Check patentability & draft patents in minutes with Patsnap Eureka AI!

Preparation method of pyrazolopyridine derivative

A technology of pyrazolopyridine and derivatives, which is applied in the field of new preparation of pharmaceutical intermediates, and can solve problems such as difficulties in pyridine synthesis

Inactive Publication Date: 2015-04-29
湖南华腾制药有限公司
View PDF2 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The synthesis of 3-(chloromethyl)-1H-pyrazolo[3,4-b]pyridine is difficult at present

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 pyrazolopyridine derivative
  • Preparation method of pyrazolopyridine derivative
  • Preparation method of pyrazolopyridine derivative

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0020] (1) Synthesis of 3-acetyl-2-chloropyridine

[0021] Add 22g of 2-chloro-3-cyanopyridine to 120°C of anhydrous tetrahydrofuran, add 120ml of 1M methylmagnesium iodide, heat and reflux and stir for 3 hours, cool, add water and ethyl acetate, extract and separate, and collect organic phase, dried and concentrated to obtain 27 g of 3-acetyl-2-chloropyridine.

[0022] (2) Synthesis of 3-methyl-1H-pyrazolo[3,4-b]pyridine

[0023] Add 27g of 3-acetyl-2-chloropyridine to 280ml of absolute ethanol, add 100ml of hydrazine hydrate, heat and stir for 12 hours, cool, add water and ethyl acetate for extraction and separation, collect the organic phase, dry, concentrate, pass Column separation gave 21 g of 3-methyl-1H-pyrazolo[3,4-b]pyridine.

[0024] (3) Synthesis of 3-(chloromethyl)-1H-pyrazolo[3,4-b]pyridine

[0025] Add 20g of 3-methyl-1H-pyrazolo[3,4-b]pyridine to 180ml of dichloromethane, add 41g of N-chlorosuccinimide, stir at room temperature for 2 hours, add water, extract...

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 a pyrazolopyridine derivative 3-(chloromethyl)-1H-pyrazolo[3,4-b]pyridine. 2-chloro-3-cyanopyridine is used as a start raw material, and the target product is obtained through a Grignard reaction, ring closing and chlorine addition. The compound is an important medical intermediate.

Description

technical field [0001] The invention relates to a novel preparation method of a pharmaceutical intermediate, in particular to a preparation method of a pyrazolopyridine derivative 3-(chloromethyl)-1H-pyrazolo[3,4-b]pyridine. technical background [0002] Compound 3-(chloromethyl)-1H-pyrazolo[3,4-b]pyridine, the structural formula is: [0003] [0004] The compound 3-(chloromethyl)-1H-pyrazolo[3,4-b]pyridine and related derivatives are widely used in medicinal chemistry and organic synthesis. Currently, the synthesis of 3-(chloromethyl)-1H-pyrazolo[3,4-b]pyridine is difficult. Therefore, it is necessary to develop a synthetic method with easy-to-obtain raw materials, convenient operation, easy-to-control reaction and suitable overall yield. Contents of the invention [0005] The invention discloses a preparation method of pyrazolopyridine derivative 3-(chloromethyl)-1H-pyrazolo[3,4-b]pyridine, starting with 2-chloro-3-cyanopyridine Raw materials, through Grignard reac...

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): C07D471/04
CPCC07D471/04
Inventor 不公告发明人
Owner 湖南华腾制药有限公司
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