Estudo químico de Lafoensia glyptocarpa Koehne (Lytraceae) e Wedelia paludosa D. C. (Asteraceae)

Abstract

This work describes part of the phytochemical study of two brazilian plants: Lafoensia glyptocarpa Koehne and Wedelia paludosa D.C.. The allelopathic effect responsible for the inhibition of germination of seeds of Lafoensia glyptocarpa Koehne (Lythraceae) has motivated the chemical investigation of the plant's aerial parts. The specimen of Lafoensia glyptocarpa Koehne was collected in the Horto Florestal- Seropedica, Itaguaí - RJ. The hexanin and ethyl acetate extracts from branches and fruits were fractionated by column chromatography and crystallization of the different fractions afforded sitosteryl acetate, butirospermyl acetate, sitosteryl cynnamate, an alkyl-ferrulate, an alkylcummarate, triglycerides, ketones and aliphatic esters. The pharmacological activity of similar substances isolated from other Wedelia species, served as a stimulus to the phytochemical investigation of this plant. The specimen of Wedelia paludosa D.C.(Asteraceae) was collected near the Londrina state University. Column chromatography of the ethereal extract of Wedelia paludosa D.C.flowers afforded stigmasterol, kaur-16-en-19-oic-acid, kaur-9,16-dien-19-oic-acid, a mixture of aliphatic esters and olefins, 3-b-O-acyl-olean-12-en-28-ol and a mixture of 3.b-D-glycopiranosyl-sitosterol and 3-b-D-glycopiranosyl-stigmasterol