Synthetic and pharmacological studies on Longicalycinin A

Present investigation describes the synthesis of a natural phenylalanine-rich cyclopolypeptide longicalycinin A (10) by coupling of dipeptide unit Boc-L-phe-L-tyr-OH with tripeptide unit L-pro-L-phe-gly-OMe followed by cyclization of linear segment. Synthesized cyclic pentapeptide was characterized by spectral techniques including FTIR, 1H/13C NMR, FAB MS and elemental analysis and screened for different pharmacological activities.