Studies On The Synthesis And Isolation Of Flavonoid And Lignans With Physiological Activity

Flavonoids and Lignans are two kinds of natural botanical constitutes with potential physiological activities, which have attracted more and more research interest . Three major parts are involved in this thesis.The first part deals with the synthetic approach to Benzodihydrofuran derivatives .Four compounds (1)-(4) have been synthesized from primary reactants of vanillin and p-hydroxy benzalhyde, and the key step is finished by biomimetic oxidative coupling of free radicals. All of these synthesized compounds were confirmed by IR, NMR.MS technique.The second part reports the successful synthesis of flavanones conveniently with acid catalyst instead of basic catalyst. Two f lavanones compounds (5) , (6) have been synthesized and determined by means of MS, IR and HNMR spectroscopic methods.if.(6)In the last part a chemical investigation on the orange peel with the application of ultrasonic reactor has led to the isolation of hesperidin in higher yield rate from 0. 8 percent to 2. 15 percent and shorter reaction time from 12 hours to 35minutes, which is confirmed by IR method, and optimum extraction conditions are defined through orthogonal tests.- the rate of calcium hydroxide to orange peel in weight is 4:1, the frequence of ultrasonic reactor is 25KHz, extraction time is 35 minutes, and extraction temperature is 50癈.O--CH,(7)hesperidin...