摘要:
Starting with the proteinogenic amino acid (S)-glutamate (3) a facile, high yielding synthesis of the chiral non-racemic 3-(dioxo-piperazin-2-yl)propionates 6, 11, and 14 is presented. Key intermediates in the synthesis of Ne-benzyl substituted (dioxopiperazin-2-yl)propionates 11 and 14 are the N-monobenzylglutamate 8 and the chloroacetamide 12, which allow introduction of various substituents in position 4 of the piperazine ring. In receptor binding studies with radioligands the 3-(piperazin-2-yl)propanol 15 was found to have promising affinity for sigma(1)-receptors (K-i=66.1 nM). (C) 2002 Elsevier Science Ltd. All rights reserved.