IP Library Granted Patent US 8,445,698
Granted Patent B2
US 8,445,698 · App. 12/666,606 · Granted May 21, 2013

Process for the preparation of an intermediate of tadalafil

Inventors: Dattatray B. Patil (Kolhapur, IN); Killol Patel (Janagadh, IN); Ashok Prasad (New Delhi, IN); Mohan Prasad (Gurgaon, IN)
Assignee: Ranbaxy Laboratories Limited
View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 8,445,698
App. No.
12/666,606
Granted
May 21, 2013
Kind
B2
Abstract

The present invention relates to a process for the preparation of cis-intermediate of Formula II, which is useful synthetic intermediates in the preparation of tadalafil.

Claims (6)

1. A process for the preparation of the cis-intermediate of Formula II,

wherein the process comprises,

reacting a D-tryptophan compound of the Formula III or a pharmaceutically acceptable salt thereof,

with a compound of Formula IV,

in the presence of sulfolane.

2. The process according to claim 1 wherein the process is carried out at a temperature of 50-100° C.

Assignments (2)
MERGER Recorded Jan 13, 2016
From: RANBAXY LABORATORIES LIMTED
To: SUN PHARMACEUTICAL INDUSTRIES LIMITED
Reel/Frame 037513/0475 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Feb 22, 2010
From: PATIL, DATTATRAY B.; PATEL, KILLOL; PRASAD, ASHOK; PRASAD, MOHAN
To: RANBAXY LABORATORIES LIMITED
Reel/Frame 023971/0203 →
Priority Claims (1)
IN 1402/DEL/2007 · Jun 29, 2007 · national
Continuity (1)
Related Publication 20100228030A1 · Sep 9, 2010