process for purification of raw chenodesoxycholsaeure

摘要

1360354 Chenodeoxycholic acid UNION INTERNATIONAL CO Ltd 15 Jan 1973 [20 Jan 1972] 2803/72 Heading C2U Chenodeoxycholic acid (I) is purified by forming a mixture thereof with methanol, a base and a Ca or Sr salt (e.g. chloride or nitrate), separating and acidifying the precipitated Ca or Sr salt of I, and isolating the purified produce. The base may be an alkali metal hydroxides. ammonia, ammonium hydroxide, hydrazine hydrate or an organic nitrogenous base (a list of examples is provided). The preparation of I from cholic acid (II) by the sequence II-(a)#methyl cholate-(b)# methyl - 3α,7α - diacetoxy - 12α - hydroxy - 5#- cholanate-(c)#methyl - 3α,7α - diacetoxy - 12- oxo-5#-cholanate-(d)#I is effected with reactants as follows (a) MeOH/H 2 SO 4 ; (b) Ac 2 O/py in benzene, dioxan, THF, dimethyl sulphoxide or acetonitrile; (c) sodium chromate/H 2 O/ AcOH; (d) Wolff-Kishner, modified Wolff- Kishner or cathodic reduction followed by hydrolysis.