Geranylated flavanones from the secretion on the surface of the immature fruits of Paulownia tomentosa.
Chemical investigation of the methanol extract of the viscous secretion on the surface of immature fruits of Paulownia tomentosa furnished nine geranylated flavanones, 6-geranyl-5,7-dihydroxy-3',4'-dimethoxyflavanone (1), 6-geranyl-3',5,7-trihydroxy-4'-methoxyflavanone (2), 6-geranyl-4',5,7-trihydroxy-3',5'-dimethoxyflavanone (3), 6-geranyl-4',5,5',7-tetrahydroxy-3'-methoxyflavanone (4), 6-geranyl-3,3',5,7-tetrahydroxy-4'-methoxyflavanone (5), 4',5,5',7-tetrahydroxy-6-[6-hydroxy-3,7-dimethyl-2(E),7-octadienyl]-3'-methoxyflavanone (6), 3,3',4',5,7-pentahydroxy-6-[6-hydroxy-3,7-dimethyl-2(E),7-octadienyl]flavanone (7), 3,3',4',5,7-pentahydroxy-6-[7-hydroxy-3,7-dimethyl-2(E)-octenyl]flavanone (8), and 3,4',5,5',7-pentahydroxy-3'-methoxy-6-(3-methyl-2-butenyl)flavanone (9), along with six known geranylated flavanones. Among these, compounds 4, 6-9 and the known 6-geranyl-3',4',5,7-tetraahydroxyflavanone (diplacone), 6-geranyl-3,3',4',5,7-pentahydroxyflavanone (diplacol) and 3',4',5,7-pentahydroxy-6-[7-hydroxy-3,7-dimethyl-2(E)-octenyl]flavanone showed potent radical scavenging effects towards DPPH radicals.
Asai
Teigo
T
Department of Chemistry and Materials Science, Graduate School of Science and Engineering, Tokyo Institute of Technology, Meguro, Tokyo 152-8551, Japan.
Hara
Noriyuki
N
Kobayashi
Sawa
S
Kohshima
Shiro
S
Fujimoto
Yoshinori
Y
D044950:Flavanones / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism*; D005638:Fruit / Q000737:chemistry* / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy / Q000379:methods / Q000592:standards; D015394:Molecular Structure; D012015:Reference Standards; D028083:Scrophulariaceae / Q000737:chemistry*; D013237:Stereoisomerism; D013499:Surface Properties
D044950:Flavanones