14-Hydroxycaryophyllene 4,5-oxide — A new sesquiterpene fromBetula pubescens
A new sesquiterpene — 14-hydroxycaryophyllene 4,5-oxide — has been isolated from the unsaponifiable part of an ethereal extract of the leaves ofBetula pubescens, and its structure has been established on the basis of chemical and spectral characteristics.
Studies of Australian soft corals. XXV. Several caryophyllene-based diterpenes from a Nephthea species
Two new caryophyllene-based diterpenes (5) and (6) are reported from the soft coral Nephthea chabrolii. The structures were deduced spectroscopically and the compounds were converted into several known diterpenes by chemical transformation. The presence of the caryophyllene ring system was based on 13C n.m.r. data and confirmed by conversion into the known clovane ring system by an acid-catalysed hydration-rearrangement of the endocyclic epoxide (12).
Systematic implications of flavonoids and sesquiterpene lactones in species of Vernonia
Abstract Systematic and evolutionary interpretations based upon the distributional data for 27 flavonoids from 39 species and 9 sesquiterpene lactones from 38 species are presented for species of Vernonia mostly from the New World.