A Concise Synthesis of α-Amino Acid N-Carboxy Anhydrides of (2S,3S)-β-Substituted Serines.

A general access to 3-hydroxy-4-(1-hydroxyalkyl)--lactams with a C4-C1 relative configuration unlike is provided. The subsequent oxidative ring expansion of the corresponding 3-hydroxy -lactam smoothly affords an -amino acid N-carboxy anhydride (NCA) formally derived from (2S,3S)--substituted serine, which upon sequential peptide coupling furnishes the tripeptide segment 2, present in lysobactin. © 2001 Elsevier Science Ltd. All rights reserved.