The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 21, 2020
Filed:
May. 24, 2017
Zhejiang Huahai Pharmaceutical Co., Ltd, Taizhou, CN;
Zhejiang Huahai Zhicheng Pharmaceutical Co., Ltd., Linhai, CN;
ZHEJIANG HUAHAI PHARMACEUTICAL CO., LTD, Taizhou, CN;
ZHEJIANG HUAHAI ZHICHENG PHARMACEUTICAL CO., LTD., Linhai, CN;
Abstract
Provided is a purifying method for dabigatran etexilate free base, comprising subjecting a dabigatran etexilate free base crude product to water slurrying to obtain a crude product B; then conducting recrystallization on the crude product B with acetone and water to obtain a crude product C; and subsequently, purifying the crude product C with a mixed solvent of tetrahydrofuran and ethyl acetate, filtering and drying to obtain a dabigatran etexilate free base finished product. The purifying method of the present invention can effectively remove various impurities and is suitable for workshop production. Salts and water-soluble organic impurities are removed by purified water slurrying, impurities with a high polarity are removed by purifying with an acetone-water solution, and impurities with a low polarity are removed by purifying with a mixed solvent of tetrahydrofuran and ethyl acetate.