of trans-crotyl phenyl sulfone anion, followed by quenching with Ac2O and subsequent reductive elimination of sulfone acetate. Condensation of this with Lithium anion of dimethyl methylphosphonate gave compound 1.Compound 2 was synthesized as shown in the scheme in the synthetic procedure. Compounds 1 and 2 were then combined together using 1.3eq sodium hydride in THF followed by reflux in chlorobenzene for 82 hrs under nitrogen to get the enone 3.}

^{Simple organic reactions were used to get to Lovastatin as shown in the scheme.}

Pharmacopoeia Information

^{Lovastatin tablets are preserved in well closed, light resistant containers. Protected from light and stored either in a cool place or at controlled room temperature.}

^{Lovastatin tablets are tested for Dissolution and Assay as per the USP.}

^{Limit for Dissolution – Not less than 80% (Q) of the labeled amount of Lovastatin is dissolved in 30 mins.}

^{Limit for Assay – Each tablet contains not less than 90% and not more than 110% of the labeled amount of Lovastatin, tested by HPLC analysis.}

^{Lovastatin raw material contains 5 impurities – A, B, C, D and E (as shown below).}

Market brands and other analogues  

^{There are other derivatives of Lovastatin which possess cholesterol reducing activity. Simvastatin (Zocor®) is another statin closely related to Lovastatin, differing only by the presence of a methyl group in the butanoyl ester moiety. Both effective in lowering total cholesterol.}

^{Another statin having vastly different structure but a popular drug – Atorvastatin (Lipitor®), administered as a calcium salt is a pyrrole derivative and a synthetic compound rather than a natural product.}

NMR

  ^{1 H NMR spectrum of lovastatin, 300 MHz, solvent CDCl 3 .} 

UV LOVASTATIN

Figure 6. The mean FT-IR spectra (the calibration set) and variables selected after application of UVE-PLS for modelling lovastatin (triangles) and wavenumbers for characteristic peaks for lovastatin IR spectrum (dots).

PATENT

https://www.google.com/patents/EP0702679B1?cl=en

Lovastatin is produced as a secondary metabolite of the fungusAspergillus terreus (US 4,231,938) deposited in American Type Culture Collection under Nos. ATCC 20541, ATCC 20542, and Monascus ruberdeposited in Fermentation Research Institute Agency of Industrial Science and Technology, Ministry of International Trade and Industry, Japan (DE 30 06 216 A1) under No. Ferm 4822. Other kinds of microorganisms producing lovastatin are known as well, e.g. a mutant of the microorganism Aspergillus terreus andAspergillus oryzae marked ATCC 74135.

Lovastatin is chemically 1′,2′,6′,7′,8a’-hexahydro-3,5-dihydroxy-2′,6′-dimethyl-8′-2″-methyl-1″-oxobutoxy)-1-naphtalene heptanoic acid-5-lactone (Stubbs et al., 1986) of the formula (EP 0 033 537 A1)

An active form of lovastatin is also an acid, which is chemically 1,2,6,8,8a-hexahydro-β,δ-dihydroxy-1-naphtalene heptanoic acid (Alberts et al., 1980) of the formula (EP 0 022 478 A1)

The lactone form of lovastatin is used as an agent for reducing cholesterol level in blood (Scott M.G. and Vega G.L, 1985). It inhibits the biosynthesis of mevalonic acid by inhibition of 3-hydroxy-3-methylglutaryl A reductase coenzyme (HMG-CoA reductase, E.C. 1.1.1.34) (Zubay et al., 1984).

Prior Art

After the completed fermentation, lovastatin is present in the broth in the lactone form (compound I) and in the acid form (compound II). In the isolation process as disclosed in EP 0 033 536 A2, lovastatin is extracted from the broth with ethyl acetate. The extract is concentrated by vacuum distillation. Since lovastatin is present in the lactone form as well as in the acid form and only the lactone is of commercial interest, the acid form should be converted into the lactone. The lactonisation is carried out by the reflux of the concentrate in toluene at 106 °C for 2 hours. After the lactonisation is complete, the solution is concentrated to a small volume. A pure substance is obtained by means of purifying the concentrate on columns packed with silica gel, in the presence of solvents such as ethyl acetate or n-hexane. The collected fractions are again concentrated in vacuo and then pure lovastatin crystallizes in the lactone form.

Due to the sophisticated multi-step procedure and vigorous conditions applied during the isolation, the yields of lovastatin are generally low. Different solvents, which in part exhibit toxicity, are used such as benzene, toluene, acetonitrile or ethyl acetate. Hence working with these solvents endangers the health of the persons involved and poses a problem with respect to the environment.

https://www.google.com/patents/EP0702679B1?cl=en

The structure was confirmed by IR spectroscopy (Fig.1), mass spectroscopy (Fig. 2), NMR (Fig. 3) and UV spectroscopy (Fig. 4).

IR spectrum of lovastatin.

