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3/?-Hydroxy-5/?-cholanoic acid

In a separate study, Branden (11) modelled the active site+ substrate interactions of ADH and several 36-and 3a-hydroxy steroids, based on the kinetic work of others (4,5). He showed that 3S-hydroxy-53-cholanoic acid fits in the active site rather... [Pg.190]

Hydride reduction of 3-oxo-A-nor-5jff-cholanoic acid afforded a preponderance of the 3a-hydroxy-compound, although the ratio of 3a 3) alcohols is less than with the normal six-membered homologues. Lithium-ammonia reduction afforded equal amounts of 3a- and 3)5-epimers. AB-Dinor-cholestenone and -testosterone have been prepared by the following sequence ... [Pg.451]

As noted earlier, bile acids were among the first steroids to be obtained in pure crystalline form. These compounds played an important role in the effort devoted to divining the structure of steroids. Bile acids as a result acquired a sizeable number of trivial names, most of which gave little information as to their chemical structure. One approach to systematic names is based on the hypothetical cholanoic acid 8-1 (Scheme 8). Bile acids are then named as derivatives of this structure using the mles used for other classes of steroids. Note the cis A-B ring fusion in this series. The systematic name for 8-2, lithocholic acid, is then simply 3a-hydroxy-5/3-cholanic acid. Chenodeoxycholic acid, 8-3, becomes 3a,7a-dihydroxy-5/3-cholanic acid. The predominant acid in bile, 8-3, is cholic acid itself, or, 3a,7a,12a-trihydroxy-5 )8-cholanic acid. [Pg.8]

TThe following systematic names are given to steroids and bile acids referred to by trivial names cholestanol, 5a-cholestan-3/5-ol cholic acid, 3a,7a,12a-trihydroxy-5j3-cholanoic acid hyocholic acid, 3a,6a,7a-trihydroxy-5/S-cholanoic acid a-muricholic acid, 3a,6/S,7a-trihydroxy-5/S-cholanoic acid /5-muricholic acid, 3a,6/S,7/S-trihydroxy-5/S-cholanoic acid allocholic acid, 3a,7a,12a-trihydroxy-5a-cholanoic acid chenodeoxycholic acid, 3a,7a-dihydroxy-5/5-cholanoic acid deoxycholic acid, 3a,12a-dihydroxy-5iS-cholanoic acid allochenodeoxycholic acid, 3a,7a-dihydroxy-5a-cholanoic acid allodeoxycholic acid, 3a,12a-dihydroxy-5a-cholanoic acid lithocholic acid, 3a-hydroxy-5/5-cholanoic acid. [Pg.1]

In the guinea pig, 3a-hydroxy-7-oxo-5/9-cholanoic acid is partly a primary bile acid and partly a secondary bile acid formed from chenodeoxycholic acid (Chapter 11 in this volume) The pathway for the formation of 3a-hydroxy-7-oxo-5/9-cholanoic acid in the liver has not been established. It might be mentioned that 3/3-hydroxy-5-cholesten-7-one is not a precursor of this acid (110). [Pg.19]

Fig. 2. Possible pathways for primary bile salt synthesis in man compiled from various sources (see text). V, Cholesterol VI, cholest-5-ene-3i3,7a-diol VII, 7a-hydroxycholest-4-en-3-one VIII, 7a-hydroxy-5/S-cholestan-3-one IX, 5/3-cholestane-3a,7a-diol X, 3a,7a-dihydroxy-5/3-cholestanoic acid XI, 3a,7a-dihydroxy-5/5-cholanoic acid (chenodeoxycholic acid) XII, 7a,12a-dihydroxy-cholest-4-en-3-one XIII, 7a,12a-dihydroxy-5/3-cholestan-3-one XIV, 5 -cholestane-3a,7a,12a-triol XV, 3a,7a,12a-trihydroxy-5/5-cholestanoic acid XV, 3a,7a,12a-trihydroxy-5/3-cholanoic acid XVI, 3a,7a,12a-trihydroxy-5/3-cholanoic acid (cholic acid). Fig. 2. Possible pathways for primary bile salt synthesis in man compiled from various sources (see text). V, Cholesterol VI, cholest-5-ene-3i3,7a-diol VII, 7a-hydroxycholest-4-en-3-one VIII, 7a-hydroxy-5/S-cholestan-3-one IX, 5/3-cholestane-3a,7a-diol X, 3a,7a-dihydroxy-5/3-cholestanoic acid XI, 3a,7a-dihydroxy-5/5-cholanoic acid (chenodeoxycholic acid) XII, 7a,12a-dihydroxy-cholest-4-en-3-one XIII, 7a,12a-dihydroxy-5/3-cholestan-3-one XIV, 5 -cholestane-3a,7a,12a-triol XV, 3a,7a,12a-trihydroxy-5/5-cholestanoic acid XV, 3a,7a,12a-trihydroxy-5/3-cholanoic acid XVI, 3a,7a,12a-trihydroxy-5/3-cholanoic acid (cholic acid).
With isotopically labeled primary bile salts, cholate and chenodeoxycholate, it is possible to show that in addition to deoxycholate a wide variety of secondary bile salts are derived from cholate, the chief ones being 12a-hydroxy-3-keto-5/ -cholanoic acid, 3), 12a-dihydroxy-5) -cholanoic acid, 3a-hydroxy-12 keto-5/5-cholanoic acid, and 3/ -hydroxy-12-keto-5j -cholanoic acid (30). A smaller number are derived from chenodeoxycholate, mainly lithocholate, 3/ -hydroxy-5i -cholanoic acid, and 3-keto-5i -cholanoic acid (31). The secondary bile acids which have been identified in man are listed in Table III. [Pg.62]

