Prenylated Indole Alkaloids from Flustra foliacea with Subtype Specific Binding on NAChRs

Abstract

Several brominated indole alkaloids and a diterpene (1 - 7) were isolated from the dichloromethane extract of the North Sea Bryozoan Flustra foliacea. Alkaloid 4 is a new natural product, whose structure was elucidated by interpretation of spectroscopic data (NMR, mass, UV, and IR). All compounds were tested for their in vitro affinity towards the α4ß2* and α7* subtype of the neuronal nicotinic acetylcholine receptor (nAChR) using radioligand binding assays. Deformylflustrabromine (3) and deformylflustrabromine B (4) were shown to have affinities in the lower micromolar range for nAChRs, differing in their subtype preference.

Key words

Flustra foliacea - alkaloids - nicotinic acetylcholine receptors

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