References

Lovastatin

Systematic (IUPAC) name
(1S,3R,7S,8S,8aR)-8-{2-[(2R,4R)-4-Hydroxy-6-oxooxan-2-yl]ethyl}-3,7-dimethyl-1,2,3,7,8,8a-hexahydronaphthalen-1-yl (2S)-2-methylbutanoate
Clinical data
Trade names	Mevacor
AHFS/Drugs.com	Monograph
MedlinePlus	a688006
Pregnancy category	US: X (Contraindicated)
Routes of administration	Oral
Legal status
Legal status	US: ℞-only
Pharmacokinetic data
Bioavailability	<5%[1]
Protein binding	>98%[1]
Metabolism	Hepatic (CYP3A andCYP2C8 substrate)[1]
Biological half-life	2–5 hours[1]
Excretion	Faeces (83%), urine (10%)[1]
Identifiers
CAS Number	75330-75-5
ATC code	C10AA02 (WHO)
PubChem	CID 53232
IUPHAR/BPS	2739
DrugBank	DB00227
ChemSpider	48085
UNII	9LHU78OQFD
KEGG	D00359
ChEBI	CHEBI:40303
ChEMBL	CHEMBL503
Synonyms	Monacolin K, Mevinolin
Chemical data
Formula	C24H36O5
Molar mass	404.54 g/mol

^{////////////////}

Figure 1. Production of artemisinic acid or β-farnesene by engineered yeast. The sesquiterpene alkenes β-farnesene and amorphadiene are both derived from FPP (farnesyl diphosphate) by the action of specific enzymes introduced from plants: amorphadiene synthase (ADS) generates amorphadiene and β-farnesene synthase (FS) generates β-farnesene. Production strains express either ADS or FS, not both. Oxidation of amorphadiene to artemisinic acid is accomplished by the action of five plant enzymes expressed in the engineered yeast.17 Conversion of purified artemisinic acid to artemisinin is accomplished by in vitro organic chemistry. Isoprenoid production strains make little ethanol.

The antimalarial drug artemisinin and the specialty chemical β-farnesene are examples of natural product isoprenoids that can help solve global challenges, but whose usage has previously been limited by supply and cost impediments. This review describes the path to commercial production of these compounds utilizing fermentation of engineered yeast. Development of commercially viable yeast strains was a substantial challenge that was addressed by creation and implementation of an industrial synthetic biology pipeline. Using the engineered strains, production of β-farnesene from Brazilian sugarcane offers several environmental advantages. Among the many commercial applications of β-farnesene, its use as a feedstock for making biodegradable lubricants is highlighted. This example, along with others, highlight a powerful new suite of technologies that will become increasingly important for production of chemicals, spanning from pharmaceuticals through commodity chemicals.

Figure 2. Sanofi industrial semi-synthesis of artemisinin. The process starts with a moderate pressure catalytic diastereoselective hydrogenation of artemisinic acid to produce a high (95:5) ratio of the desired (R)-isomer. To avoid formation of a lactone byproduct, dihydro-epi-deoxyarteannuin B, during the photooxidation, the carboxylic acid is protected as a mixed anhydride. The final step combines formation of the intermediate hydroperoxide via photoxidation using a Hg vapor lamp and commercially available tetraphenylporphyin (TPP) as sensitizer with a Hock cleavage and rearrangement catalyzed by trifluoroacetic acid to give, after workup, the best yield reported to date of pure isolated artemisinin (55%).

Synthetic Biology and the Development of Commercial β-Farnesene Production Strains Semi-synthetic artemisinin is a pharmaceutical with a price point comparable to plant-derived artemisinin,20 namely above $150 per kg. β-Farnesene, however, is a specialty chemical with multiple uses (more details below); most specialty and commodity chemicals have significantly lower price points, often below $10 per kg. For these product categories, it is of paramount importance that fermentative production be as efficient as possible, with high yields (namely, grams of product made per gram of feed substrate), productivities (grams of product/liter of culture/hour) and concentration (also known as titer; grams of product per liter of culture). Developing yeast strains capable of the yield, productivity and titer required for chemical production requires extensive development, and has been enabled over the last decade by the new discipline of synthetic biology. Synthetic biology seeks to extend approaches and concepts from engineering and computation to redesign biology for a chosen function;21recent advances in the application of design automation, i.e., the use of software, hardware and robotics22 have enabled the creation and screening of hundreds of thousands of strain variants (created by both design and random mutagenesis) for the properties required for commercial production of β-farnesene. Notable enabling technologies developed for routine usage include rapid and reliable assembly of large (i.e., multiple kilobase) deoxyribonucleic acid (DNA) constructs;23-25 high throughput, cost effective, verification of structural DNA assemblies by both initial restriction digest26 and by low-cost DNA sequencing;27 and whole genome sequencing of yeast strains.28 In addition, there is a need to effectively identify the best new strains (akin to panning for gold!) through high throughput, rapid, and accurate methods to screen thousands of strains. Further, the results of small-scale (< 1 milliliter) tests must correspond to the results of large-scale (> 50,000 liter) production. Development and implementation of these technologies required considerable investment by Amyris. The outcome is a robust pipeline for efficient, cost-effective strain generation allied with screening for the properties required for commercial production of β-farnesene by fermentation (i.e., at a price point required for its use as a specialty chemical).

