Supercharge Your Innovation With Domain-Expert AI Agents!

Preparation method of ethyl 2-amino-4-methylthiazole-5-carboxylate

A technology of methylthiazole and ethyl formate is applied in the field of preparation of 5-thiazole amide pharmaceutical intermediates, which can solve the problems of high energy consumption, high reaction temperature, long reaction time and the like, and achieves lowering reaction temperature and shortening reaction time. time, and the effect of reducing energy consumption

Inactive Publication Date: 2014-03-26
SHANDONG HUIHAI PHARMA & CHEM
View PDF6 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] The technical problem to be solved by the present invention is to provide a method for preparing ethyl 2-amino-4-methylthiazole-5-carboxylate, which overcomes the common problems of long reaction time, high reaction temperature and high energy consumption in the prior art.

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
  • Preparation method of ethyl 2-amino-4-methylthiazole-5-carboxylate

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0031] Add 200ml of ethanol containing 25% ethyl acetate to the four-necked bottle, add 30.4g of thiourea, 1.5g of sodium carbonate, raise the temperature to 45°C, add 33g of ethyl 2-chloroacetoacetate dropwise, drop it in 20-30 minutes, and drop it Raise the temperature to 65°C and keep it warm for 5h, evaporate most of the solvent at normal pressure and cool to room temperature. Filter to remove unreacted thiourea, add the filtrate to 500ml of water, stir with 30% liquid caustic soda to adjust the pH to 9-10, stir for 0.5h, vacuum dry for 2h after suction filtration to obtain 36.7g of the product, the yield is 98.39%, mp: 172~173℃.

Embodiment 2

[0033] Add 200ml of ethanol containing 20% ​​ethyl acetate to the four-necked bottle, add 30.4g of thiourea, 0.5g of sodium carbonate, raise the temperature to 45°C, add 33g of ethyl 2-chloroacetoacetate dropwise, drop it in 20-30min, drop it off Raise the temperature to 70°C and keep it warm for 5h, steam off most of the solvent under normal pressure and cool to room temperature. Remove unreacted thiourea by filtration, add the filtrate to 500ml of water, stir and adjust the pH to 9-10 with 30% liquid alkali, stir for 0.5h, vacuum dry for 2h after suction filtration to obtain 36.6g of the product, yield 98.12%, mp: 172~173℃.

Embodiment 3

[0035] Add 200ml of ethanol containing 10% ethyl acetate to the four-necked bottle, add 30.4g of thiourea, 0.5g of sodium carbonate, raise the temperature to 45°C, add 33g of ethyl 2-chloroacetoacetate dropwise, drop it in 20-30min, drop it off Raise the temperature to 65°C and keep it warm for 5h, evaporate most of the solvent at normal pressure and cool to room temperature. Remove unreacted thiourea by filtration, add the filtrate to 500ml of water, stir and adjust the pH to 9-10 with 30% liquid alkali, stir for 0.5h, vacuum dry for 2h after suction filtration to obtain 36.6g of the product, yield 98.12%, mp: 172~173℃.

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 discloses a preparation method of ethyl 2-amino-4-methylthiazole-5-carboxylate, which comprises the following steps: 1) preparing an ethyl acetate solution with the mass fraction of 10-35% by using ethyl alcohol as a solvent, and adding thiourea and sodium carbonate into the solution, wherein the weight ratio of the sodium carbonate to ethyl 2-chloroacetoacetate used in the step 2 is 0.01-0.1; 2) increasing the temperature to 40-55 DEG C, dropwise adding ethyl 2-chloroacetoacetate, heating to 60-70 DEG C after dripping off, and performing thermal insulation for 5-5.5 hours; 3) distilling to remove most of the solvent, then cooling to the room temperature, and filtering; 4) adding the filtrate into water, adjusting the pH value to be 9-10 through caustic soda liquid, and stirring; 5) filtering, and drying in vacuum to obtain ethyl 2-amino-4-methylthiazole-5-carboxylate. The technology has the advantages that the reaction time is short, the reaction temperature is low, the product yield is more than 98%, and the mp (melting point) is 172-173 DEG C.

Description

technical field [0001] The invention relates to a preparation method for preparing 5-thiazole amide drug intermediates, more specifically a preparation method for ethyl 2-amino-4-methylthiazole-5-carboxylate. Background technique [0002] Ethyl 2-amino-4-methylthiazole-5-carboxylate is a kind of off-white powder, which is mainly used in the synthesis of 5-thiazole amide compounds or their pharmaceutically acceptable stereoisomers in antineoplastic drugs. [0003] The molecular structure of 2-aryl substituted amino-4-methylthiazole-5-carboxylate derivatives has a bi-aromatic planar aromatic ring structure, and has the basic pharmacophore structure skeleton of anti-HIV-1, which is compatible with HIV- 1 The binding pockets of the substrate binding site of reverse transcriptase (RT) match each other, which is expected to be used in the design of HIV-1 RT inhibitors. [0004] At present, domestic and foreign reports use ethyl 2-chloroacetoacetate and thiourea as raw materials, ...

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
IPC IPC(8): C07D277/56
CPCC07D277/56
Inventor 李保铃张忠政张世凤
Owner SHANDONG HUIHAI PHARMA & CHEM
Features
  • R&D
  • Intellectual Property
  • Life Sciences
  • Materials
  • Tech Scout
Why Patsnap Eureka
  • Unparalleled Data Quality
  • Higher Quality Content
  • 60% Fewer Hallucinations
Social media
Patsnap Eureka Blog
Learn More

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2025 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com