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.

■ Development of a New Synthetic Strategy for Procyanidin Dimer Condensation Using Peracetylated Electrophiles

Sayaka Ishihara, Syoma Doi, Kota Harui, Taisuke Okamoto, Shuhei Okamoto, Joji Uenishi, Takashi Kawasaki, Noriyuki Nakajima,* and Akiko Saito*

*Department of Biotechnology, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Kosugi, Toyama 939-0398, Japan

Abstract

Proanthocyanidins, also known as condensed tannins and/or oligomeric flavonoids, are found in many edible plants and show interesting various biological activities. We report a simple new proanthocyanidin synthesis strategy in which an electrophile derived from a flavan-3-ol peracetate is condensed with 1.5 eq. of a benzylated nucleophile. We demonstrate here the synthesis of procyanidin B1, a (−)-epicatechin-(4β-8)-(+)-catechin dimer, to demonstrate the utility of this method. This strategy is applicable for the synthesis of various commercially available flavan-3-ol and various oligomeric flavonoids.