Stigmastane derivatives and isovaleryl sucrose esters from Vernonia guineensis (Asteraceae).
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.
Tchinda
Alembert T
AT
Department of Chemistry, University of Dschang, Box 67, Dschang, Cameroon.
Tane
Pierre
P
Ayafor
Johnson F
JF
Connolly
Joseph D
JD
D015394:Molecular Structure; D024301:Plant Bark / Q000737:chemistry; D012855:Sitosterols / Q000302:isolation & purification*; D035741:Vernonia / Q000737:chemistry*
D012855:Sitosterols