7H-Pyrido[1,2,3-de]-1,4-benzoxazine-6-carboxylic acid, 9,10-difluoro-2,3-dihydro-3-methyl-7-oxo-, ethyl ester, (3S)-
7H-Pyrido[1,2,3-de]-1,4-benzoxazine-6-carboxylic acid, 9,10-difluoro-2,3-dihydro-3-methyl-7-oxo-, ethyl ester, (S)-
Ethyl (3S)-9,10-difluoro-2,3-dihydro-3-methyl-7-oxo-7H-pyrido[1,2,3-de]-1,4-benzoxazine-6-carboxylate
Ethyl 9,10-difluoro-3-(S)-methyl-7-oxo-2,3-dihydro-7H-pyrido[1,2,3-de]-1,4-benzoxazine-6-carboxylate