| The genus Aphanamixis (Meliaceae), trees or shrubs, comprising about25species, are mainly distributed in Asian tropical and subtropical regions and only4species are widely distributed in China (Guangdong, Guangxi and Yunnan Provinces). Some plants in this genus are used as a folk medicine by Chinese resident to treat diseases, such as colds, rheumatoid arthritis and numbness. Previous studies revealed that the plants of this genus mainly contain triterpenes, diterpenoids, sesquiterpenoids, alkaloids, steroids, flavonoids and lignans etc.Pestalotiopsis clavispora, belonging to the genus of Pestalotiopsis, is a kind of important plant pathogen and the disease caused by them, are distributed all over the world, and most of them distributed in tropical and subtropical regions except a few distributed in south of China. Fungi of the genus Pestalotiopsis parasitize widely on the living plant leaves and twigs in about50families tropical higher plants. Pestalotiopsis species have attracted much attention of chemical researchers in recent years for their ability to produce a variety of bioactive secondary metabolites. Studies reported that crude extracts of the genus fungi had afforded structurally unique natural products, and showed inhibitory effects on replication of HIV virus.The genus Aspergillus is one of the most common categories of the Hyohomycetaceae (Moniliales). The fungi of the genus widely distributed in nature are one of the main microorganisms causing the corruption of a variety of substances. Aspergillus flavus has strong toxicity. The species are widely applied in food, medicine and commerce. For instance, Aspergillus glaucus and Aspergillus niger have strong enzyme activities, they are widely used in the sauces and wine of food fermentation. Aspergillus of diverse origins have been proven to be prolific sources of structurally interesting secondary metabolites, such as alkaloids, peptides, polyketides and terpenes, and some of them exhibited diverse biological activities, which attracted much attention of chemists and biologists. In order to investigate much more secondary metabolites of Aphanamixis grandifolia, Pestalotiopsis clavispora and Aspergullus versicolor, we studied on the chemical constiruents of the95%ethanol extracts of Aphanamixis grandifolia and the solid-state fermented culture of two species of fungi in this thesis. The chemical constituents of70compounds were isolated by means of silica gel and Sephadex LH-20gel column chromatography, MCI gel column chromatography, preparative thin layer chromatography and recrystallization etc. The structures of these compounds were elucidated on the basis of modern spectroscopic methods, including IR, EIMS, HRESIMS,1D NMR (1H NMR,13C NMR, DEPT and NOE),2D NMR (’H-’H COSY, HSQC, HMBC and NOESY) and single-crystal X-ray crystallography, and comparison with authentic samples or the data from literature,66compounds including seven new compounds and a new natural product were elucidated.23compounds were isolated and elucidated from Aphanamixis grandifolia, which were identified as sesquiterpenes, diterpenoids, triterpenoids, lignans, coumarin, flavonoids and sterols etc., one of which was new compound. And21compounds were isolated and elucidated from Pestalotiopsis clavispora. They were identified as penicillide derivatives, xanthones, dihydroisocoumarin derivatives, pyrans and sterols etc., five of which were new compounds.22compounds were isolated from Aspergullus versicolor. They were identified as bisabolane-type sesquiterpenes, diphenyl ethers, alkaloids and sterols etc., a new compound and a new natural product among of them.In the end of the thesis, one review was made on the systemic summarization for the chemical constituents and bioactivities of the genus Aphanamixis.The results of the investigation were expected to enrich the database of natural products, to afford the scientific basis of screening of new medicines, and to help the utilization of the Chinese natural resources. |
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