Three Structural Transformation Of The Natural Compounds

This dissertation is composed of three parts. Part A described the structure modification and activity screening of bergenin. Part B elaborated the studies on the preparation of norcantharidin-like compounds obtained from the reactions of hedychenone and maleic acid anhydride. Part C reported the synthesis of mototerpene alkaloid-like compounds. The structure modification and biological activity research of geniposide and genipin were summarized.Part A The structure modification and activity screening of bergeninThis part reported the reactions of bergenin and some different secondary amines and biological activity screening. Bergenin is an important natural product. Given the in some cases well-investigated incorporation of nitrogen atoms into baicalein, the presumably biomimetic synthesis of nitrogen-containing derivatives from the secondary amines starting materials, bergenin, may be rewarding. As a result, 18 derivatives were prepared. Preliminary bioactivity tests of some products were performed. These products did not show inhibition effect against diabetes PTP1B target enzyme, and they did not depress HIV-1 RT. Part B The preparation of norcantharidin analogueThis part showed the preparation of norcantharidin analogue. In order to synthesize norcantharidin analogues, we underwent Diels-Alder reaction of furanoditerpene with maleic acid anhydride and obtained mainly thermodynamic product. Hedychenone is kind of furanoditerpenes. The norcantharidin analogue obtained from hedychenone was instable, so it was catalytically hydrogenized, and a stable compound was afforded.Part C Studies on the synthesis of genipin derivatives and their activity screeningThis part reported the synthesis of genipin derivatives and their biological activity screening. The methods were listed below: (1) Reaction of genipin and ethylenediamine; (2) Reaction of the product of (1) and formaldehyde. Preliminary bioactivity tests of these products were performed. These products did not show inhibition effect against diabetes PTP1B target enzyme, and and they did not depress HIV-1 RT.