| The discovery of paclitaxel with its remarkable anti-cancer activity has been a distinguished progress in natural product chemistry during the past 20 years. Paclitaxel is a widely used medicine due to its excellent effects; however, it couldn't supply clinical application as a result of its low yield in Taxus plants. Twigs and leaves are considered to be the promising sources of taxane-type diterpenoids because they can be collected without the destruction of the trees. We have further investigated the chemical constituents of the twigs and leaves from Taxus cuspidata which grows in Liaoning province.This paper described the isolation and structure elucidation of the constituents from the twigs and leaves of Taxus cuspidata Sieb.et Zucc. The compounds were isolated by chromatography on silica gel and Sephadex LH-20 columns and NMR spectral analysis were employed for their structure identification. 17 compounds were obtained and 15 of them were elucidated as: taxusfl-avone A (1), amentoflavone (2), quercetin (3), kaempferol (4), taxifolin (5), dihydrokaempferol (6), taxinine (7), taxinine A (8), taxinine B (9), taxacin (10), ponasterone A (11), daucosterol (12), taxicatin (13), p-hydroxy benzaldehyde (14), p-hydroxybenzcic acid (15), respectively. Among them, compound 1 was a novel compound, and compound 5, 6, 14, 15 were isolated from this plant for the first time, furthermore, the proton and carbon signals of taxacin were assigned by means of 2D NMR techniques including HMBC and HMQC for the first time, too. |
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