Synthesis and in vitro Cytotoxic Activity of a Natural Peptide of Plant Origin

Present work reports the first total synthesis of a phenylalanine and glycine-rich cyclopolypeptide podacycline B by coupling of tripeptide Boc-L-phe-gly-L-phe-OH and tetrapeptide L-ala-gly-L-thr-L-ile-OMe followed by cyclization of linear heptapeptide segment. The chemical structure of the compound was elucidated by FTIR, 1H NMR, 13C NMR, FAB MS spectral data and elemental analyses. The newly synthesized peptide was subjected to biological screening and found to possess high cytotoxicity against Dalton’s lymphoma ascites (DLA) and Ehrlich’s ascites carcinoma (EAC) cell lines with IC50 values of 13.2 and 15.5 μM, in addition to moderate anthelmintic activity against earthworms M. konkanensis, P. corethruses and Eudrilus sp. at a dose of 2 mg ml-1.