Acetic Acid → 5-t-butoxycarbonylmethyl-3-(1-ethoxycarbonylethylamino)-2,3-dihydro-1,5-benzothiazepin-4(5H)-one

Participants

Reaction Steps

1.5 g of 3-amino-5-t-butoxycarbonylmethyl-2,3-dihydro-1,5-benzothiazepin-4(5H)-one and 2.0 g of ethyl pyruvate were dissolved in 15 ml of ethanol. After the addition of 0.3 ml of acetic acid, the resulting mixture was stirred for 2 hours. Then, a solution of 420 mg of sodium boron cyanide hydride in 8 ml of ethanol was slowly added dropwise thereto. After this mixture was allowed to stand overnight, the solvent was distilled off under reduced pressure and the residue was dissolved in ethyl acetate. The resulting solution was washed with water, dried and then concentrated. The residue was purified by silica gel column chromatography using a 3:1 mixture of benzene and ethyl acetate as the eluent. Thus, there was obtained 1.0 g of the desired compound in the form of an oily material.

Provenance & Evidence