Phytochemical Studies On Terpenoids From Four Traditional Chinese Medicines

This doctoral dissertation covers the phytochemical studies on terpenoids from four different traditional Chinese medicines and one alga, including the flowers of Inula britannica (Xuan-Fu-Hua in Chinese Pharmacopoeia), the resinous exudates of Commiphora opobalsamum (Mo-Yao in Chinese Pharmacopoeia), the root barks of Dictamnus dasycarpus (Bai-Xian-Pi in Chinese Pharmacopoeia), the rhizomes of Cyperus rotundus (Xiang-Fu in Chinese Pharmacopoeia), and a marine red alga Grateloupia turuturu.Based on the NMR-guided fractionation, including extraction, silica gel CC (column chromatography), ODS CC, Sephadex LH-20CC, PTLC (preparative thin layer chromatography) and crystallization, there have been72compounds obtained, including20new sesquiterpenoids,6new triterpenoids (including2new limonoids), and2new alkaloids (Table for the Information of New Compounds). All of the structures were elucidated by extensive spectrascopic methods, including IR,UV,CD,EIMS,ESIMS,HRESIMS,1HNMR,13CNMR,DEPT-135,1DNOE difference spectra,NOESY,1H-1H COSY,HSQC,HMBC. Among these, the structures of11compounds have been confirmed by single-crystal X-ray diffraction method, and the absolute configurations of11compounds have been determined by single-crystal X-ray diffraction method, CD exciton chirality methods, or chemical transformations.In addition, we gave a review which summarized the secondary metabolites reported from Ligularia species as well as their biological activities in recent decades (1990.1-2011.6). The conclusions indicate that Ligularia genus may be a rich source of natural products with chemical and biological diversity.