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:
Mar. 26, 2013
Filed:
Nov. 04, 2009
Manne Satyanarayana Reddy, Hyderabad, IN;
Chakilam Nagaraju, Hyderabad, IN;
Achampeta Kodanda Ramprasad, Hyderabad, IN;
Manne Satyanarayana Reddy, Hyderabad, IN;
Chakilam Nagaraju, Hyderabad, IN;
Achampeta Kodanda Ramprasad, Hyderabad, IN;
MSN Laboratories Limited, Hyderabad, Andhra Pradesh, IL;
Abstract
The present invention relates to improved processes for the preparation of endolthelin receptor antagonists darusentan and ambrisentan, their salts and intermediates. Processes for the preparation of darusentan and ambrisentan comprise reacting benzophenone with a compound of Formula-3 to provide a compound of Formula-4, which on in-situ treatment with methanol and a suitable acid provides a compound of Formula-5; hydrolyzing the compound of Formula-5 to provide a compound of Formula-6; resolving the compound of Formula-6 to provide a compound of Formula-7; esterifying the compound of Formula-7 to provide a compound of Formula-8; reacting the compound of Formula-8 with a compound of Formula-9 to provide a compound of Formula-10; hydrolyzing the compound of Formula-10 to provide darusentan or ambrisentan; and purifiying darusentan or ambrisentan to provide darusentan or ambrisentan having purity greater than 99.00% by HPLC.