Method for preparing sitafloxacin
A technology for sitafloxacin and compound, which is applied in the field of preparation of sitafloxacin, can solve the problems of many impurities, low yield, complicated post-processing and the like, and achieves the effects of high yield, reduced reaction rate and easy operation.
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
Embodiment 1
[0031] Dissolve 50.0 g of compound II and 40.0 g of compound III in 600 ml of acetonitrile, add 20.5 g of triethylamine, raise the temperature to 80° C., and react for 2 hours. TLC detects that the reaction is complete. Cool down to 0°C, stir for 2 hours, then filter with suction, and dry the filter cake with hot air at 45°C for 6 hours to obtain 70.2 g of pale yellow product IV. Yield: 87.4%.
[0032] Dissolve 50.0g of compound IV in 500ml of dichloromethane, and drop it into 250ml of 37% concentrated hydrochloric acid that has been cooled to 0°C in advance. During the dropwise addition, the temperature was controlled at 0°C to 5°C. After dropping, the temperature was raised to 20°C to 30°C for 1 hour. After the reaction is complete. Separate the water layer, adjust the pH value to 6∼7 with 20% sodium hydroxide, then adjust the pH value to 9∼10 with 28% concentrated ammonia water, concentrate under reduced pressure at room temperature to remove ammonia, and suction filter ...
Embodiment 2
[0035] Dissolve 100.0 g of compound II and 80.0 g of compound III in 1200 ml of acetonitrile, add 41.0 g of triethylamine, raise the temperature to 80° C., and react for 2 hours. TLC detects that the reaction is complete. Cool down to 0°C, stir for 2 hours, then filter with suction, and dry the filter cake with hot air at 45°C for 6 hours to obtain 143.0 g of pale yellow product IV. Yield: 89.0%.
[0036] 100.0g of compound IV was dissolved in 2000ml of ethyl acetate, and dropped into 1000ml of 37% concentrated hydrochloric acid which had been cooled to 0°C in advance. During the dropwise addition, the temperature was controlled at 0°C to 5°C. After dropping, the temperature was raised to 20°C to 30°C for 1 hour. After the reaction is complete. Separate the water layer, adjust the pH value to 2∼3 with 15% sodium hydroxide, then adjust the pH value to 9∼10 with 28% concentrated ammonia water, concentrate under reduced pressure at room temperature to remove ammonia, and sucti...
Embodiment 3
[0039] Dissolve 100.0 g of II and 80.0 g of III in 2000 ml of acetonitrile, add 41.0 g of triethylamine, raise the temperature to 80°C, and react for 2 hours. TLC detects that the reaction is complete. Cool down to 0°C, stir for 2 hours, then filter with suction, and dry the filter cake with hot air at 45°C for 6 hours to obtain 147.0 g of pale yellow product IV. Yield: 91.5%.
[0040] 100.0 g of compound IV was dissolved in 1600 ml of methyl acetate, and dropped into 800 ml of 37% concentrated hydrochloric acid that had been cooled to 0°C in advance. During the dropwise addition, the temperature was controlled at 0°C to 5°C. After dropping, the temperature was raised to 20°C to 30°C for 1 hour. After the reaction is complete. Separate the water layer, adjust the pH value to 6∼7 with 10% potassium hydroxide, then adjust the pH value to 10∼11 with 28% concentrated ammonia water, concentrate under reduced pressure at room temperature to remove ammonia gas, and suction filter ...
PUM
Abstract
Description
Claims
Application Information
- R&D Engineer
- R&D Manager
- IP Professional
- Industry Leading Data Capabilities
- Powerful AI technology
- Patent DNA Extraction
Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.
© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com