Ala Ud Din
Bacha Khan University
Ochrine Aand B were isolated from the culture broth of Hawaiian marine sedimentderived-fungus Aspergillus ochraceopetaliformis (088702A) after impressive cytotoxic data of its crude extract. The structuresof these compounds were found to be new cyclotetrapeptides; cyclo[-L-lle-L-Thr-L-O-Me-Tyr-L-pro-] for Ochrine Aand cyclo[-L-lle-L-Thr-L-OMe- Tyr-L-N-Me-Ala-] for Ochrine B. The sequence and absolute configurations of amino acids were determined by ESI-TOPMS, NMR and Marfey’s analysis.