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Moxifloxacin, one of newly marketed fluoroquinolones drugs, is an antimicrobial compound useful as a medicament for humans, animals, and fishes and an antimicrobial agent containing the same. (s, s)-6-Benzyloctahydropurrolo[3,4-b]pyridine is an intermediate of moxifloxacin.A novel synthesis route was proposed based on literatures and comprehensive comparison, (s, s)-6-Benzyloctahydropurrolo[3,4-b]pyridine was synthesized with some improvements.First, the process comprising reacting the reaction product of pyridinedicarboxylic acid anhydride and benzylamine without solvent to give the intermediate 6-Benzyl-5,7-dihydro-5,7-dioxopyrrolo [3,4-b]pyridine.This intermediate was added THF and a palladium-on-carbon catalyst, and hydrogenation,was conducted under a pressurized hydrogen gas atmosphere at 85 ℃ and 8 kg/cm2 for 14 hours. The catalyst was removed by filtration, and the filtrate was concentrated, 6-Benzyl-5,7-dioxo-octahydropyrrolo[3,4-b]pyridine was obtained. This process is more economical.A method at atmospheic pressure was obtain to reduce oxo compound. In this process, Synhydrid, a new kind of reduced reagent, was used. A solution of 6-Benzyl-5,7-dioxo-octahydropyrrolo[3,4-b]pyridine in anhydrous THF was added dropwise to a solution of Synhydrid in anhydrous THF , then the mixture was stired for 10 hours in reflux conditions. The reaction was terminate by sodium hydroxide solution. The reaction mixture was filtrated and the filtrate was driedover anhydrous sodium sulfate and concentrated to produce. The research in this paper has not been reported in China and abroad.Then, (s, s)-6-Benzyloctahydropurrolo[3,4-b]pyridine was isolated from above reduce product with D-(-)-tartaric acid. The factor which impact this emperiment was reviewed, and the process was improved. Useing MS, IR, H1NMR, C13NMR, the product was identified.The overall yield is 55.5%, which is increased compared with the yield of literature method. Thus we succeed in getting an industrial route characterized by cheap and easily gained materials, convenient operate process and low cost.
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