172548-92-4 2,3,4,5-Tetradehydroprolyl-allothreonyl-seryl-3-phenyl-beta-alanyl-L-allothreonine methyl ester Asterinin E L-Allothreonine, N-(N-(N-(N-(2,3,4,5-tetradehydroprolyl)-L-allothreonyl)-L-seryl)-(R)-3-phenyl-beta-alanyl)-, methyl ester delta(2,4)-Pro-L-allo-thr-L-ser-L-betahe-L-allo-throme delta(2,4)-Pro-allo-thr-ser-betaphe-allo-throme