Anti-inflammatory cyclopeptides from the marine sponge Theonella swinhoei

DCCC chromatography followed by HPLC purification on the polar extract of marine sponge Theonella swinhoei resulted in the isolation of five new cyclopeptides, perthamides G-K. The new structures, featuring unprecedented amino acid units, were determined by interpretation of extensive spectroscopic and spectrometric data (MS, H-1 and C-13 NMR, COSY, HSQC, HMBC, and ROESY). Pharmacological analysis demonstrated that these natural cyclopeptides are endowed with anti-inflammatory potential as assessed by their ability to reduce carrageenan-induced mouse paw oedema. (C) 2012 Elsevier Ltd. All rights reserved.