Confirms cholanoic acid (C24) structure Confirms homocholanoic acid (C25) structure Characteristic loss in 3P-hydroxy-A structures Characteristic of 12-oxo cholanoates Indicates cholestanoic side chain with A bond or -OTMS Confirms cholestanoic acid (C27) structure Characteristic of C29-dicarboxyhc side chain structure Establishes C-ring substitution Observed in C-24 hydroxy cholestanoic acids... [Pg.302]

A derivative of hyodeoxycholic acid, 3a-hydroxy-6 keto 5a-cholanoic acid, was isolated by Fernholz (42) from hog bile. Although this acid has been repeatedly referred to as a component of hog bile, it is most probably an artifact produced from the 6-keto-5/3 acid by alkaline hydrolysis of the conjugates present in bile. [Pg.56]

In a recent report Nakada et al. (89) detailed the preparation of 3,7-dioxo-5a-cholanoic acid (m.p. 185-187 °C) from 3 -hydroxy-7-keto-chol-5-enoic acid obtained from oxidation of 3/3-hydroxy-chol-5-enoic acid with CrOg and subsequent reduction. Reduction of this material should provide the 3jS-epimer of allochenodeoxycholic acid and its 7p-epimer. [Pg.77]

Alkaline hydrolysis of fresh hog bile provides access to 3a-hydroxy-6-oxo-5a-cholanoic acid (about 3 g/1.5 liter of bile) (92, 93, 13). Figure 11 summarizes the routes to the four epimeric 3,6-diols from this acid. Kawa-nami (94) has studied the susceptibility of the hydroxyl groups of this series to NBS and concludes the following 6 3 (a)>3/S(e)>6a(e). Corbellini et al. (95, 96) and Ziegler (97) have investigated interconversions of isomers at Cg through the mesylates and tosylates. [Pg.77]

Anderson and Haslewood (19) explored the preparation of these derivatives from 3 -hydroxy-6-keto-5rt-cholanoic acid in a manner analogous to that outlined in Fig. 6. The known 3a,7 -dihydroxy-6-keto-5a-cholanoic acid (90) was esterified, and the product converted to a crystalline ethylene thioketal. Treatment of the latter with Raney nickel provided allolithocholic acid and several fractions of unidentified material. From one of these fractions an acid (A) was obtained, m.p. 240-241 °C [ ]D+60i 1 from the succeeding fraction an acid (B) was converted to the methyl ester (C), m.p. 156-158°C [a]D4-58 1 °. The Md for (C) (Found-1-235) agrees reasonably well with the calculated value for a 3/3,7(3-diol (4-190) or a 3a,7 3-diol (4-197). In a similar sequence of reactions Ziller (91) obtained a methyl ester, m.p. 158-159°C RRe 1.42 on 3% QF-1 free acid, m.p. 240-241 °C. Subsequent experiments have shown that the monohydro.xy acids derived from this diol are the 3p- and 7 -ols, suggesting that this acid is the unreported 3j3,7/3-dihy-droxy-5a-cholanoic acid (170). [Pg.77]

