Casticin, chrysoplenol D, luteolin, p-hydroxybenzoic acid, D-fructose and isoorientin were isolated and identified from two of the pharmacologically active fractions from the leaves of Vitex negundo, L. ("lagundi"). These compounds were obtained from two fractions that exhibit relaxation of cat's trachea. This is the first report of the occurrence of casticin, chrysoplenol D and isoorientin in the leaves of V. negundo. The pharmacologic significance of the presence of flavonoids in the active fraction is briefly discussed.