Asai Teigo, Hara Noriyuki, Kobayashi Sawa, Kohshima Shiro, Fujimoto Yoshinori
Department of Chemistry and Materials Science, Graduate School of Science and Engineering, Tokyo Institute of Technology, Meguro, Tokyo 152-8551, Japan.
Phytochemistry. 2008 Mar;69(5):1234-41. doi: 10.1016/j.phytochem.2007.11.011.
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.
对毛泡桐未成熟果实表面粘性分泌物的甲醇提取物进行化学研究，得到了9种香叶基黄酮，6-香叶基-5,7-二羟基-3',4'-二甲氧基黄酮（1）、6-香叶基-3',5,7-三羟基-4'-甲氧基黄酮（2）、6-香叶基-4',5,7-三羟基-3',5'-二甲氧基黄酮（3）、6-香叶基-4',5,5',7-四羟基-3'-甲氧基黄酮（4）、6-香叶基-3,3',5,7-四羟基-4'-甲氧基黄酮（5）、4',5,5',7-四羟基-6-[6-羟基-3,7-二甲基-2(E),7-辛二烯基]-3'-甲氧基黄酮（6）、3,3',4',5,7-五羟基-6-[6-羟基-3,7-二甲基-2(E),7-辛二烯基]黄酮（7）、3,3',4',5,7-五羟基-6-[7-羟基-3,7-二甲基-2(E)-辛烯基]黄酮（8）以及3,4',5,5',7-五羟基-3'-甲氧基-6-(3-甲基-2-丁烯基)黄酮（9），还有6种已知的香叶基黄酮。其中，化合物4、6 - 9以及已知的6-香叶基-3',4',5,7-四羟基黄酮（双黄酮）、6-香叶基-3,3',4',5,7-五羟基黄酮（双黄醇）和3',4',5,7-五羟基-6-[7-羟基-3,7-二甲基-2(E)-辛烯基]黄酮对DPPH自由基显示出较强的清除作用。
