New resveratrol tetramers from the stem bark of Upuna borneensis.
Five new resveratrol (=5-[(E)-2-(4-hydroxyphenyl)ethenyl]benzene-1,3-diol) tetramers, upunaphenols H-J (1-3) and trans-(4) and cis-upunaphenol K (5), were isolated from the stem of Upuna borneensis (Dipterocarpaceae). Their structures were elucidated on the basis of 1D- and 2D-NMR as well as FAB-MS data. Compounds 1-3 bear a rare biphenyl bond in their frameworks. Compounds 1 and 2 have an unprecedented nonacyclic fused ring system, and compounds 2 and 3 have symmetrical structures.
Ito
Tetsuro
T
Gifu Prefectural Institute of Health and Environmental Sciences, 1-1 Naka-fudogaoka, Kakamigahara 504-0838, Japan. zvn00510@nifty.ne.jp
Ali
Zulfiqar
Z
Furusawa
Miyuki
M
Iliya
Ibrahim
I
Tanaka
Toshiyuki
T
Nakaya
Ken-ichi
K
Murata
Jin
J
Darnaedi
Dedy
D
Oyama
Masayoshi
M
Iinuma
Munekazu
M
D020448:Ericales; D015394:Molecular Structure; D024301:Plant Bark; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification; D018547:Plant Stems; D000077185:Resveratrol; D013267:Stilbenes / Q000737:chemistry* / Q000302:isolation & purification*
D010936:Plant Extracts; D013267:Stilbenes; D000077185:Resveratrol