Support for the concept of an unsaturated intermediate in the formation of allo-acids is provided by recent experiments of Yamasaki et at. (98, 89). After administration of 3-ketochol-4-enoic-24- - C acid to rats and examination of the biliary metabolites, all four isomers of 3-hydroxycholanoic acid were identified other di- and trihydroxy acids were not investigated. Of the four possible 3-hydroxy-isomers about twice as much lithocholate was present as each of the other isomers. Similar results were obtained following administration of 3/3-acetoxychol-5-enoic-24-i- C acid in addition, 3f,6 -dihydroxy-5a-cholanoic acids were obtained. Yamasaki et al. (89) propose that a 3/3-dehydrogenase converts the 3/3-hydroxy-J -cholenoic acid to the a,/3-unsaturated ketone from which both 5 and 5 acids are derived, whereas hydroxylation of the above acid provides the diol from which only 5 acids are produced, somewhat analogous to the scheme of metabolism proposed by Mitropoulos and Myant (132) for the formation of chenodeoxycholic acid and the muricholic acids. [Pg.85]

Reversed phase partition conditions are established with alkylated Sephadex LH-20 containing 50% (w/w) of Cji-Cj4 alkyl chains, when solvents such as methanol-water-ethylene chloride, 70 30 10, are used. With this system 3a-hydroxy-, 3/3-hydroxy-, and 3-keto-5p-cholanoic acids are completely separated in this order (65). The importance of liquid-gel chromatography in bile acid analysis is likely to increase during the next few years. [Pg.135]

Several experiments have been reportedon the biosynthesis of bile acids in rats administered [l- Hj]ethanol for labelling of the NADH and NADPH pools. The fact that deuterium was present in the 3P-position but not in the Sa-position of 3a-hydroxy-5a-cholanoic acid formed from 3-oxochol-4-en-24-oic acid indicated that different coenzyme pools are utilized in the reductions of the oxo-group and the double bond. This is in agreement with other observations.It is interesting that unidentified unsaturated monohydroxy bile acids have been isolated from patients with cholestatic liver disease. " ... [Pg.45]

Lithocholic acid 3a-hydroxy-5P-cholanoic add, or 3a-hydroxy-5p-cholan-24 c acid, M, 376.58, m.p. 185 C, [a]D + 32 ° (ethanol). L. a. is a monohydroxyla-ted steroid carboxylic add, and one of the bile acids. It has been isolated from the bile of man, cow, rabbit, sheep and goat, and is normally prepared from bovine bile. L.a. is formed from chenodeoxycholate by intestinal bacteria. It is absorbed and returned to the liver for secretion. It is not readily conjugated, and it is relatively toxic to the liver. L.a. may be important in the pathogenesis of liver damage following biliary sta-... [Pg.366]

Improved separations of bile acid methyl esters can be observed with increasing amounts of phenyl substituents in the stationary phase (5% in SE-52, 20% in PhSi-20, and 50% in OV-17). Positional and configurational isomers are better resolved than on SE-30 or OV-1 columns. For instance the valuable separation of the trimethylsilyl ethers of 3,6,7-substituted methyl cholanoates from the corresponding cholic acid derivative on OV-17 should be noted. The pronounced effect of a 7/3-hydroxy substituent on retention times on columns of SE-52 and PhSi-20 is noteworthy. The large separation factors between the diacetate derivatives of chenodeoxy- and ursodeo.xycholic acids may be most useful in work with bile acids of biological origin. [Pg.157]

Examples of mass spectra of derivatives of 3,6-, 3,7- and 3,12-dihydroxy-cholanoates are shown in Figs. 4 and 5. At the temperatures used in gas chromatography-mass spectrometry, molecular ions are seen only with the free hydroxy compounds and the trimethylsilyl ether derivatives (intensity usually less than one percent of base peak). Molecular ions with a relative intensity of 5-10% are obtained from the methyl esters or acids when a direct probe is used (14, 15). Loss of 2 and 4 mass units from the molecular ions of compounds with free hydroxyl groups is most probably thermal and is not seen at low temperatures. [Pg.224]


See other pages where 3/?-Hydroxy-5/?-cholanoic acid is mentioned: [Pg.700]    [Pg.39]    [Pg.700]    [Pg.192]    [Pg.2]    [Pg.63]    [Pg.119]    [Pg.154]    [Pg.269]    [Pg.78]    [Pg.81]    [Pg.84]    [Pg.134]    [Pg.138]    [Pg.146]    [Pg.146]    [Pg.223]    [Pg.266]    [Pg.266]    [Pg.625]    [Pg.625]    [Pg.67]    [Pg.232]    [Pg.238]   
See also in sourсe #XX -- [ Pg.194 ]




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