Title: Cholic Acid
CAS Registry Number: 81-25-4
CAS Name: (3a,5b,7a,12a)-3,7,12-Trihydroxycholan-24-oic acid
Synonyms: cholalic acid; 17b-(1-methyl-3-carboxypropyl)etiocholane-3a,7a,12a-triol
Trademarks: Colalin
Molecular Formula: C24H40O5
Molecular Weight: 408.57
Percent Composition: C 70.55%, H 9.87%, O 19.58%
Literature References: Occurs in conjugation with glycine or taurine in bile of most vertebrates. Extraction from beef bile: Wieland, Siebert,
Z. Physiol. Chem. 262, 1 (1939); laboratory procedure: Gattermann-Wieland,
Praxis des Organischen Chemikers (de Gruyter, Berlin, 40th ed., 1961) p 360. Structure and synthesis: Fieser, Fieser,
Steroids (Reinhold, New York, 1959).
Derivative Type: Monohydrate
Properties: Plates from dil acetic acid. Bitter taste with sweetish aftertaste. When anhydr, mp 198°. [a]D20 +37° (c = 0.6 in alcohol). pK = 6.4. Not precipitated by digitonin. Soly at 15° in water 0.28 g/l; in alcohol 30.56 g/l; in ether 1.22 g/l; in chloroform 5.08 g/l; in benzene 0.36 g/l; in acetone 28.24 g/l; in glacial acetic acid 152.12 g/l. Sol in solns of alkali hydroxides or carbonates.
Melting point: mp 198°
pKa: pK = 6.4
Optical Rotation: [a]D20 +37° (c = 0.6 in alcohol)
Derivative Type: Methyl ester
Molecular Formula: C25H42O5
Molecular Weight: 422.60
Percent Composition: C 71.05%, H 10.02%, O 18.93%
Properties: Crystals from 95% alcohol + water, mp 155-156°.
Melting point: mp 155-156°
Derivative Type: Ethyl ester
Molecular Formula: C26H44O5
Molecular Weight: 436.62
Percent Composition: C 71.52%, H 10.16%, O 18.32%
Properties: Crystals from ethyl acetate + petr ether, mp 162-163°.
Melting point: mp 162-163°
Derivative Type: Sodium salt
Synonyms: Sodium cholate
Molecular Formula: C24H39NaO5
Molecular Weight: 430.55
Percent Composition: C 66.95%, H 9.13%, Na 5.34%, O 18.58%
Properties: Crystals. Soly in water at 15°: >568.9 g/l.
CAUTION: The names "sodium cholate" and "sodium choleate" are sometimes used for mixtures of bile salts. The term "sodium choleate" is to be preferred for bile salts,
see Ox Bile Extract.
NOTE: The property of forming molecular compds is common to bile acids. For instance a blue molecular compd (C24H40O5I)4.KI.H2O, may be prepd by mixing an alcoholic soln of cholic acid and a soln of iodine in aq potassium iodide: Barger, Field,
J. Chem. Soc. 101, 1404 (1912).
Therap-Cat: Choleretic.
Keywords: Choleretic.
