Synthesis Of Natural Vitamin E Succinate (α-VES)

A Natural Vitamin E Succinate(a-VES) is a main derivative of natural vitamin E. Recent studies have discovered thatα-VES, excepted acting as a proffer of vitamin E, is an antineoplastic agent. The antineoplastic properties ofα-VES appear to be unique to VE and other derivatives, in this paper,The research covered synthetic technology, quantitative analytical methods,chemical stability,solubility characteristics and the apparent kinetics of catalyst esterification.Vitamin E succinate was synthesized With Vitamin E acetate and succinic anhydride as the materials, 4-Dimethylaminepyridine as catalys ,acetone as the solvent. Using molar ratio of succinic anhydride and Vitamin E, amount of solvent, reaction temperature and reaction time as the test factors, choosing four levels and taking the reaction yield as the test criterion, synthesis process of VES was optimized applying orthogonal design. It is found that the optimum process is molar ratio 3:1, 0.05g of catalyst .solvent volume 10mL(the total weight of Vitamin E and succinic anhydride was 3 grams), reaction temperature 50℃and reaction time 4h. The average yield of the products was 88.57% and the purity was over 96% according to the repeated experiments.A HPLC method for the determination of Natural Vitamin E Succinate is established. A C₁₈ column was used with the mobile phase of methanol-glacial acetic acid(500: 3.2), at the detection wavelength of 285 nm. The calibration curve is linear with concentration of Vitamin E Succinate within range from 100 to 500μg/mL and the average recovery was 99.36%The storage stability and soluble characteristics of Vitamin E Succinate were experimentally determined, Vitamin E Succinate can reduce quickly when it is directly exposed to natural light and heat. The studies showed the solubility of Vitamin E Succinate increased with temperature increasing in aqueous solutions of H₂O, HCl and NaOH. Apperant oil/water partition coefficient in different environment were similar.In the scope of temperature(30℃～60℃)the esterification can be regarded as the second order reaction approximatively. The A and Ea in Arrhenius equation are also determined, which are34.11×10³J·mol^-1 and 1.832×10³mL·mg^-1·h^-1 respectively. So the rate constants of the reaction is k = 1.832×10³ exp(-4012.4K/T).