HETEROCYCLES

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.

■ DDQ Oxidation of Some Erythrinan Enones and Dienones: Syntheses of (±)-Erytharbine and (±)-Crystamidine

Yoshisuke Tsuda,* Shinzo Hosoi, Fumiyuki Kiuchi, Takehiro Sano, Jun Toda, and Ryuzo Yamamoto

*Faculty of Pharmaceutical Scicences, Kanazawa University, 13-1 Takara-machi, Kanazawa 920-0934, Japan

Abstract

DDQ oxidation of 3,8-dioxoerythrinan-1(6)-ene 1 in dioxane gave the ring C/D oxidized product, the dienone 2, while that of 3,8-dioxoerythrinan-1-ene 4 gave the ring B dehydrogenated product 5. The either product was convertible to the same trienone 3 on further oxidation in different solvents. The trienone 3a and 3b were transformed by a conventional procedure to the highly dehydrogenated oxo-erythrinan alkaloids, erytharbine 8a and crystamidine 8b, respectively.