摘要:
Four diastereomers, (2R 3R), (2S 3S), (2S,3R) and (2R,3S) at beta-methoxytyrosine (beta-OMeTyr), of the tripeptide hydrolysate, H-(S)-N-MeThr-beta-OMeTyr-(S)-Hpr-OH, from papuamide A have been synthesized. Comparison of the H-1 NMR data of the natural hydrolysate with the four synthetic diastereomers unambiguously establishes the relative and absolute stereochemistry of the methoxytyrosine as 2R,3R. (c) 2005 Elsevier Ltd. All rights reserved.