A facile synthesis of bestatin.

Abstract
Bestatin, an immunomodulator useful in cancer treatment with the structure N-[(2S,3R)-3-amino-2-hydroxy-4-phenylbutanoyl]-L-leucine was synthesized from N-acyl-.alpha.-aminoacetophenone. This novel method using readily available reagents and mild conditions can be applied to a large scale production of this useful agent. The overall yield of bestatin was 10.5% from N-acetyl-.alpha.-aminoacetophenone and 7.8% from N-benzoyl-.alpha.-aminoacetophenone.