title: Structure of a novel phytoecdysteroid, vitexirone, and efficient isolation of phytoecdysteroids fromVitex fisherii.
abstract: A novel phytoecdysteroid, vitexirone, has been isolated from a MeOH extract of the root bark of the East African medicinal plantVitex fisherii by recycling high-performance liquid chromatography on a semipreparative scale. In addition, three known phytoecdysteroids, 20-hydroxyecdysone, ajugasterone C, and turkesterone, also were isolated. The structure of vitexirone has been established spectroscopically. The position and stereochemistry of the 11-α-hydroxy group of ajugasterone C and vitexirone were confirmed by the(1)H-(1)H homonuclear COSY NMR data. These phytoecdysteroids disrupt the molting process of the pink bollwormPectinophora gossypiella.
authors.affiliation: Division of Entomology and Parasitology College of Natural Resources, University of California, 94720, Berkeley, California.
authors.forename: I
authors.initials: I
authors.lastname: Kubo
authors.forename: Y
authors.initials: Y
authors.lastname: Asaka
authors.forename: M J
authors.initials: MJ
authors.lastname: Stout
authors.forename: T
authors.initials: T
authors.lastname: Nakatsu