Cholesterol gall-stones are a frequent disease which lack of effective treatment pharmaceuticals. Fatty acid bile acid conjugates (FABAC) are new molecules for improving cholesterol solubilization and preventing cholesterol crystallization in bile. A series of novel FABAC molecules were prepared by conjugation of the carboxyl group of cholic acid or ursodeoxycholic acid with saturated fatty acids of variable chain length using two amide bonds and amino acid as linkers, and the structures of them were confirmed by element analysis, IR, 1H NMR and MS techniques. The fatty acid bile acid conjugates activity of dissolving cholesterol crystallization was tested in model bile, and the activity of preventing of biliary cholesterol crys-tallization in vivo was tested in inbred mice.

Key words: cholesterol crystallization, bile acid, fatty acid bile acid conjugate, gallstone