名称:
Efficient and stereoselective synthesis of (2S,3S,4S)-3,4-dihydroxyglutamic acid via intramolecular epoxidation
摘要:
The stereoselective synthesis of bioactive (2S,3S,4S)-3,4-dihydroxyglutamic acid hydrochloride salt was achieved. The key step involved an intramolecular nucleophilic epoxidation of homochiral gamma-amino- alpha,beta-unsaturated ester 5 containing an N-hydroperoxymethyl group followed by regioselective opening of the resulting epoxide with neighboring group participation of the N-Boc group. The diastereoselectivity was more than 20:1 by H-1 NMR spectroscopy. Thus, (2S,3S,4S)-3,4-dihydroxyglutamic acid hydrochloride salt was prepared from configurationally stable N-BOC-D-Serinal 4 in 25% overall yield over nine steps. (C) 2008 Elsevier Ltd. All rights reserved.