Online article for Non-subscribers

Pay per view

Heterocycles has a pay-per-view service for Non-subscribers.
You will be able to directly purchase the full text article through PayPal.
Your purchased Paper can be downloaded after the payment is completed.
An e-mail will be sent the URL to download the paper.
If you have any questions, please contact: purchase@heterocycles.com

Price: ¥ 4,400 (Yen only)
Period: This Article can be accessed for 7 days.

Communication | Special issue | Vol 37, No. 1, 1994, pp.239-243
Published online, 1st January, 1970
DOI: 10.3987/COM-93-S41
Synthesis of 4,6-Dihydro-4-oxopyrido[2,1-a]isoindoles and 4,6-Dihydro-6-oxothieno[2',3',:3,4]pyrrolo[1,2-a]pyridines

Serge Burner, Rolf Canesso, and Ulrich Widmer*

*Pharma Division, Preclinical Research, F.Hoffmann-La Roche Ltd., CH-4002 Basel, Switzerland

Abstract

Tricyclic pyridones (3) which are important intermediates for the preparation of potent benzodiazepine receptor ligands were obtained by different chemical routes. Key reaction in the so far optimal synthesis of 3a is the base catalyzed ring contraction reaction of 2 to intermediate (13). Under similar reaction conditions, however, thiophene derivative (14) yielded instead of the analogous acid (16), the nitrile (15). In two additional steps the final product (3b) was obtained in good yield.