Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Chemical preparation method of norfloxacin

A norfloxacin and chemical technology, applied in the field of chemical preparation of norfloxacin, can solve the problems of poor selectivity, no economic value, low product conversion rate and the like

Active Publication Date: 2011-11-16
ZHEJIANG GUOBANG PHARMA
View PDF3 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0020] Although this method solves the selectivity problem, the price of trifluoroacetic anhydride is expensive, which is higher than that of norfloxacin, so this method has no economic value in the end.
[0021] The direct reduction of piperazine has poor selectivity due to the competition of the 6-position fluorine in the reaction, so the conversion rate of the final product is not high. Although the chelation process solves the problem of reaction selectivity, it increases the production due to the use of more auxiliary reagents. Finished product, also not economical from an atomic utilization point of view

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Chemical preparation method of norfloxacin
  • Chemical preparation method of norfloxacin
  • Chemical preparation method of norfloxacin

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0033] Example 1 , drop into 30g (0.111mol) 1-ethyl-6-fluoro-7-chloro-4-oxo-1,4-dihydro-quinoline-3-carboxylic acid, 60g piperazine (0.697mol) in four-necked flask mol), 75g of isoamyl alcohol, 1.5g of aluminum trichloride (0.0112mol), heated to 100 ° C for 12 hours, then added 4.5g of sodium hydroxide (0.113mol), recovered to dryness under reduced pressure, and added to the residue 150g water, 4.5g sodium hydroxide (0.113mol), 0.1g activated carbon, heat up to 90°C for 30 minutes, filter, adjust the pH of the obtained filtrate to neutral, cool to room temperature and suction filter, and dry the filter cake at 100°C 31.6 g of the product was obtained, and the liquid phase detection content was 99.5%, of which the content of the 6-position fluorine-substituted isomer was 0.1%. Yield 88.9%.

[0034] Example 2 , drop into 30g (0.111mol) 1-ethyl-6-fluoro-7-chloro-4-oxo-1,4-dihydro-quinoline-3-carboxylic acid, 27g piperazine (0.313 mol), 13g methanol, 30g aluminum trichloride...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention mainly discloses a chemical preparation method of norfloxacin. The chemical preparation method is performed by carrying out reaction on 1-ethyl-6-fluoro-7-chloro-4-oxo-1,4-dihydro-quinoline-3-carboxylic acid (formula I) and piperazine (formula II) used as raw materials, Lewis acid used as a catalyst and alcohol used as a solvent at a certain temperature for a certain period of time, and then carrying out post-treatment to obtain norfloxacin. The chemical preparation method disclosed by the invention has the advantages of mild reaction conditions, high reaction selectivity, and extremely low ratio of a 6-fluoro-substituted isomer, and is a very competitive synthesis route.

Description

technical field [0001] The invention relates to a chemical preparation method of norfloxacin. Background technique [0002] Norfloxacin is widely used as an anti-infective drug, and has the advantages of strong antibacterial activity, broad antibacterial spectrum, high bioavailability, good tissue penetration, no cross-resistance with other antibiotics, and small side effects. Its synthetic method has many reports, and its core step is the substitution reaction of piperazine and quinoline carboxylic acid. [0003] [0004] The synthetic routes suitable for industrial production are mainly divided into two categories: direct piper shrinkage and chelation piper shrinkage. [0005] 1. Direct shrinkage method: [0006] (1) Indian, 178696, 07 Jun 1997. In this method, pyridine is used as a solvent, reacted at 115°C, and carboxylic acid is directly reacted with piperazine to obtain norfloxacin. [0007] However, pyridine pollutes the environment greatly, has an unpleasant...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): C07D215/56
Inventor 邱家军刘聪姚礼高林军舒龙单国洋周志奎
Owner ZHEJIANG GUOBANG PHARMA
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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