Dicyclohexylcarbodiimide → 3(R)-[3-cyclopentanone-1(R)-carboxamido]-4-oxo-2(S)-phenyl-2,3,4,5-tetrahydro-1,5-benzothiazepine-5-acetamide

Participants

Reaction Steps

To a solution of 10 ml of dry dimethylformamide of 511 mg of ethyl 3(R)-amino-4-oxo-2(S)-phenyl-2,3,4,5-tetrahydro-1,5-benzothiazepine-5-acetate, 200 mg of 3-cyclopentanone-1(R)-carboxylic acid which is prepared according to the known procedure and 322 mg of 1-hydroxybenzotriazole is added 322 mg of dicyclohexylcarbodiimide. After allowing to stand overnight, the precipitated dicyclohexylurea is filtered off. The dimethylformamide was distilled off under reduced pressure, and to the residue is added chloroform. After washing with an aqueous solution of sodium chloride and drying over magnesium sulfate, the solvent is distilled off. The residue is subjected to column chromatography on silica gel and crystallized from benzene to give 540 ml of 3(R)-[3-cyclopentanone-1(R)-carboxamido]-4-oxo-2(S)-phenyl-2,3,4,5-tetrahydro-1,5-benzothiazepine-5-acetamide, m.p.=135°- 150° C.

Provenance & Evidence