【摘 要】
：
Two new benzopyran derivatives,1-[(rel 2S,3R)-3,5,7-trihydroxy-3,4-dihydro-2H-chromen-2-yl]ethanone(1),and 1-[(rel 25,35)-3,5,7-trihydroxy-3,4-dihydro-2H-chrome
【出 处】
：
Chinese Chemical Letters
论文部分内容阅读
Two new benzopyran derivatives,1-[(rel 2S,3R)-3,5,7-trihydroxy-3,4-dihydro-2H-chromen-2-yl]ethanone(1),and 1-[(rel 25,35)-3,5,7-trihydroxy-3,4-dihydro-2H-chromen-2-yl]ethanone(2),along with four known flavonoids,prodelphinidin C,prodelphinidin B3,(-)-epi-gallocatechin and(+)-gallocatechin,were isolated from the stems of Gouania leptostachya DC.var. tonkinensis Pitard.Their structures were determined on the basis of spectroscopic methods including HR-ESI-MS,1D and 2D NMR.Prodelphinidin C exhibited significant inhibitory activity forα-glucosidase.
Two new benzopyran derivatives, 1 - [(rel 2S, 3R) -3,5,7-trihydroxy-3,4- dihydro- 2H- chromen-2-yl] ethanone 35) -3,5,7-trihydroxy-3,4-dihydro-2H-chromen-2-yl ethanone (2) along with four known flavonoids, prodelphinidin C, prodelphinidin B3, (-) - epi-gallocatechin and (+) - gallocatechin, were isolated from the stems of Gouania leptostachya DC.var. tonkinensis Pitard. Their structures were determined on the basis of spectroscopic methods including HR-ESI-MS, 1D and 2D NMR. Prodelphinidin C demonstrate significant inhibitory activity for α -glucosidase.
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