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. 07, 2021
Filed:
Jan. 03, 2019
Piramal Pharma Limited, Mumbai, IN;
Milind Gharpure, Maharashtra, IN;
Ashutosh Jagtap, Maharashtra, IN;
Changdev Raut, Maharashtra, IN;
Navnath Patil, Maharashtra, IN;
Prashant Ladkat, Maharashtra, IN;
Jaisankar Krishnapillai, Maharashtra, IN;
Nirmal Kumar Manoharan, Maharashtra, IN;
Kumaravel Kandasamy, Maharashtra, IN;
PIRAMAL PHARMA LIMITED, Mumbai, IN;
Abstract
The present invention provides an improved process for preparation of the L-threo-(2S,3R)-3-(3 4-dihydroxyphenyl)serine (I) or a salt thereof, which is known as Droxidopa; comprising (a) recovery of the by-product compound (V) (as described herein) from the crude compound (I), and (b) recycling and re-use it for the preparation of droxidopa. Accordingly, the present invention relates to an improved economical process for the preparation of L-threo-(2S,3R)-3-(3.4-dihydroxyphenyl)serine (I) or its pharmaceutically acceptable salts; wherein the process relates to recovery and recycling of the by-product compound (V) and also to re-use it for the preparation of droxidopa.