Sitafloxacin and its related substance D-2 were obtained with a total product yield of 78.7%.The structures of Sitafloxacin and intermediates from the step reactions were confirmed using MS, HNMR and TG.The optimal conditions for each step reaction were as following: in the debenzylation reaction, 10% of Pd/C with a reflux time of 0.5 h was adopted; in the post-treatment of condensation reaction, a mixed solvent of water and acetonitrile with a volume ratio of 2:1 was used; in the deprotection of N-boc reaction, the amount of hydrochloric acid was 15 times of the substrate in mole.
