Bioactive polychlorinated bibenzyls from the liverwort Riccardia polyclada

3 pages, 2 tables.-- PMID: 18020419 [PubMed].-- Printed version published on Dec 28, 2007.GC-MS and 1H NMR spectroscopic profiling of a CDCl3 extract of the liverwort Riccardia polyclada (syn. R. umbrosa) revealed the presence of four main compounds bearing several chlorine atoms on a bibenzyl skeleton. Separation of a CH2Cl2 extract was achieved using preparative TLC, and structures 1–4 were proposed on the basis of spectroscopic evidence. Compounds 1–4 were active in a brine shrimp lethality bioassay (Artemia salina). In addition, 2 and 4 displayed moderate antifeedant activity in disk-choice bioassays with Spodoptera littoralis larvae and inhibited the growth of Cladosporium herbarum cultures on TLC plates.This research was supported by a grant from the Chemistry Department of the Facultad de Ciencias, Universidad de Chile, and by a Higher Education Link (SAN/984/117) from the British Council in Santiago. Financial support of CYTED (Spain) and Xarxa de Productes Naturals (Barcelona, Spain) is also acknowledged.Peer reviewe