Patent Number: 8,871,932

Title: Process for the preparation of tadalafil

Abstract: The present invention relates to a process for the preparation of tadalafil of Formula I, ##STR00001## comprising reacting a D-tryptophan compound of Formula III with piperonal in sulfolane.

Inventors: Patil; Dattatray Bapuso (Kolhapur, IN), Patel; Killol (Junagadh, IN), Prasad; Ashok (New Delhi, IN), Prasad; Mohan (Gurgaon, IN)

Assignee: Ranbaxy Laboratories Limited

International Classification: C07D 209/16 (20060101); C07D 241/36 (20060101); C07D 307/80 (20060101)

Expiration Date: 2018-10-28 0:00:00