Studies on Peptides. IV. The Synthesis of D-Histidyl-L-phenylalanyl-L-arginyl-L-tryptophylglycine and L-Histidyl-L-phenylalanyl-L-arginyl-D-tryptophylglycine and Their Physiological Properties in Frog melanocyte in vitro

Abstract

The synthesis of two steroisomeric pentapeptides, D-histidyl-L-phenylalanyl-L-arginyl-L-tryptophylglycine and L-histidyl-L-phenylalanyl-L-arginyl-D-tryptophylglycine was described and their melanocyte-expanding activities have been assayed in vitro. It was observed that D-histidyl-L-phenylalanyl-L-arginyl-L-tryptophylglycine is biologically inert while L-histidyl-L-phenylalanyl-L-arginyl-D-tryptophylglycine possesses 1×10⁵ MSH U/g.