Title:
PURIFICATION METHOD FOR METFORMIN HYDROCHLORIDE, METFORMIN HYDROCHLORIDE SUSTAINED RELEASE TABLET AND PREPARATION METHOD THEREFOR
Document Type and Number:
WIPO Patent Application WO/2022/148053
Kind Code:
A1
Abstract:
The present invention relates to the technical field of pharmaceutical preparations, and in particular to a purification method for metformin hydrochloride, a metformin hydrochloride sustained release tablet and a preparation method therefor. The purification method for metformin hydrochloride comprises the following steps: dissolving a metformin hydrochloride crude product in an aqueous ethanol solution having a volume fraction of 70-75%, adding activated carbon, adjusting the pH value to 3-5 using concentrated hydrochloric acid, then carrying out heating reflux, and then passing the filtered filtrate through cooling crystallization, separation, washing and drying, so as to obtain metformin hydrochloride. By using a specific aqueous ethanol solution having a volume fraction of 70-75% as a purification solvent and combining activated carbon for decoloration under the condition of the pH value being 3-5, the solution color of a metformin hydrochloride product obtained by purification meets required standards; in addition, a metformin hydrochloride sustained release tablet prepared from the metformin hydrochloride product has excellent stability, and after carrying out a stability acceleration test, may still maintain stable release at a certain speed within 24 hours and maintain stable blood concentration.
Inventors:
XU DANQING (CN)
YU GUOXIN (CN)
GENG LIANG (CN)
ZHU YADONG (CN)
YU GUOXIN (CN)
GENG LIANG (CN)
ZHU YADONG (CN)
Application Number:
PCT/CN2021/118204
Publication Date:
July 14, 2022
Filing Date:
September 14, 2021
Export Citation:
Assignee:
HAINAN HAILI PHARMACEUTICAL CO LTD (CN)
International Classes:
C07C277/08; A61K9/22; A61K31/155; A61K47/10; A61K47/38; A61P3/10; C07C279/26
Foreign References:
| CN112645845A | 2021-04-13 | |||
| CN103435518A | 2013-12-11 | |||
| CN104940941A | 2015-09-30 | |||
| CN101428007A | 2009-05-13 | |||
| CN102516130A | 2012-06-27 | |||
| CN106008277A | 2016-10-12 | |||
| CN102153489A | 2011-08-17 | |||
| CN108969501A | 2018-12-11 | |||
| CN104940159A | 2015-09-30 | |||
| CN101380311A | 2009-03-11 | |||
| CN101283993A | 2008-10-15 | |||
| CN111588701A | 2020-08-28 | |||
| CN1543937A | 2004-11-10 |
Attorney, Agent or Firm:
BEIJING HC-IP AGENCY CO., LTD. (GENERALPARTNERSHIP) (CN)
Download PDF:
Previous Patent: BRAZIER-TYPE GASIFICATION AND CARBONIZATION FURNACE
Next Patent: AIR INTERFACE TIME SYNCHRONIZATION METHOD AND COMMUNICATION DEVICE
Next Patent: AIR INTERFACE TIME SYNCHRONIZATION METHOD AND COMMUNICATION DEVICE