Study On The Total Synthesis Of Hypericin

Hypericin is a dianthraquinone constituent of plants of the Hypericum genus. In 1911, hypericin was named by Cerny. In 1957, hypericin was extracted from Hypericum perforatum L. Hypericum perforatum L. is commonly known as St. John's wort ,which is a medicinal plant traditionally used, both externally and internally, in all Europe for many pathologies. Hypericin is a characteristic constituent of St. John's wort. The molecule can also be synthesized for example by the condensation of two derivatives of anthraquinone.The interest in the hypericin is a result of the discovery of its pharmaceutical potential Such as, (1)its antiviral activities, especially anti-HIV property, inhibiting action on FMDV, treatment on leucocythemia, improving the quality of blood produces, and killing the virus of bird flu. (2)its antidepressant effect. (3)its anti-tumor activity. Besides, hypericin has long been used in traditional medicine, for example in the treatment of wound healing , diarrhea, tummy bug, toothache.In this dissertation, the total syntheses of hypericin in literature were reviewed, and several feasible ways were designed. Of those ways, the second way of using the original raw material, methyl 3,5-dimethoxy benzoate, was adopted. Due to the limitation of time and other factors , only the intermediate, 3,5-Dimethoxy-phthalic anhydride was synthesized through hydroxyalkylation, transesterification, hydrolysis, oxidation, decarboxylation and dehydration reactions, and the mechanisms of every reactions were investigated. In addition, the application and foreground of hypericin were viewed.The structure of the synthetic products were characterized by differential scanning calorimetry(DSC) , infrared(IR) , mass spectra(MS) and ~1H Nuclear Magnetic Resonance(NMR). The results indicated that the structures and properties of the products conformed to the design requirement, and the yield of every reaction was more than 90%, this can prognosticate the designed total synthesis method of hypericin using methyl 3,5-dimethoxy benzoate as the beginning material, was practical and effective.