- Synthesis and structure-activity relationships in a series of antiinflammatory corticosteroid analogues, halomethyl androstane-17β- carbothioates and -17β-carboselenoates
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The preparation and topical antiinflammatory potencies of a series of halomethyl 17α-(acyloxy)-11β-hydroxy-3-oxoandrosta-1,4-diene-17β- carbothioates, carrying combinations of 6α-fluoro, 9α-fluoro, 16-methyl, and 16-methylene substituents, are described. Key synthetic stages were the preparation of carbothioic acids and their reaction with dihalomethanes. The carbothioic acids were formed from 17β-carboxylic acids by initial reaction with dimethylthiocarbamoyl chloride followed by aminolysis of the resulting rearranged mixed anhydride with diethylamine, or by carboxyl activation with 1,1'-carbonyldiimidazole (CDI) or 2-fluoro-N-methylpyridinium tosylate (FMPT) and reaction with hydrogen sulfide, the choice of reagent being governed by the 17α-substituent. Carboxyl activation with FMPT and reaction with sodium hydrogen selenide led to the halomethyl 16-methyleneandrostane-17β- carboselenoate analogues. Anti-inflammatory potencies were measured in humans using the vasoconstriction assay and in rats and mice by a modification the Tonelli croton oil ear assay. Best activities were shown by fluoromethyl and chloromethyl carbothioates with a 17α-propionyloxy group. S-Fluoromethyl 6α,9α-difluoro-11β-hydroxy-16α-methyl-3-oxo-17α-(propionyloxy)androsta- 1,4-diene-17β-carbothioate (fluticasone propionate, FP) was selected for clinical study as it showed high topical antiinflammatory activity but caused little hypothalamic-pituitary-adrenal suppression after topical or oral administration to rodents.
- Phillipps,Bailey,Bain,Borella,Buckton,Clark,Doherty,English,Fazakerley,Laing,Lane-Allman,Robinson,Sandford,Sharratt,Steeples,Stonehouse,Williamson
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- Improved synthesis of fluticasone propionate
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A novel process for the preparation of fluticasone propionate (1), a corticosteroid, is reported. In this paper, compound 2 was used as starting material to prepare 6 by using NaClO or NaBrO which was much cheaper than H 5IO6 as an oxidizing agent. Furthermore, toxic, expensive, and pollutive BrCH2F was replaced by AgNO3 and Selectfluor in decarboxylative fluorination.
- Zhou, Jiadi,Jin, Can,Su, Weike
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- METHODS OF PREPARING INTERMEDIATE OF FLUTICASONE PROPIONATE
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A method of preparing a thioic acid intermediate of fluticasone propionate includes: treating a 17β-[(N,N-dimethyl carbamoyl)thio]carbonyl compound in a solution including an alcohol and an alkali metal hydroxide, an alkaline-earth metal hydroxide, or a mixture thereof to cleave an amide from the 17β-[(N,N-dimethyl carbamoyl)thio]carbonyl compound; treating the solution to separate an aqueous portion; and adding an acid to the aqueous portion to obtain the thioic acid intermediate of fluticasone propionate. A method of preparing fluticasone propionate includes preparing the thioic acid intermediate of fluticasone propionate, and alkylating the thioic acid intermediate of fluticasone propionate to prepare the fluticasone propionate.
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- PROCESS FOR PREPARING FLUTICASONE PROPIONATE/FUROATE
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The present invention relates to an improved process for the preparation of substituted Fluticasone derivatives. The invention also reveals the processes for the purification of Fluticasones and related intermediates to provide the highly pure product.
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- METHOD FOR PREPARATION OF FLUTICASONE PROPIONATE
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Taught is a method for preparing S-fluoromethyl-6α,9α-difluoro-11β-hydroxy-16α-methyl-17α-propionyloxy-3-oxoandrosta-1,4-diene-17β-carbothioate (fluticasone propionate). The present method is simple, convenient, and mild, yields highly pure product, and is suitable for use commercially on a large scale.
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Page/Page column 2
(2008/12/05)
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- METHOD FOR THE PREPARATION OF FLUTICASONE PROPIONATE
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Taught is a method for preparing S-fluoromethyl-6α,9α- difluroro-11β-hydroxy-16α-methyl-17α- propionyloxy-3-oxoandrosta-1,4-diene-17β-carbothioate (fluticasone propionate). The present method is simple, convenient, and mild, yields highly pure product, and is suitable for use commercially on a large scale.
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(2010/11/30)
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- Convenient synthesis of s-fluoromethyl 6alpha, 9alpha-difluoro-11beta-hydroxy-16alpha-methyl-17alpha-propionyloxy-3-oxoandrosta-1,4-diene-17beta-carbothioate
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The present invention provides a convenient process for the preparation of S-fluoromethyl 6α,9α-difluoro-11β-hydroxy-16α-methyl-17α-propionyloxy-3-oxoandrosta-1,4-diene-17β-carbothioate, a compound of formula 1, comprising (a) treating 17β-[(N,N-dimethylcarbamoyl)thio]carbonyl-6α,9α-difluoro-11β-hydroxy-16α-methyl-17α-propionyloxy-3-oxoandrosta-1,4-diene, a compound of formula 3 with alkali metal carbonate-alcohol system to obtain 6α,9α-difluoro-11β-hydroxy-16α-methyl-17α-propionyloxy-3-oxoandrosta-1,4-diene-17β-carbothioic acid, a compound of formula 4; (b) reacting the compound of formula 4 with bromofluoromethane to yield the compound of formula 1. The present invention also provides an improved process for preparation of compound of formula 1 comprising (a) reacting 6α,9α-difluoro-11β-hydroxy-16α-methyl-3-oxo-17-(propionyloxy)androsta-1,4-dien-17β-carboxylic acid, a compound of formula 2, with N,N-dimethylthiocarbamoyl chloride in an inert aprotic solvent in the presence of an iodide catalyst and a base to give a compound of formula 3, (b) reacting the compound of formula 3 with a hydrosulfide reagent and bromofluromethane to obtain a compound of formula 1.
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(2010/02/14)
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- 17.BETA- (ALPHA-HYDROXY) -ESTERS OF ANDROSTANES AS INTERMEDIATES FOR THE PREPARATION FOR THE PREPARATION OF 17Β-FLUORINATED-ANDROSTANE ESTERS
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Process for the preparation of polyhalogenated steroids, in particular of androstanic fluoro derivatives corticosteroids by means of the formation of new androstanic S-hydroxy alkyl or aralkyl-17-carbothioate intermediates.
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