Title:
METHOD FOR REFINING BENZHEXOL HYDROCHLORIDE
Document Type and Number:
WIPO Patent Application WO/2021/212535
Kind Code:
A1
Abstract:
Provided is a method for refining benzhexol hydrochloride, the method comprising the following steps: step one, adding a benzhexol hydrochloride crude product into purified water and stirring the mixture uniformly; adjusting the pH value of the mixture with an alkaline solution, and then maintaining the temperature, and filtering and washing same, and then collecting a filter cake; step two, adding the filter cake obtained in step one into purified water and stirring the mixture uniformly; adjusting the pH value of the mixture to be between 2 and 3 with a hydrochloric acid solution, and de-coloring same with active carbon and filtering same; adjusting the pH value with a hydrochloric acid solution to form a salt, and then heating same and maintaining the temperature; and cooling and crystallizing, filtering, washing, and drying same under reduced pressure to obtain a benzhexol hydrochloride pure product. By means of using an alkaline washing and acid adjusting method, the benzhexol hydrochloride pure product with a high yield and high purity can be obtained, so that a method for refining benzhexol hydrochloride by means of recrystallization via an organic solvent in the prior art is replaced. Not only does the obtained refined product have a good appearance, a high yield and no organic solvent residues, and the product meets the requirements of pharmaceutical standards, but also the process is simple to operate and is cost saving, thus facilitating industrial production.
Inventors:
LIANG ZHIXIANG (CN)
ZHU ZHANYUAN (CN)
LIU WENJIE (CN)
LIU WENLI (CN)
KONG KAILI (CN)
ZHU ZHANYUAN (CN)
LIU WENJIE (CN)
LIU WENLI (CN)
KONG KAILI (CN)
Application Number:
PCT/CN2020/087368
Publication Date:
October 28, 2021
Filing Date:
April 28, 2020
Export Citation:
Assignee:
JIANGSU TASLYDIYI PHARMACEUTICAL CO LTD (CN)
International Classes:
C07D211/94; C07C209/82; C07C209/84; C07C209/86; C07D295/092
Foreign References:
| CN105218481A | 2016-01-06 | |||
| CN106518689A | 2017-03-22 | |||
| CN110960577A | 2020-04-07 | |||
| CN1233612A | 1999-11-03 | |||
| US3758580A | 1973-09-11 |
Other References:
"Chemistry of Chinese Materia Medica", 31 December 2011, HUNAN SCIENCE AND TECHNOLOGY PRESS, CN, ISBN: 978-7-5357-6993-0, article DOU, DEQIANG CHIEF EDITOR: "2. Alkaloid Salts", pages: 40, XP009531507
Attorney, Agent or Firm:
HUAIAN KEWEN INTELLECTUAL PROPERTY OFFICE (CN)
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