| 摘要 |
A process for preparing a form of chenodeoxycholic acid having a melting point of ca. 166 DEG C from the amorphous form of the acid or from the form melting at ca. 120 DEG C. The amorphous or low melting forms of chenodeoxycholic acid, in a suspension in water, are seeded with preprepared crystalline acid of the high melting form and the acid product treated, in suspension, at a temperature of not greater than 85 DEG C to complete the conversion of the chenodeoxycholic acid to the high melting form. Crude chenodeoxycholic acid of the low melting form is purified by a process which involves forming a mixture of the crude acid, methanol, a base and a calcium or strontium salt, separating the precipitated crystalline calcium or strontium chenodeoxycholanate, dissolving the salt in a solution of acetic or propionic acid, diluting the solution with water to precipitate the free acid in purified form and recovering the purified acid.
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