As the world’s population and economies grow, the demand for a wide variety of specialty, commodity, and pharmaceutical chemicals will outpace the supply available from current sources. There is an urgent need to develop alternative, sustainable sources of many existing chemicals and to develop abundant sources of currently scarce chemicals with novel beneficial properties. Synthetic biology and industrial fermentation, combined with synthetic chemistry, will be an increasingly important source of chemicals in the decades ahead; artemisinin and β-farnesene provide good examples of this relatively new approach to chemical production. Brazil’s plentiful sugar cane feedstock and fermentation expertise make it an excellent location for this type of manufacturing, which can expand and diversify the nation’s industrial base and international importance.

J. Braz. Chem. Soc. 2016, 27(8), 1339-1345

Developing Commercial Production of Semi-Synthetic Artemisinin, and of β-Farnesene, an Isoprenoid Produced by Fermentation of Brazilian Sugar

Kirsten R. Benjamin; Iris R. Silva; João P. Cherubim; Derek McPhee; Chris J. Paddon

How to cite this article

Genes encoding the biosynthetic pathway for production of a valuable product (e.g., farnesene) in a native organism are expressed in a heterologous microbial host (e.g., yeast). The engineered yeast produces farnesene by commercial fermentation. Copyright © 2016 Amyris, inc. All rights reserved.

http://dx.doi.org/10.5935/0103-5053.20160119

http://jbcs.sbq.org.br/imagebank/pdf/v27n8a04.pdf

Benjamin KR, Silva IR, Cherubim JP, Mcphee D, Paddon CJ. Developing Commercial Production of Semi-Synthetic Artemisinin, and of β-Farnesene, an Isoprenoid Produced by Fermentation of Brazilian Sugar. J. Braz. Chem. Soc. 2016;27(8):1339-1345

Kirsten R. Benjamin,a Iris R. Silva,b João P. Cherubim,c Derek McPheea and Chris J. Paddon*,a a Amyris, Inc., 5885 Hollis Street, Suite 100, CA 94608 Emeryville, USA b Amyris Brasil Ltda, Rua John Dalton 301-Bloco B-Edificio 3, Condominio Techno Plaza, 13069-330 Campinas-SP, Brazil c Amyris Brasil Ltda, Rodovia Brotas/Torrinha-km 7.5, 17380-000 Brotas-SP, Brazil

*e-mail: paddon@amyris.com

Chris Paddon, PhD

Dr. Paddon has a PhD in Biochemistry from Imperial College, London, but now considers himself a synthetic biologist. After postdoctoral work at the National Institutes of Health in Bethesda, MD, he worked in the pharmaceutical industry (GlaxoSmithKline), and then for two Bay Area biopharmaceutical companies (Affymax and Xenoport) before joining Amyris, Inc. in 2005 as its sixth employee and first scientist. He was project leader for the semi-synthetic artemisinin project at Amyris, Inc. and has subsequently led a number of other projects and programs there.

Chris Paddon is a Principal Scientist at Amyris, Inc. in Emeryville, CA. He was project leader for the Semi-Synthetic Artemisinin project, and subsequently led a number of projects at Amyris using synthetic biology for the production of natural products. He received his Bachelor’s degree in Microbiology from The University of Surrey (UK), and doctorate in Biochemistry from Imperial College (London, UK). Following postdoctoral work at The National Institutes for Health (Bethesda, MD) he joined the pharmaceutical industry, working for GSK (London, UK). He subsequently worked for Affymax (Palo Alto, CA) and Xenoport (Santa Clara, CA) before joining Amyris.

//////////// Commercial Production, Semi-Synthetic , Artemisinin,  farnesene, fermentation, natural product, lubricant

If you have difficulty in viewing click,,,,,,,,,,http://www.allfordrugs.com/2016/08/07/pharmaceutical-manufacturing-encyclopedia-3rd-edition/

DESCRIPTION

//////////

Nacubactam

RG-6080,  FPI-1459,  OP-0595, WK ?, WK-?, WK?

(2S,5R)-N-(2-amino ethoxy)-6-(sulfooxy)-7-oxo-1,6-diazabicyclo[3.2.1]octane-2-carboxamide

Beta lactamase inhibitor

Roche, under license from Meiji Seika Pharma and Fedora Pharmaceuticals is developing nacubactam hydrate

Meiji Seika Pharma Co., Ltd., Ｍｅｉｊｉ Ｓｅｉｋａファルマ株式会社

A diazabicyclooctane beta-lactamase inhibitor, for treating bacterial infection. In July 2016, nacubactam was reported to be in phase 1 clinical development

PATENTS , IN2015MU287, WO2016116878, WO 2016120752, INDICATE INTEREST FROM WOCKHARDT

• Originator Fedora Pharmaceuticals
• Developer Meiji Seika Pharma
• Class Antibacterials; Azabicyclo compounds
• Mechanism of Action Beta lactamase inhibitors

