| Our research group reported a new polyoxygenated cyclohexene-zeylenone and its antitumour activities for the first time in 1998, since then, we persisted in study on polyoxygenated cyclohexenes for several years. In order to research the resourse of Uvaria species and to discover more antitumor agents from nature, Uvaria kweichowensis growing in Guizhou province was subjected to phytochemical studies. Thirteen compounds from the 95% ethanols extract of stems and seventeen compounds from the 95% ethanols extract of leaves were isolated using silical gel and Sephedax LH-20 colomn chromatography and structurally identified by means of various modern spectroscopic techniques (NMR, MS, IR,UV and so on ) and based upon their physical properties. Among them, five were new compounds, including four polyoxygenated cyclohexenes and one diamide, which were named as kweichowenol A, kweichowenol B, kweichowenol C, kweichowenol D and uvaridiamide, and eleven were isolated in Uvaria genus for the first time. The antitumor activity of polyoxygenated cyclohexenes from Uvaria kweichowensis were tested using MTT method. From the pharmacological results, compound kweichowenol B was found to show more potent activity than others. The amount and types of polyoxygenated cyclohexenes were added through the systemic studies of phytochemistry of Uvaria kweichowensis, which will provide some referrences to the chemical taxology of Uvaria genus; the assessment of their antitumor activities of polyoxygenated cyclohexenes from Uvaria kweichowensis will provide some references... |
