With the rapid development and complex challenges of chemical substances, new drug synthesis pathways are usually the most effective.112984-60-8,6-Fluoro-1-methyl-4-oxo-7-(piperazin-1-yl)-1,4-dihydro-[1,3]thiazeto[3,2-a]quinoline-3-carboxylic acid,as a common compound, the synthetic route is as follows.
Example 1 Preparation of (S)-(-)-uliflourxacin; 105 g of racemic uliflourxacin was dissolved in 1,500 mL of dimethyl sulfoxide. 27 g of D-tartaric acid was dissolved in 405 mL of dimethyl sulfoxide dropwise while stirring. After stirring at room temperature for 20 hours, the precipitate was filtrated. The collected solid was dried under vacuum to obtain 86 g solid, which was recrystallized in dimethyl sulfoxide to obtain 37 g of levoulifloxacin-D-tartrate, with C49.08%, H5.06%, N9.50%, S7.44% shown by elemental analysis (molecular formula: C16H16FN3O3S·1/2C4H6O6·H2O, calculated values: C48.86%, H4.78, N9.50%, S7.25%). Said salt was added into water to obtain a suspension, and the pH value was adjusted to 7-8 with 2% NaOH aqueous solution while stirring. After precipitation, filtration, and drying, 24.5 g of (S)-uliflourxacin was obtained, having a chemical name (S)-(-)-6-fluoro-1-methyl-4-oxo-(1-piperazinyl)-1H,4H-[1,3]thiazeto [3,2-alpha]quinoline-3-carboxylic acid. Specific rotation [alpha]20D= -133 (c=0.5, 0.1 mol/L methanesulfonic acid); 1H-NMR (DMSO-d6) delta2.11 (3H, d, j=6.2 Hz), 2.87 (4H, m), 3.19 (4H, m), 6.40 (1H, q, j=6.2 Hz), 6.89 (1H, d, j=7.4Hz), 7.79 (1H, d, j=13.9Hz), optical purity e.e. 96%.
112984-60-8, 112984-60-8 6-Fluoro-1-methyl-4-oxo-7-(piperazin-1-yl)-1,4-dihydro-[1,3]thiazeto[3,2-a]quinoline-3-carboxylic acid 124225, apiperazines compound, is more and more widely used in various fields.
Reference：
Patent; Hainan Hualon Pharmaceutical Co., Ltd.; EP2524922; (2012); A1;,
Piperazine – Wikipedia
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