title: Stigmastane derivatives and isovaleryl sucrose esters from Vernonia guineensis (Asteraceae).
abstract: Vernoguinoside, 16beta,22R;21,23S-diepoxy-3beta-O-beta-D-glucopyranosyloxy-21S,24-dihydroxy-5alpha-stigmasta-8,14-dien-28-one (1), a new stigmastane derivative, 16beta,22R;21,23S-diepoxy-21S,24-dihydroxy-5alpha-stigmasta-8,14-diene-3,28-dione (2) and two new sucrose esters, 1',3,3',4',6'-pentakis-O-(3-methylbutanoyl)-beta-D-fructofuranosyl alpha-D-glucopyranoside (3) and 1',2,3',6,6'-pentakis-O-(3-methylbutanoyl)-beta-D-fructofuranosyl alpha-D-glucopyranoside (4), have been isolated from the stem bark of Vernonia guineensis. The structures of the new compounds were determined on the basis of spectroscopic evidence.
authors.affiliation: Department of Chemistry, University of Dschang, Box 67, Dschang, Cameroon.
authors.forename: Alembert T
authors.initials: AT
authors.lastname: Tchinda
authors.forename: Pierre
authors.initials: P
authors.lastname: Tane
authors.forename: Johnson F
authors.initials: JF
authors.lastname: Ayafor
authors.forename: Joseph D
authors.initials: JD
authors.lastname: Connolly
mesh_terms: D015394:Molecular Structure; D024301:Plant Bark / Q000737:chemistry; D012855:Sitosterols / Q000302:isolation & purification*; D035741:Vernonia / Q000737:chemistry*
chemical_list: D012855:Sitosterols