Anti-inflammatory Amino Acid Derivatives from the Ascidian Herdmania momus

Four new amino acid derivatives, herdmanines A-D (1-4), were isolated from the marine ascidian Herdmania momus. Herdmanines A-C contain the unusual D-form of arginine. Compounds 3 and 4 had a moderate suppressive effect on the production of NO, with IC50 values of 96 and 9 mu M, respectively. These compounds were found to inhibit the mRNA expression of iNOS. The inhibitory activities on the production and mRNA expression of pro-inflammatory cytokines such as TNF-alpha, IL-1 beta, and IL-6 were evaluated.