Conformationally biased analogs of oxytocin

Abstract

Four diastereomeric analogs of oxytocin containing substituted phenylalanine in position 2 were synthesized. This modified phenylalanine side chain contained one methyl group attached to the beta-carbon and the second one at the 2' position of the aromatic ring. All analogs were found to be inhibitors of uterotonic activity of oxytocin with pA2 values ranging from 6.0 to 8.3; the most potent one (pA2 = 8.3) contained dimethylphenylalanine of the D-erythro configuration.