| Naturally occurring oligostilbenes constitute a type of rapidly growing compounds with complex structures and multi-faceted activities. The chemical studies on naturally occurring oligostilbenes have been reviewed in the thesis, a new classification method was put forth for the first time. As part of our researching new active oligostilbenes from plants, the roots of Vitis amurensis and the lianas of Gnetum hainanense have been investigated. Fifty-five stilbenoids, including thirty-three new oligostilbenes, were isolated from these two plants.Fifteen new oligostilbenes, named amurensins A-0 (1-15), including two pentamers, five tetramers, five trimers, three dimers, have been isolated from the roots of Vitis amurensis along with twelve known oligostilbenes: resveratrol (16), (+)-ε-viniferin (17), e-viniferin diol (18), ampelopsin A (19), ampelopsin F (20), ampelopsin D (21), ampelopsin E (22), (+)-hopeaphenol (23), isohopeaphenol (24), vitisin A (25), (+)-vitisifuran A (26), and heyneanol A (27). Their structures were characterized unambiguously on the basis of chemical and spectroscopic evidence, especially on 2D NMR techniques. Amurensins B (2), C (3) and J (10) were the first naturally occurring resveratrol trimers and tetramer with a cis dihydrobenzofuran moiety. Amurensins D-F (4-6) were the first oligostilbenes containing an unsaturated benzofuran ring on which the positions of the 4-hydroxybenzene group and the 3,5-dihydroxybenzene group were interchanged comparing with other oligostilbenes having a benzofuran ring.Conformations of the seven-membered ring in some oligostilbenes were discussed for the first time. A special phenomenon of some compounds caused by spatial congestion was studied on the basis of their ~1H NMR spectra at various temperatures, which further confirmed the accuracy of their structures. The biosynthesis of oligostilbenes in Vitis amurensis has been proposed.
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