• Phase I Bacterial infections

Most Recent Events

• 13 Jan 2015  OP 0595 licensed to Roche worldwide, except Japan ,
• 30 Nov 2014 Meiji Seika Pharma completes a phase I trial in Healthy volunteers in Australia (NCT02134834)
• 01 May 2014 Phase-I clinical trials in Bacterial infections (in volunteers) in Australia (IV)

SYNTHESIS

PATENT

IN2015MU287

PATENT

WO2013180197

Example 59
(2S, 5R) -N- (2- aminoethoxy) -7-oxo-6- (sulfooxy) 1,6-diazabicyclo [3.2.1] octane-2-carboxamide (II-059)

Step 1
tert- butyl {2 – [({[(2S, 5R) -6- Benzyloxy-7-oxo-1,6-diazabicyclo [3.2.1] oct-2-yl] carbonyl} amino) oxy] ethyl } carbamate

Acid of Example 9 or 16 (6b, 1.34g, 4.87mmol) in methylene chloride (35mL) solution of triethylamine (2.71mL), N- ethyl -N ‘- (3- dimethylaminopropyl) carbodiimide hydrochloride (1.41g), 1- hydroxybenzotriazole monohydrate (1.15g), were added tert- butyl of Reference Example 9, wherein 2- (amino-oxy) ethyl carbamate (1.12g), room temperature It was stirred overnight Te.Water was added to the reaction solution to a residue obtained by concentration under reduced pressure, and extracted with ethyl acetate. The resulting organic layer with 0.1M hydrochloric acid, saturated aqueous sodium bicarbonate solution, washed with saturated aqueous sodium chloride solution, dried over anhydrous sodium sulfate, filtered and concentrated.The resulting residue was purified by silica gel column and purified by chromatography (hexane / ethyl acetate = 8 / 2-0 / 10) to give the title compound 1.77g (84% yield).
[Α] _D ²⁰ -0.08 ° (c 0.29, CHCl _3); ¹ H NMR (400 MHz, CDCl _3), δ: 1.44 (s, 9H), 1.56-1.70 (m, 1H), 1.90-2.09 (m , 2H), 2.25-2.38 (m, 1H), 2.76 (d, J = 11.6 Hz, 1H), 3.03 (br d, J = 11.6 Hz, 1H), 3.24-3.47 (m, 3H), 3.84-4.01 (m, 3H), 4.90 (d, J = 11.6 Hz, 1H), 5.05 (d, J = 11.6 Hz, 1H), 5.44 (br s, 1H), 7.34-7.48 (m, 5H), 9.37 (br s, 1H); MS m / z 435 [M ⁺ H] +; enantiomeric excess of 99.9% or higher ee (CHIRALPAK AD-H, 4.6x150mm, hexane / ethanol = 2/1, UV210nm, flow rate 1mL / min, retention time 4.95min (2R, 5S), 6.70min (2S, 5R).

Step 2
tert- butyl {2 – [({[(2S, 5R) -1,6- -6- hydroxy-7-oxo-diazabicyclo [3.2.1] oct-2-yl] carbonyl} amino) oxy] ethyl} carbamate

Compound of the above Step 1 (3.91g, 9.01mmol) in methanol (80mL), 10% palladium on carbon catalyst (50% water, 803mg) was added, under hydrogen atmosphere and stirred for 45 minutes. The reaction mixture was filtered through Celite, then concentrated under reduced pressure, to give 3.11g of the title compound (quantitative).
¹ H NMR (400 MHz, CD ₃ OD), ^δ: 1.44 (s, 9H), 1.73-1.83 (m, 1H), 1.86-1.99 (m, 1H), 2.01-2.12 (m, 1H), 2.22 ( br dd, J = 15.0, 7.0 Hz, 1H), 3.03 (d, J = 12.0 Hz, 1H), 3.12 (br d, J = 12.0 Hz, 1H), 3.25-3.35 (m, 2H), 3.68-3.71 (m, 1H), 3.82-3.91 (m, 3H); MS m / z 345 [M ⁺ H] +.

Step 3
(2S, 5R) -N- (2- aminoethoxy) -7-oxo-6- (sulfooxy) 1,6-diazabicyclo [3.2.1] octane-2-carboxamide The above step 2 compound (3. 09g, in methylene chloride (80mL) solution of 8.97mmol), 2,6- lutidine (3.20mL), sulfur trioxide – was added pyridine complex (3.58g), and stirred at room temperature overnight. The reaction mixture was poured into half-saturated aqueous sodium bicarbonate solution, and washed the aqueous layer with chloroform, and tetrabutylammonium hydrogen sulfate (3.47g) and chloroform (30mL) was added to the aqueous layer and stirred for 10 minutes. After extracting the aqueous layer with chloroform, drying the resulting organic layer over anhydrous sodium sulfate, filtered, concentrated under reduced pressure tetrabutylammonium tert- butyl {2 – [({[(2S, 5R) -7- oxo – 6- (sulfooxy) 1,6-diazabicyclo [3.2.1] oct-2-yl] carbonyl} amino) oxy] ethyl} carbamate was obtained 5.46g (91% yield).
¹ H NMR (400 MHz, CDCl _3), ^δ: 1.01 (t, J = 7.4 Hz, 12H), 1.37-1.54 (m, 8H), 1.45 (s, 9H), 1.57-1.80 (m, 9H), 1.85-1.98 (m, 1H), 2.14-2.24 (m, 1H), 2.30-2.39 (m, 1H), 2.83 (d, J = 11.6 Hz, 1H), 3.20-3.50 (m, 11H), 3.85- 3.99 (m, 3H), 4.33-4.38 (m, 1H), 5.51 (br s, 1H), 9.44 (br s, 1H); MS m / z 425 [M-Bu ₄ N ⁺ 2H] +.

