Studies On The Chemical Constituents Of Gynura Nepalensis And The Flower Of Juglans Regia

Gynura nepalensis DC. belonging to the family of Compositae, mainly distributed in Guizhou, Yunnan and other places of China. Gynura nepalensis bears analgesic, hemostatic, cooling-blood, stasis-swelling and other pharmacological properties. Chemical constituents of other Gynura species have been reported in literatures, including alkaloids, volatile oils, terpenes, amino acids, flavonoids, and other types of compound. However, there is still no report about the chemical composition of Gynura nepalensis. This thesis took advantage of some isolation and purification technologies, such as solvent extraction, preliminary solvent isolation, column chromatographies over silica gel and Sephadex LH-20 gel, and preparative HPLC procedure, to investigate the chemical constituents of the stems of Gynura nepalensis, with 26 compounds (1*-26*) being isolated and structurally determined from the 95% EtOH extract. Names and structures of the purified compounds are listed in Table 1 and Figure 1, respectively. Among them, compound 1* is a new neolignan, compound 25* is a new monoterpene, compound 26* is a new alkaloid. Known compounds are classified as follows:lignans (2-4), diterpenes (5-10,19,24), alkaloids (13-15,17,20), steroids (21,22), and others (11,12,16,18,23). All of the above compounds were isolated from the title plant for the first time. Some compounds were evaluated for pharmacological activities, such as cytotoxicity against several cancer cell lines, anti-osteoporosis, and protection of H2O2 injuried HUVEC cell properties, with no activity being found.Juglans regia Linn, belonging to the plant family of Juglandaceae, (in this thesis we studied the flower of Juglans regia), mainly distributed in northern, northwestern, southwestern, southern, and eastern part of China. Shizhen Li, a great medical scientist in Ming dynasty, summarized the medical value of walnut as "enriching the blood, moistening phlegm, benefiting vital, benefiting viscera, nourishing lung, and clearing intestine, etc." Some chemical constituents of Juglans have been reported in literatures, including quinone, flavonoids, diarylheptanoids, terpenes, volatile oils, and others. This thesis took advantage of some isolation and purification technologies, such as solvent extraction, preliminary solvent isolation, column chromatographies over silica gel and Sephadex LH-20 gel, and preparative HPLC procedure, to investigate the chemical constituents of the flower of Juglans regia, with 8 compounds (1-8) being isolated and structurally determined from the 80% EtOH extract. Names and structures of the purified compounds are listed in Table 2 and Figure 2, respectively.