| Medicinal animals and plants are the major sources of lead compounds. However, some of them are on the edge of extinction owing to over-exploitments and environment deterioration. The medicinal resource conservation and the drug supply became the key of the drug R & D. Secondary metabolite of micro-organisms and the chemical modification and synthesis of chemical ingredients were considered as two feasible ways to discover the new drug sources because of their sampling in small quantity, reproduction speed, little ecological damage, and easy achievement of large-scale production.Our study focused on the effective chemical ingredients of medicinal plants and the bioactive compounds of endophytic fungi to obtain the structurally novel and bioactive compounds. Furthermor, we attempted to modify the strutures of the components from medicinal plants to get the bioactive derivatives. This dissertation contents of three sections: i. Investigations of effective components from Ipomoea pes-caprae, Euphorbia helioscopia and Myristica fragrans; ii. Screening of talented strains and study on bioactive compounds of endophytic fungi from Ipomoea pes-caprae by integrated TLC and HPLC-UV methods. iii. Chemical modifications of euphorin from Euphorbia helioscopia by introducing a bioactive moiety——N- benzoyl-(2R,3S)-3-phenylisoserine or N-tertiary butyloxycarbonyl-(2R, 3S)-3-phenyl- isoserine, and biological evaluation and SAQR analysis of the derivatives.As the results, compounds 1–13 from Ipomoea pes-caprae, compounds 16–28 from Euphorbia helioscopia, and compounds 29–45 from Myristica fragrans were isolated and identified by spectroscopic and the chemical methods, among which 14 compounds (1–8, 16, 30–34) were the new structures and 5 compounds (30–34) were novel structures with a diarylnononoid and a neoligan moieties. Six of them exhibited cytotoxic activities on a panel of cancer cells, and thirteen compounds owned anti-oxidative effect against DPPH. 18 Strains of endophytic fungi were isolated from Ipomoea pes-caprae, and one of them that was indentified as Fusarium oxysporum J8-1-2 is an engineering strain producing a cytotoxic alkaloid (compound 55, 27.3% yield) against HL-60 and A-549 cells with IC50 values of 1.2 and 2.3μg/mL, respectively. The metabolites of another two endophytic fungi, Y16 and Fusarium oxysporum Y24-2, were studied. Six new compounds (47, 49, 50, 52, 53) together with 4 known ones (46, 48, 51, 54) from Y16, and a new compound (56) together with 2 known ones (28 and 57) from Fusarium oxysporum Y24-2 were isolated and identified. The new compounds included three butyrolactone derivatives (47, 49, 50) and three ergosterones (52, 53, 56). Eleven new jatrophane diterpence derivatives (R1–R3, M1-1, M2B-1, T1-1, T1-2, T2B-1, T2C-1, T2A-2, T2B-2) with taxol and docetaxel side groups were obtained by chemical modification on euphorin, and three derivatives (R2, T2B-1 and T2A-2) of them exhibited ctotoxicity against HL-60 and A-549 cell lines.In summary, 31 new compounds and 35 known ones were obtained in this dissertation, and 23 of these compounds showed cytotoxic and antioxidative activities.
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