Estudo Químico de Vernonia diffusa

Abstract

In this work we reviel the phytochemical study of the wood's extract of Vernonia diffusa Less., which was collected in the Atlantic forest in Barra do Piraí - R.J.- Brasil and identified by Dr. Heber dos Santos Abreu (I.F.-UFRRJ). The fractionation by solvent partition, crystallization and chromatographic tecniques of the organic extract yielded flavonoid derivatives which have not been found previously in Vernonia genus. The analysis of IR and 13C NMR spectra data of the natural constituents, of the acetyl derivatives and of the hidrolysis products let us to identify 5,3'-dihydroxy-4'-methoxy flavanone-7-O-b-D-glucopyranosyl (6"-1"')-b-Drhamnopyranoside (hesperidin), 5-hydroxy-3'-4'-dimethoxy-flavanone-7-O-b-Dglucopyranosyl (6"-1"') b-D-rhamnopyranoside (3-methoxyHesperidin) and a-Dglucopyranosyl (1-2')-b-D-fructopyranoside (sucrose). A review of the chemical constituents of Vernonia genus with special attention to the flavonoids and also occurrence beside pharmacological study of hesperidin, an abundant constituent in this specie was includie