Article

Alkaloids from Hippeastrum papilio.

Departament de Products Naturals, Biologia Vegetal i Edafologia, Facultat de Farmàcia, Universitat de Barcelona, Av. Joan XXIII s/n, E-08028 Barcelona, Spain.
Molecules (Impact Factor: 2.43). 01/2011; 16(8):7097-104. DOI: 10.3390/molecules16087097
Source: PubMed

ABSTRACT Galanthamine, an acetylcholinesterase inhibitor marketed as a hydrobromide salt (Razadyne®, Reminyl®) for the treatment of Alzheimer's disease (AD), is obtained from Amaryllidaceae plants, especially those belonging to the genera Leucojum, Narcissus, Lycoris and Ungernia. The growing demand for galanthamine has prompted searches for new sources of this compound, as well as other bioactive alkaloids for the treatment of AD. In this paper we report the isolation of the new alkaloid 11β-hydroxygalanthamine, an epimer of the previously isolated alkaloid habranthine, which was identified using NMR techniques. It has been shown that 11β-hydroxygalanthamine has an important in vitro acetylcholinesterase inhibitory activity. Additionally, Hippeastrum papilio yielded substantial quantities of galanthamine.

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