Synthesis and Biological Activities of Cyclic Peptide, Hymenamide Analogs

摘要

A great variety of useful bioactive peptides have been isolated from various natural sources and those structures also determined. Especially, cyclic peptides have been well found as bioactive components, they were expected as seed compounds in drug design due to their metabolic stabilities and restricted conformations. Hymenamides were one class of these cyclic peptides isolated from Okinawan marine sponge Hymeniacidon sp. [1-4]. So far, ten peptides have been isolated. Composed of few amino acid residues, they have exhibited antifungal, cytotoxic and enzyme inhibiting activities. Napolitano et al. reported inhibition of human neutrophil elastase release by Hymenamide C [5]. Since excess releases of elastase cause the chronic obstructive pulmonary disease (COPD), hymenamides have been expected as the useful proto-type therapeutic tools for COPD. The development of effective syntheses of analogs and further structural-activity relationship studies are necessary for the practical usage of hymenamides in drug discovery.