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:
Dec. 20, 2016
Filed:
Oct. 17, 2013
2y-chem, Ltd., Shanghai, CN;
Yanfeng Zhou, Shanghai, CN;
Yong Liu, Shanghai, CN;
Xuezhang Wang, Shanghai, CN;
Xungui He, Shanghai, CN;
Yuan Wang, Shanghai, CN;
2Y-CHEM, LTD., Shanghai, CN;
Abstract
The present invention discloses an improved process for preparing an important intermediate of linagliptin. In particular, disclosed are a process for preparing a compound V which is an important intermediate of linagliptin and has the structure V, and an industrial process of preparing linagliptin having excellent chemical and optical purities, which is an inhibitor of dipeptidyl peptidase-4 (DPP-IV), from the compound V. The process employs a phase-transfer catalyst, is high in yield, easy and simple to handle, environmentally friendly, suitable for industrial mass production, and can be implemented by a 'one-pot process'.