Preparation method of 6-bromo-3-hydroxy-2-pyrazinecarboxamide

A technology of pyrazine carboxamide and carbamoyl pyrazine, which is applied in the field of preparation of 6-bromo-3-hydroxy-2-pyrazine carboxamide, can solve the problems of idle instruments, reduced production efficiency, and low conversion rate of raw materials, and achieves The effect of cleaning the reaction route, simplifying the production operation and shortening the reaction time

Pending Publication Date: 2021-08-10
河北唯达生物医药产业技术研究有限公司
View PDF2 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

It is currently known that 6-bromo-3-hydroxyl-2-pyrazinamide is the main raw material used to prepare 6-fluoro-3-hydroxyl-2-pyrazinamide, and the patent with the authorized announcement number of CN 102307865B proposes a The preparation method of chloropyrazine derivatives, and the synthetic method of 6-bromo-3-hydroxypyrazine-2-carboxamide is provided, in the cooling 2-aminomalonic acid diamide sodium hydroxide aqueous solution, drop ethylene di Aldehyde solution, stirring repeatedly to obtain 2-carbamoylpyrazine-3-hydroxyl sodium, then suspending 2-carbamoylpyrazine-3-hydroxyl sodium in a mixture of methanol and acetonitrile or ethyl acetate, and Add bromine dropwise and stir to filter out the solid product to obtain 6-bromo-3-hydroxypyrazine-2-carboxamide. Another example is the patent of CN11197

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 6-bromo-3-hydroxy-2-pyrazinecarboxamide

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0022] 1) Add methanol (160kg) and acetonitrile (600kg) to the reactor, stir and add 2-carbamoylpyrazine-3-hydroxysodium (161kg) and tetrabutylammonium bromide (16kg);

[0023] 2) Control the temperature of the system at 30-35°C, and slowly add liquid bromine to the system dropwise. After the dropwise addition, control the temperature of the system at 30-35°C, and stir for 4 hours. The bromine color of the reaction system will fade away. Use TLC to spot the reaction. whether it is completed;

[0024] 3) After the reaction is completed, cool the reaction solution to 0-10°C, and slowly add cooling water dropwise;

[0025] 4) After adding the cooling water dropwise, continue to stir and crystallize at 0-10°C for 2 hours, centrifuge, rinse with an appropriate amount of drinking water during the centrifugation process, and obtain a light yellow solid wet product;

[0026] 5) The wet product was air-dried at 70-80° C., and collected to obtain 181 kg of light yellow solid, with a yi...

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 method for preparing 6-bromine-3-hydroxyl-2-pyrazinecarboxamide by using 2-carbamoyl pyrazine-3-sodium hydroxide, and belongs to the field of chemical engineering. The method comprises the following steps: dissolving 2-carbamoyl pyrazine-3-sodium hydroxide and a catalyst in a solvent, dropwise adding a bromine reagent, performing stirring to react to generate 6-bromine-3-hydroxyl-2-pyrazinecarboxamide, performing stirring and crystallizing in ice water, and performing filtering to obtain a pure product of 6-bromo-3-hydroxyl-2-pyrazinecarboxamide. Compared with a traditional method, the method for dropwise adding bromine water has the advantages that the reaction time is greatly shortened, the production operation is simplified, the production efficiency is improved, the whole reaction route is clean and environment-friendly, and the method is suitable for industrial production.

Description

technical field [0001] The invention relates to the field of chemical industry, in particular to a preparation method of 6-bromo-3-hydroxy-2-pyrazine carboxamide. Background technique [0002] 6-Fluoro-3-hydroxy-2-pyrazinecarboxamide is a compound used for preventing and treating viral infectious diseases, especially influenza virus infectious diseases. It is currently known that 6-bromo-3-hydroxyl-2-pyrazinamide is the main raw material used to prepare 6-fluoro-3-hydroxyl-2-pyrazinamide, and the patent with the authorized announcement number of CN 102307865B proposes a The preparation method of chloropyrazine derivatives, and the synthetic method of 6-bromo-3-hydroxypyrazine-2-carboxamide is provided, in the cooling 2-aminomalonic acid diamide sodium hydroxide aqueous solution, drop ethylene di Aldehyde solution, stirring repeatedly to obtain 2-carbamoylpyrazine-3-hydroxyl sodium, then suspending 2-carbamoylpyrazine-3-hydroxyl sodium in a mixture of methanol and acetonitri...

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): C07D241/24
CPCC07D241/24
Inventor 瞿鑫马良
Owner 河北唯达生物医药产业技术研究有限公司
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap