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:
Oct. 06, 2015
Filed:
Aug. 26, 2011
Vinayak Govind Gore, Maharashtra, IN;
Vinay Kumar Shukla, Maharashtra, IN;
Sandeep Mekde, Maharashtra, IN;
Suresh Hasbe, Maharashtra, IN;
Shreyas Bhandari, Maharashtra, IN;
Dhananjay Shinde, Maharashtra, IN;
Madhukar Shaligram Patil, Maharashtra, IN;
Vinayak Govind Gore, Maharashtra, IN;
Vinay Kumar Shukla, Maharashtra, IN;
Sandeep Mekde, Maharashtra, IN;
Suresh Hasbe, Maharashtra, IN;
Shreyas Bhandari, Maharashtra, IN;
Dhananjay Shinde, Maharashtra, IN;
Madhukar Shaligram Patil, Maharashtra, IN;
Generics [UK] Limited, Albany Gate, Darkes Lane, Potters Bar, Hertfordshire, GB;
Abstract
The present invention relates to an improved process for the preparation of Letrozole (I) and its synthetic intermediate 4-[(1-(1,2,4-triazoly)methyl]benzonitrile (III). In particular, it relates to a process to prepare Letrozole and its intermediate (III) substantially free from regioisomeric impurities. The present invention further relates to acid addition salts of 4-[(1-(1,2,4-triazoly)methyl]benzonitrile (III) such as the oxalate salt, and also to Letrozole (I), the intermediate (III) and salts thereof preparable by the processes of the present invention.