The tetrabutyl ammonium salt (5.20g, 7.82mmol) in methylene chloride (25mL) solution of under ice-cooling trifluoroacetic acid (25mL), and the mixture was stirred for 1 hour at 0 ℃. The reaction mixture was concentrated under reduced pressure, washed resulting residue with diethyl ether, at aqueous sodium bicarbonate was adjusted to pH7, it performs an octadecyl silica gel column chromatography (water), after freeze-drying, 1.44g of the title compound The obtained (57% yield).
[Α] _D ²⁴ -63.5 ° (c 0.83, H ₂ O); ¹ H NMR (400 MHz, _{D 2} O), δ: 1.66-1.76 (m, 1H), 1.76-1.88 (m, 1H), 1.91 -2.00 (m, 1H), 2.00-2.08 (m, 1H), 3.02 (d, J = 12.0 Hz, 1H), 3.15 (t, J = 5.0 Hz, 2H), 3.18 (br d, J = 12.0 Hz , 1H), 3.95 (dd, J = 7.8, 2.2 Hz, 1H), 4.04 (t, J = 5.0 Hz, 2H), 4.07 (dd, J = 6.4, 3.2 Hz, 1H); MS m / z 325 [ M ⁺ H] +.

PATENT

WO2016116878

ANTIBACTERIAL COMPOSITIONS OF A BETA-LACTAMASE INHIBITOR WITH A CEPHALOSPORINAbstract:

PATENT

WO 2016120752, WOCKHARDT, NEW PATENT, Nacubactam

Formula (I), chemically known as (25, 5i?)-N-(2-aminoethoxy)-6-(sulfooxy)-7-oxo-l ,6-diazabicyclo[3.2.1 ]octane-2-carboxamide has antibacterial properties and is disclosed in PCT International Patent Application No. PCT/IB2013/053092, PCT/JP2013/064971 and PCT/IB2012/002675. The present invention discloses a process for preparation of a compound of Formula (I).

Formula (I)

(VII) (VIII) (IX)

Scheme 2

Example 1

Synthesis of fert-butyl-r2-(aminooxy) ethyllcarbamate (III)

Preparation of fert-butyl-2-hydroxy ethylcarbamate (VIII):

Formula (VIII)

To a stirred solution of ethanolamine (50.0 g, 0.8186 mol) in dichloromethane (1000 ml), was added triethylamine (124 g, 1.228 mol) at 0°C. After 10 minutes, di-teri-butyl dicarbonate (VII, 214.15 g, 0.9823 mol) was added drop wise at 0°C under continuous stirring. Then reaction mass was allowed to warm to 25°C and stirred further for 3 hours. After completion of reaction, the resulting reaction mixture was poured into water (250 ml) and the organic layer was separated and dried over anhydrous sodium sulfate. The dried organic layer was concentrated under reduced pressure to obtain 130 g of the titled product as colorless oil in 98% yield.

Analysis:

Mass: 162 (M+l); for Molecular Weight of 161.2 and Molecular Formula of C7H15NO3.

1H NMR (400MHz, CDC1₃): δ 4.92(br s,lH), 3.72-3.68(q,2H), 3.30-3.26(q,2H), 2.33(br s,lH), 1.44(s,9H).

Preparation of A⁷-Boc-2-(2-aminoethoxy)isoindoline-l,3-dione (IX):

To a stirred solution of teri;butyl-2-hydroxy-ethylcarbamate (VIII, 50 g, 0.3106 mol) in tetrahydrofuran (500 ml), was added triphenylphosphine (89.5 g, 0.3416 mol) at 25°C. After stirring for 10 minutes, a solution of N-hydroxyphthalimide (50.66 g, 0.3106 mol) in dichloromethane (250 ml) was added to the reaction mass at 25 °C over a period of 10 minutes. After stirring for further 10 minutes, diisopropyl azodicarboxylate (69.1 g, 0.3416 mol) was added to the reaction mass in small portions (exothermic reaction was observed up to 34°C). The resulting reaction mass was stirred further at 25°C. After 16 hours, the reaction mass was concentrated under reduced pressure to obtain colorless oily material. The oily residue was diluted with diisopropyl ether (200 ml) and stirred for 30 minutes. The separated solid was filtered under suction. The filtrate was evaporated under reduced pressure and the residue subjected to di-isopropyl ether treatment (200 ml). This procedure was repeated once again. The filtrate was concentrated to obtain a solid product. The obtained solid was washed with diisopropyl ether (50 ml) and dried under reduced pressure. This solid contains small amount of triphenylphosphine oxide, along with the product. This was used as such for the next reaction without further purification.

