New Quassinoids from the Roots of Eurycoma longifolia
A new C19-skeleton quassinoid, named longilactone and three new quassinoids, 13,21-dihydroeurycomanone, 13β,21-dihydroxyeurycomanone and 14,15β-dihydroxyklaineanone were isolated from the roots of Eurycoma longifolia and their structures were established by the spectral evidences.