Studies On The Chemical Constituents And Bioactivities Of Hypericum Attenuatum Choisy

Two chapters were included in the dissertation. In the first chapter, the chemical constituents of H. attenuatum were systematic studied. Moreover, the cytotoxic and anti-HIV-1activities of the new compounds were also screened. In the second chapter, studies on the chemical constituents of the genus Hypericum in the last five years were summarized.Hypericum attenuatum is a common chinese herbal medicine, which belongs to the family Guttiferae and the genus Hypericum. It is widely distributed in Heilongjiang, Jilin, Liaoning, Inner Mongolia, Shaanxi, Gansu, Shandong, Jiangsu, Anhui, Zhejiang, Jiangxi, Henan, Guangdong, and Guangxi (north) provinces. It usually grows in fields, semi-wet meadows, grasslands, hillside grass, gravel, the grass, and forest at an elevation of below1100meters. Its whole plant is mainly used for haemostasia, analgesia and stimulation of lactation in the folk. The aerial parts of H. attenuatum are used for centries in treatment of hemoptysis, hematemesis, bleeding, rheumatism, neuralgia, bruises, lack of lactation, and mastitis. They are applied to topical treatment of traumatic bleeding, swollen carbuncle and poison boils.By means of chromatography, X-ray, ECD calculation, and spectroscopic evidences,82compounds were isolated and identified from H. attenuatum, including27new compounds. Several types of PPAPs, simple phloroglucinols, xanthones, flavones, steroids, and some other compounds were contained. Hyperattenin J (20) features a unique furan-fused adamantyl core structure with an unusual hemiacetal group. Hyperattenin A (41) was characterised as a bicyclo[3.3.1]nonane derivative containing an unusual hemiacetal functionality formed by a series of redox reactions on its side chains, which occurs rarely in nature. Known compounds8-14,16,19,21-28,30,34-40,49,51,61-76, and78were isolated from Hypericum attenuatum for the first time. The absolute configurations of most of the new compounds were determined by ECD and X-ray diffraction, which is very helpful for the further research on PPAPs with small polar and great difficulty to determine their absolute configurations.In addition, some of new compounds were tested for cytotoxic activity and anti-HIV-1activity in vitro. Most of tested compounds showed moderate cytotoxic activity, and hyperattenin Ⅰ (4) exhibited more significant inhibitory effects than the positive control cis-platinum toward HL-60and A-549cell lines. Hyperattenin K (7) also showed more obvious cytotoxic activity than the positive control cis-platinum against A-549cell line. Moreover,7showed inhibitory effect against HIV-1virus with EC50and selection index of3.35μM and3.54, respectively.This study on the chemical constituents of Hypericum attenuatum choisy from Dabie mountains of Hubei shows similarities with those reported in literatures and also some PPAPs with intriguing structures have been found, which may benefit much for our understanding of the chemical constituents of Hypericum attenuatum and developing and using this plant.