Analysis:

Mass: 307.2 (M+l); for Molecular Weight of 306.3 and Molecular Formula of Ci₅Hi₈N₂0₅; 1H NMR of purified material (400MHz, CDC1₃): 7.85-7.25 (m,4H), 5.62(br s,lH), 4.26-4.23(t,2H), 3.46-3.42(q,2H), 1.46(s,9H).

Step 3: Preparation of fert-butyl-[ -(aminooxy) ethyl]carbamate (III):

Formula (III)

To a stirred solution of N-Boc-2-(2-aminoethoxy)isoindoline-l ,3-dione (IX, 97 g, 0.3167 mol) in dichloromethane (970 ml) was added hydrazine hydrate (31.7 g, 0.6334 mol) , at 0°C, drop wise, over a period of 45 minutes and the stirring continued further. After 2 hours, the reaction mass was filtered under suction. Filtrate was washed with water (485 ml), and the organic layer was diluted with an aq. solution of 10% potassium hydrogen sulfate (485 ml) and stirred for 15 minutes. The aqueous layer was separated, neutralized with solid sodium hydrogen carbonate and extracted with dichloromethane (2 x 485 ml). The organic layer was separated, dried over anhydrous sodium sulfate, filtered and concentrated under reduced pressure to obtain colorless oil, this was used as such for further reaction immediately (28g, overall yield of step II and step III was 60%)

Analysis:

Mass: 177.2 (M+l) for Molecular Weight of 176.2 and Molecular Formula of C7H16N2O₃.

Example 2

Synthesis of (25,5R)-jV-(2-aminoethoxy)-6-(sulfooxy)-7-oxo-l,6-diaza-bicvclor3.2.11octane-2- carboxamide (I)

Step 1: Preparation of (25,5R)-iV-(2-Boc-aminoethoxy)-6-(benzyloxy)-7-oxo-l,6-diaza-bicyclo[3.2.1]octane-2-carboxamide (IV):

To a clear solution of sodium (25,5i?)-6-(benzyloxy)-7-oxo-l,6-diazabicyclo[3.2.1]octane-2-carboxylate (II, 42.67 g, 0.143 mol; prepared according to the procedure disclosed in Indian Patent Application No. 699/MUM/2013) in water (426 ml) was added EDC.HC1 (67.1 g, 0.349 mol) at 15°C

under stirring. After 10 minutes, a solution of teri-butyl-[2-(aminooxy) ethyl]carbamate (III, 28.0g, 0.159 mol; prepared as per the literature procedure depicted in Scheme 2) in dimethylformamide (56 ml) was added drop wise at 10°C under continuous stirring. The temperature of the reaction mass was allowed to warm to 25°C and then HOBt (21.5g, 0.159 mol) was added in small portions over a period of 15 minutes and the resulting mixture was further stirred at room temperature for 16 hours. The reaction was continuously monitored using thin layer chromatography using mixture of acetone and hexane (35 :65) as solvent system. After completion of reaction, the resulting mixture was filtered and the residue was washed with water (130 ml). The obtained white residue was suspended in water (130 ml) and the mixture stirred at 50°C for 3 hours. The resulting suspension was filtered, the residue dried under reduced pressure to obtain 51 g of (2S,5R)-N-(2-Boc-aminoethoxy)-6-(benzyloxy)-7-oxo-l ,6-diaza-bicyclo[3.2.1]octane-2-carboxamide (IV) as off white solid in 73% yield.

Analysis:

Mass: 433.4 (M-l ); for Molecular Weight of 434.5 and Molecular Formula of C21H₃0N4O6;

1H-NMR (400MHz, CDC1₃): δ 9.32 (br s, 1H), 7.41 -7.26(m,5H), 5.41(br s, 1H), 5.06-4.88(dd, 2H), 3.98-3.96(d,lH), 3.91-3.90(m,2H), 3.39(m, 1H), 3.31-3.26(m, 2H), 3.04-3.01(d,lH), 2.77-2.74(d, 1H), 2.33-2.28(m, 1H), 2.03-1.93(m, 2H), 1.67-1.64(m, 1H), 1.44(s, 9H);

Purity as determined by HPLC: 99.4%.

Step 2: Preparation of (2S,5R)-iV-(2-Boc-aminoethoxy)-6-(hydroxy)-7-oxo-l,6-diaza-bicyclo[3.2.1]octane-2-carboxamide (V):

A solution of (25,5i?)-N-(2-Boc-aminoethoxy)-6-(benzyloxy)-7-oxo-l ,6-diaza-bicyclo[3.2.1] octane-2-carboxamide (IV, 38 g, 0.0875 mol) in a mixture of dimethylformamide and dichloromethane (2: 8, 76 ml: 304 ml), containing 10% Pd/C (7.6 g, 50% wet) was hydrogenated at 50 psi hydrogen atmosphere at 25°C for 3 hours. The resulting mixture was filtered through a celite pad. The residue was washed with dichloromethane (75 ml). The solvent from the combined filtrate was evaporated

under reduced pressure to obtain 30 g (25,5i?)-N-(2-Boc-aminoethoxy)-6-(hydroxy)-7-oxo-l ,6-diaza-bicyclo[3.2.1 ]octane-2-carboxamide (V) as an oil, which was used as such for the next reaction without further purification.

