The patent number 9810658.8 is incorrect. It should be 8 digits plus a check code and 9 digits.
The second patent can be found, but it was terminated in 2003 due to non-payment of fees. And this patent seems to have nothing to do with the two drugs you mentioned. There are many counterfeit patented medicines now, so be careful not to be fooled.
Application number: 98110601 Application date: 1998/01/05
Publication date: 1998/08/19 Announcement date: 2000/07/05
Public No.: 1190656 Announcement No.: 1054132
Authorization Date: Authorization Announcement Date: 2000-7-5
Patent Category: Invention Country Province and City Code: 31[China|Shanghai] < /p>
Agency code: 31203[Comparison table] Agent: Luo Dachen
Name of invention: A method for separating thymidine from a mixture
International classification number: C07H 1/06;C07H 19/06
Category classification number: 18G
Inventor: Qiu Weiran; Shao Rensen; Shao Xuefeng
Applicant: East China University of Science and Technology ;Shanghai Libo Biochemical Factory
Applicant address: No. 130, Meilong Road, Shanghai
Postcode: 200237
Abstract:
The present invention belongs to the technical field of biochemical engineering and relates to a method for separating thymidine from a mixture. Said method flows the thymidine solution containing impurities obtained by chemical synthesis through the macroporous phenolic weak acid cation exchange resin and the macroporous weak base acrylic anion exchange resin in sequence, and adds an appropriate amount of borate to the solution. , to improve the purity of thymidine products; for the thymidine solution obtained by enzymatic hydrolysis, a strong acidic cation exchange resin can be added to better remove impurities in the solution. The method of the invention has simple process, high product yield, and a purity of more than 99%, and can meet the needs of industrial production.
Main claim:
A method for separating thymidine from a mixture, mainly including the processes of impurity removal, concentration (2), crystallization (3), and filtration (4) , which is characterized in that the removal of impurities is carried out as follows: the thymidine aqueous solution containing impurities flows through two series-connected ion exchange resin columns in sequence. The ion exchange resin columns are macroporous phenolic weak acid cation exchange resin columns ( 1) and macroporous weak base acrylic anion exchange resin column (2).
Priority Item:
PCT Item
Legal Status: [Disclaimer] 2003-2-26; Termination due to expenses