2-(r)-fluorosulfonyloxy-4-phenylbutiric acid esters, production process and process for its utilization in the preparation of carboxyalkyldipeptides

摘要

2-(R)-fluorosulfonyloxy-4-phenylbutiric acid esters have the formula (I) wherein R1 is benzyl or alkyl C1-C6 and are obtained by the reaction of 2-(R)-hydroxy-4-phenylbutiric acid esters with fluorosulfonic anhydride in the presence of an organic base. They are used in the preparation of carboxyalkyldipeptides having the formula (II) wherein R1 is C1-C6 alkyl or hydrogen; R2 is methyl or -(CH2)4-NH2; R3 is hydrogen.