Analysis:

Mass: 343.3 (M-l ) for Molecular Weight of 344.3 and Molecular Formula of C14H24N4O6.

Step 3: Preparation of (25,5R)-iV-(2-Boc-aminoethoxy)-6-(sulfooxy)-7-oxo-l,6-diaza-bicyclo[3.2.1]octane-2-carboxamide,tetrabutyl ammonium salt (VI):

To a stirred solution of (25,5i?)-N-(2-Boc-aminoethoxy)-6-(hydroxy)-7-oxo-l ,6-diaza-bicyclo[3.2.1 ]octane-2-carboxamide (V, 30.0 g, 0.0875 mol) in dimethylformamide (150 ml) was added sulphur trioxide dimethylformamide complex (16.06 g, 0.105 mol) in one portion, at 10°C. The reaction mass was stirred at the same temperature for 30 minutes and then allowed to warm to room temperature. After 2 hours, a solution of tetrabutylammonium acetate (31.6 g, 0.105 mol) in water (95 ml) was slowly added to the reaction mixture and stirred for another 2 hours. The solvent from the reaction mixture was evaporated under reduced pressure to obtain an oily residue. The oily mass was co-evaporated with xylene (2 x 60 ml) to obtain thick mass. This mass was partitioned between 1 : 1 mixture of dichloromethane (300 ml) and water (300 ml). The organic layer was separated and the aqueous layer re-extracted with dichloromethane (150 ml). The combined organic extracts were washed with water (3 x 150 ml) and dried over anhydrous sodium sulphate. The solvent was evaporated under reduced pressure and the resulting oily mass was triturated with ether (3 x 60 ml). Each time the ether layer was decanted and the residue was finally concentrated under reduced pressure to obtain the sticky mass. The so obtained material was purified by column chromatography over silica gel using mixture of methanol and dichloromethane as elution solvent. The solvent from the combined fractions was evaporated to obtain 47.5 g of (25,5i?)-N-(2-Boc-aminoethoxy)-6-(sulfooxy)-7-oxo-l ,6-diaza-bicyclo[3.2.1 ]octane-2-carboxamide,tetrabutyl ammonium salt as white foam in 70% yield.

Analysis:

Mass: 423.4 (M-l) as free sulphonic acid; for Molecular Weight of 665.9 and Molecular Formula of C₃0H59N5O9 S;

1H- NMR (400MHz, CDC1₃): δ 9.52(br s, 1H), 5.53(br s, 1H), 4.33(s, 1H), 3.95-3.92(m,3H), 3.37-3.27(m, 1 1H), 2.87-2.84(d, 1H), 2.35-2.30(m, 1H), 2.17(m, 1H), 1.96-1.88(m, 2H), 1.74-1.60(m,8 H), 1.47-1.40(m, 17H), 1.02-0.98(m, 12H).

Step 4: Preparation of (2S R)-iV-(2-aminoethoxy)-6-(sulfooxy)-7-oxo-l,6-diaza-bicyclo[3.2.1]octane-2-carboxamide (I):

Formula (I)

To a stirred solution of (2S,5i?)-N-(2-Boc-aminoethoxy)-6-(sulfooxy)-7-oxo-l ,6-diaza-bicyclo[3.2.1 ]octane-2-carboxamide, tetrabutyl ammonium salt (VI, 17 g, 0.0225 mol) in dichloromethane (85 ml) was added trifluoroacetic acid (85 ml) drop wise at -10°C over a period of 45 minutes. The resulting mass was further stirred at same temperature for 1 hour. The resulting reaction mixture was poured into cyclohexane (850 ml), stirred well for 30 minutes and the separated oily layer was collected. This procedure was repeated one more time and finally the separated oily layer was added to tert-butyl methyl ether (170 ml) under vigorous stirring at 25°C. The ether layer was removed by decantation from the precipitated solid. This procedure was repeated twice again with tert-butyl methyl ether (2 x 170 ml). The solid thus obtained was stirred with fresh dichloromethane (170 ml) for 30 minutes and filtered. The residual solid was dried at 45°C under reduced pressure to yield 7.3g of the titled compound in crude form. The obtained solid was further dissolved in water, (7.3 ml) and to this solution was added basic resin (Amberlyst A-26 -OH ion exchange resin, 4.4 g) under stirring. After 0.5 hour, the resin was filtered and to the filtrate isopropanol (51 ml) was added slowly at 25°C. The solution was further stirred for 12 hours. The separated solid was filtered and washed with additional isopropanol (7.5 ml) and dried under reduced pressure to obtain 4.3 g of (2S ,5R)-N-(2-aminoethoxy)-6-(sulfooxy)-7-oxo-l ,6-diaza-bicyclo[3.2.1 ]octane-2-carboxamide as off-white solid in 52 % yield.

