Separation Of Chrysophanol And Physcione And Microwave-assisted Synthesis Of Rhein

Rhubarb is an important traditional Chinese medicine. The compounding preparation whose main constituent is rhubarb, is widely applied in clinic of today's medicine, with good effect. The Chrysophanol and Physcione in natural Rhubarb have resemble structure and close characters, so they were usually extracted from Rhubarb together. After comparison of several separation methods, pH grads extraction method was adopted, and Chrysophanol and Physcione was separated well using a proper solvent and optimal pH gradient solution. The result showed that when the extracting condition is 20 mg mixture dissolved in 50 ml Ethyl acetate and 0.1% concentration of NaOH extract liquid, the purity of obtained Chrysophanol is up to 95.06%. The operation of pH grads extraction method is very simple and could carry out repetitive manufacturing and industrialization production, furthermore, recycling use of solvent and material could decrease cost.Rhein is a broad spectrum antibiotic with littile side-effect, possessing some degree of curative effect to diabetes, nephropathy, obesity, hyperlipidemia, hypertension. However its content is poor in natural Rhubarb, the cost will be very high to extract it from traditional Chinese medicine, and its complete synthesis route is too complex. The content of Chrysophanol in natural Rhubarb is rich, but its effect is single, and activity is weaker than Rhein. Seeing that Chrysophanol has the same basic parent structure with Rhein, Rhein was synthesized through acetylation, oxidation and deacetylation reaction taking Chrysophanol as raw material. This prepared method takes on high economic value, because the Chrysophanol in Rhubarb was good used, and the sythesis route is simple. During the procces of synthesis of Diacerein, reaction condition was optimized by Orthogonal experimental design and single factor experiment. The final production rate was 52.15%. The synthesis process was real-time monitored and detected by TLC and HPLC. The product was validated by FTIR and NMR.In addition, Microwave heating is prompt and takes on selectivity for interaction with material directly. Microwave induced organic reaction takes on some advantages, for example, enhancing rate of reaction, decrease byproduct, improving yield, selecting reaction route and carrying out free-solvent course. The Microwave-assisted synthesis of Diacerein was researched. The result showed that Microwave heating is more effective and the rate of reaction by Microwave heating is more twice compared with traditional method. In addition to, The reaction still can be carried out with the high convert ratio under microwave heating.