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Covalent bonding of azoles to quaternary protoberberine alkaloids

✍ Scribed by Lenka Grycová; Dagmar Hulová; Lukáš Maier; Stanislav Standara; Marek Nečas; Filip Lemière; Radovan Kareš; Jiří Dostál; Radek Marek

Publisher
John Wiley and Sons
Year
2008
Tongue
English
Weight
168 KB
Volume
46
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

Adducts of the quaternary protoberberine alkaloids (QPA) berberine, palmatine, and coptisine were prepared with nucleophiles derived from pyrrole, pyrazole, imidazole, and 1,2,4‐triazole. The products, 8‐substituted 7,8‐dihydroprotoberberines, were identified by mass spectrometry and 1D and 2D NMR spectroscopy, including ^1^H^15^N shift correlations at natural abundance. In addition, two adducts of QPA with chloroform and methanethiolate were characterized by using NMR data. Single‐crystal X‐ray structures of 8‐pyrrolyl‐7,8‐dihydroberberine, 8‐pyrazolyl‐7,8‐dihydroberberine, and 8‐imidazolyl‐7,8‐dihydroberberine are also presented. Copyright © 2008 John Wiley & Sons, Ltd.

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