A convenient strategy was developed to prepare several B-difluoroamino
acids. As exemplified by the synthesis of 3,3-difluoro-L-homocysteine
, 3,3-difluoro-L-homoserine and 3,3-difluoro-L-methionine, the reactio
n sequence all started from L-isoascorbic acid. This approach holds po
tential to be extended to make other beta-difluorine-containing amino
acids. (C) 1998 Elsevier Science Ltd. All rights reserved.