Analysis:

Mass: 323.1 (M-l); for Molecular Weight of 324.31 and Molecular Formula of C₉H16N4O7S; 1H-NMR (400MHz, D₂0): δ 4.07-4.06(d, 1H), 4.05-4.03(t, 2H), 3.96-3.94(d, 1H), 3.20(br s, 1H), 3.16-3.13(t, 2H), 3.02-2.99(d, 1H), 2.04-1.68(m, 4H);

Purity as determined by HPLC: 94.88%.

REF

http://www.pewtrusts.org/~/media/assets/2015/02/antibioticsinnovationproject_datatable_201502_v3.pdf?la=en

/////////////IN2015MU287, WO-2016120752, nacubactam, WOCKHARDT, NEW PATENT, WK ?, WK-?, WK?,  CAS 1452458-86-4, C₉ H₁₆ N₄ O₇ S, 324.31, Beta lactamase inhibitor, Roche, Meiji Seika Pharma,  Fedora Pharmaceuticals, nacubactam hydrate , PHASE 1, A diazabicyclooctane beta-lactamase inhibitor, bacterial infection, July 2016,  phase 1 clinical development, RG-6080, 1452458-86-4, FPI-1459,  OP-0595, Phase I ,  β-lactamase inhibitor, bacterial infections, Fedora parmaceuticals, Meiji Seika Pharma

NCCONC(=O)[C@@H]2CC[C@@H]1C[N@]2C(=O)N1OS(=O)(=O)O

Dolutegravir

• Soltegravir

2H-Pyrido[1′,2′:4,5]pyrazino[2,1-b][1,3]oxazine-9-carboxamide, N-[(2,4-difluorophenyl)methyl]-3,4,6,8,12,12a-hexahydro-7-hydroxy-4-methyl-6,8-dioxo-, (4R,12aS)

(3R,11aS)—N-[(2,4-Difluorophenyl)methyl]-6-hydroxy-3-methyl-5,7-dioxo-2,3,5,7,11,11a-hexahydro[1,3]oxazolo[3,2-a]pyrido[1,2-d]pyrazine-8-carboxamide

(4R,12aS)-N-(2,4-difluorobenzyl)-7-hydroxy-4-methyl-6,8-dioxo-3,4,6,8,12,12a-hexahydro-2H-pyrido[1′,2′:4,5]pyrazino[2,1-b][1,3]oxazine-9-carboxamide
Trade Name:Tivicay
Synonym:GSK1349572, S-349572, GSK572
Date of Approval: August 12, 2013 (US)
Indication:HIV infection
Drug class: Integrase strand transfer inhibitor
Company: ViiV Healthcare,GlaxoSmithKline

INNOVATOR …ViiV Healthcare 
CAS number: 1051375-16-6

1051375-19-9 (Dolutegravir Sodium)

MF:C20H19F2N3O5
MW:419.4

Chemical Name: (4R,12aS)-N-[(2,4-difluorophenyl)methyl]-7-hydroxy-4-methyl-6,8-dioxo-3,4,6,8,12,12a- hexahydro-2H-pyrido[1′,2′:4,5]pyrazino[2,1-b][1,3]oxazine-9-carboxamide
Patent: US8129385
Patent expiration date: Oct 5, 2027
PCT patent application: W02006116764

ドルテグラビルナトリウム
Dolutegravir Sodium

C₂₀H₁₈F₂N₃NaO₅ : 441.36
[1051375-19-9]

Dolutegravir (DTG, GSK1349572) is an integrase inhibitor being developed for the treatment of human immunodeficiency virus (HIV)-1 infection by GlaxoSmithKline (GSK) on behalf of Shionogi-ViiV Healthcare LLC. DTG is metabolized primarily by uridine diphosphate glucuronyltransferase (UGT)1A1, with a minor role of cytochrome P450 (CYP)3A, and with renal elimination of unchanged drug being extremely low (< 1% of the dose).

Dolutegravir sodium was approved by the U.S. Food and Drug Administration (FDA) on Aug 12, 2013, then approved by European Medicine Agency (EMA) on Jan 16, 2014, and approved by Pharmaceuticals and Medical Devices Agency of Japan (PMDA) on Mar 24, 2014, then approved by Center For Drug Evaluation (CFDA) on Dec 30, 2015. It was co-developed by GlaxoSmithKline & ViiV Healthcare Corporation, then marketed as Tivicay^® by ViiV Healthcare in the US and EU and by GlaxoSmithKline & ViiV Healthcare Corporation in JP.

Dolutegravir sodium is an integrase inhibitor which blocks HIV replication by preventing the viral DNA from integrating into the genetic material of human immune cells (T-cells). This step is essential in the HIV replication cycle and is also responsible for establishing chronic infection. It is in combination with other antiretroviral agents for the treatment of HIV-1 infection in adults and children aged 12 years and older and weighing at least 40 kg.

Tivicay^® is available as film-coated tablet for oral use, containing 50 mg of free Dolutegravir. The recommended dose is 50 mg Dolutegravir once daily without regards to meals.

APPROVALS