Methyl cholanate

Methyl cholanate — Methyl 3-kcto-7r, l 2 -dihydroxycholanate (90%) Geraniol — Geranial (97%)... 

The selective oxidation of the 3-hydroxyl group of methyl cholanate is noteworthy. Also acetyl, ethyleneketal, and ethylenethioketal groups are stable to the reagent. 

Degradation of the bile acid side chain. Fetizon et al. have described a convenient new procedure for degradation of the side chains of bile acids and lanosterol. The method is illustrated for methyl cholanate (1). The first steps ... 

The methyl ester of the acid can very conveniently be prepared by esterifying in ten parts of methyl alcohol with hydrogen chloride. After boiling for quite a short time, the cold solution, saturated with hydrogen chloride, is poured into a large volume of dilute sodium carbonate solution, and the ester, which is precipitated in solid form, is dried and recrystallised from a little dilute methyl alcohol. Other compounds which may suitably be prepared are dehydrocholic add, cholatrienic add, and cholanic add. 

Roda A, Aldini R, Grigolo B et al. (1988) 23-Methyl-3a,7b-dihydroxy-5b-cholan-24-oic acid Dose-response study of biliary secretion in rat. Hepatol 8 1571-1576 Paglietti G, Sanna P, Carta A et al. (1994) Choleretic activity of 3-[ring substituted benzotriazol-l(2)yl]alkanoic and alkenoic adds. Farmaco 49 693-702 Peana A, Satta M, Luigi-Moretti MD, Orecchioni M (1994) A study on choleretic activity of Salvia desoleana essential oil. Planta Med 60 478 179... 

The first case of the exclusive introduction of bromine at a site unfavourable for enolization has been reported.159 Reaction of methyl 3-oxo-5/3-cholanate with two equivalents of iodine monobromide can be seen to take place in two distinct stages after 2 h the expected 4/3-bromo-derivative can be isolated, but after 5 days the only product isolated is the equatorial methyl 2/8-bromo-3-oxo-5/3-cholanate, resulting from debromination at C-4 and rebromination at C-2. 

Preparation of methyl 3,3-dihydroperoxy-7a,12a-diacetoxy-5p-cholan-24-oate... 

Preparation of methyl 7a,12a-diacetoxy-5p-cholan-24-oate-3- spiro-6 -(1, 2, 4, 5 -tetraoxacyclohexane)- 3 -spirocyclopentane... 

The most significant, from a drug perspective, are the cholane, pregnane, androstane, and estrane systems. When a carbon, such as a methyl group, is lost from the nucleus, the term nor is used. 

Syntheses were reported161 for the 20-epimers of 21-nor-5a-cholane-20,24-diol (187) from the methyl ester (186). Cholest-4-en-3-one was converted162 into 24-hydroxychol-4-en-3-one in one step by treatment with CF3CO3H-H2SO4 at... 

The lactone (31), obtainable in three steps from cholanic acid, served as the starting point in a different approach. Phosphorus oxychloride-pyridine dehydration of the corresponding hydroxy-methyl ester afforded a complex mixture of unsaturated esters in which the cis and trans non-conjugated esters (32) predominated Hydrolysis of the entire mixture and treatment of the mixture of free acids with iV-bromosuccinimide gave the new buf-20(22)-enolide (33). DDQ dehydrogenation of (33) could be controlled to yield either the desired bufa-... 

R = COOCH, methyl (20S,22R)-22li-h droxy-6fi-methoxv-24-nor-3,5-cvclo-5x-cholan-23-oate ... 

Deoxycholic Acid, (3ct,5t3,I2a) 3,I2-Dihydroxy-5 cholan-2d <>ic acid- l70-(i-methyl-3-carboxypropyl)etio-cbolane-3a, 12 -diol desoxycholic acid, mol wt... 

Bromination of methyl 3-oxO Sp-cholanate (1). Bromination of this 5 3-ketosteroid with IBr (2 eq.) in HOAc gives the expected 4j3-bromo ketone (2). On standing, (2) rearranges slowly to the 2 3-bromo ketone (3) in 50% yield... 

Reaction of steroidal tosylates with KNO2 in DMSO or DMF gave reasonable yields of alcohols with inverted configuration. The previously reported epi-merization at C-3 during Raney nickel-catalysed hydrogenation of methyl 3, 1 a-dihydroxy-12-oxo-5/8-cholanate was incorporated in a report of the synthesis of 3/3,7a,12j8-trihydroxy-5/3-cholanic acid and the 3a,7a,12/3-trihydroxy-analogue. Conversion of mestranol into epimestranol was achieved by treatment of the 17-mesylate with silver nitrate in aqueous THF. ... 

Although less effective than methyl(trifluoromethyl)dioxirane (TFDO), oxyfunctionalization of unactivated methine C-Hs with dimethyldioxirane (DDO) is feasible for various substituted steroids related to the 5/)-cholane and 5a-cholestane series to give novel mono- and dihydroxylated steroids. The reactivity and site selectivity of oxyfunctionalization is affected conspicuously by the structural and steric environments of the target methine carbon atoms. This nonenzymatic procedure may be advantageously applied to selective and short-course s)mtheses of bioactive steroids. Thus, the major reaction product of methyl... 

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