Eureka AIR delivers breakthrough ideas for toughest innovation challenges, trusted by R&D personnel around the world.

Method for preparing letrozole impurity

A kind of technology of letrozole impurity and impurity, applied in the field of medicinal chemistry

Inactive Publication Date: 2013-08-14
HARBIN PHARMA GRP CO LTD GENERAL PHARMA FACTORY
View PDF2 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0007] At present, there is no report on the preparation method of letrozole impurity in China

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
  • Method for preparing letrozole impurity
  • Method for preparing letrozole impurity
  • Method for preparing letrozole impurity

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0023] Example 1: Step 1: Dissolve 10g of letrozole in 50ml of acetone, add 100ml of water, add 30% NaOH solution, adjust pH=10.5, liquid phase detection until the main peak disappears, the impurity C peak area percentage is 58% ;

[0024] Step 2: evaporate the acetone under reduced pressure, filter the resulting suspension to obtain a crude impurity product with a purity of 81%;

[0025] Step 3: Recrystallize the obtained impurity crude product in ethanol to obtain impurity C, about 4.9 g, with a yield of 49% and a purity of over 99%.

Embodiment 2

[0026] Example 2: Step 1: Dissolve 20g of letrozole in 100ml of acetone, add 200ml of water, add 30% sodium carbonate solution, adjust pH=11.2, liquid phase detection until the main peak disappears, impurity C peak area percentage 63 %;

[0027] Step 2: evaporate the acetone under reduced pressure, filter the resulting suspension to obtain a crude impurity product with a purity of 80%;

[0028] Step 3: Recrystallize the obtained impurity crude product in ethanol to obtain impurity C, about 10 g, with a yield of 50% and a purity of more than 99%.

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 relates to a method for preparing a letrozole impurity. A reference substance is provided for quantitative and qualitative analysis of letrozole impurity detection by synthesizing the letrozole impurity. Thus, the quality standard of letrozole is improved; guidance is provided for safe medication of letrozole; and meanwhile, an effective detection foundation is provided for obtaining the letrozole drug which accords with the quality standard of USP (United States Pharmacopoeia).

Description

technical field [0001] The invention belongs to the field of medicinal chemistry, and more specifically relates to a method for preparing impurity C in the preparation process of letrozole. [0002] [0003] Background technique: [0004] Letrozole, Chinese alias: 1-[bis(4-cyanophenyl)methyl]-1,2,4-triazole; 4,4'-(1 H-1,2,4-triazole -1-ylmethylene)-bisbenzonitrile. [0005] Letrozole is a new generation of aromatase inhibitors. It is a synthetic benzyltriazole derivative. Letrozole reduces the level of estrogen by inhibiting aromatase, thereby eliminating the stimulating effect of estrogen on tumor growth. In vivo and in vitro studies have shown that letrozole can effectively inhibit the transformation of androgen into estrogen, and estrogen in postmenopausal women mainly comes from the aromatization of androgen precursors in peripheral tissues, so it is especially suitable for postmenopausal breast cancer patient. The in vivo activity of letrozole is 150-250 ti...

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): C07C255/56C07C253/30
Inventor 孙志嘉王硕冰王志强
Owner HARBIN PHARMA GRP CO LTD GENERAL PHARMA FACTORY
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
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