Feb-Маг 1991 Asymmetric Reduction of 7,8-Difluoro-3-methyl-2#-l,4-benzoxazine. Synthesis of a Key Intermediate of (5)-(-)-0floxacin (DR-3355) Shohgo Atarashi*, Hideaki Tsurumi, Toshihiro Fujiwara and Isao Hayakawa Research Institute, Daiichi Pharmaceutical Co., Ltd., 1-16-13, Kitakasai, Edogawaku, Tokyo 134, Japan Received July 18, 1990 An efficient, highly enantioselective synthesis of (S)-(-)-7,8-difluoro-2,3-dihydro-3-methyl-4#-l,4-ben- zoxazine, a key ...