左氧氟環合酯
化學名：(S)-9,10-二氟-3-甲基-7-氧代-2,3-二氫-7H-吡啶并[1,2,3-de]-1,4-駢惡嗪-6-羧酸乙酯
中文同義詞: 左旋環合酯;(S)-9,10-二氟-3-甲基-7-氧代-2,3-二氫-7H-吡啶并[1,2,3-de]-1,4-駢惡嗪-6-羧酸乙酯;左氧氟環合酯;左氧氟羧酸乙酯 
英文名稱: Ethyl (S)-9,10-difluoro-3-methyl-7-oxo-2,3-dihydro-7H-pyrido[1,2,3-de]-1,4-benzoxazine-6-carboxylate 
英文同義詞: 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)-;Levofloxacin carboxylic acid, ethyl ester;LEVOFLOXACINCYCLIZEDESTER;(3S)-9,10-Difluoro-2,3-dihydro-3-methyl-7-oxo-7H-pyrido[1,2,3-de]-1,4-benzoxazine-6-carboxylicacidethylester;ETHYL (S)-9,10-DIFLUORO-3-METHYL-7-OXO-2,3-DIHYDRO-7H-PYRIDO[1,2,3-DE]-1,4-BENZOXAZINE-6-CARBOXYLATE;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)-9,10-Difluoro-2,3-dihydro-3-methyl-7-oxo-7H-pyrido[1,2,3-de]-1,4-benzoxazine-6-carboxylic Acid Ethyl Ester;9,10-Difluoro-3-(S)-methyl-7-oxo-2,3-dihydro-7H-pyrido[1,2,3-de]-1,4-benzoxazine-6-carboxylate 
CAS號: 106939-34-8 
分子式: C15H13F2NO4 
分子量: 309.26 
用途：左氧氟環合酯是合成左藥物的一個主要原料。
性狀：類白色粉末 
比旋度[α]D20 - 64°～ - 72°（1% CH3COOH） 
熔點 256°C ～262°C 
干燥失重 ≤0.5% 
右旋異構體：≤0.3% 
有關物質 單一雜質≤0.5% 
甲酯雜質：≤0.5%
總雜質：≤1%
含量 ≥99% 
包裝：25KG 紙板桶