7-去氢胆甾乙酸酯的合成研究

研究7-去氢胆甾乙酸酯的合成方法，以胆甾乙酸酯为原料，经过上溴和脱溴反应制得7-去氢胆甾乙酸酯，用气相色谱法检测7-去氢胆甾乙酸酯的含量，通过7-去氢胆甾乙酸酯的质量变化以及计算从胆甾乙酸酯至7-去氢胆甾乙酸酯的收率来考察上、脱溴反应的选择性。对偶氮化合物和过氧化物化合物自由基引发剂进行选择，最终确定最合适的ABV引发剂，使上、脱溴反应的选择性得到提高。此外．还对上溴反应温度、上溴反应时间以及上溴引发剂的用量进行探讨，确定最佳反应条件。结果表明，脱溴物中7-去氢胆甾乙睃酯的含量由60％提高至70％，从胆甾乙酸酯至7-去氢胆甾乙酸酯的收率由56％提高至69％以上。

Study on synthesis of the 7-dehydrocholesteryl aetate

The synthesis of the 7-dehydrocholesteryl aerate is discussed in the article. 7-Dehydrocholesteryl acetate is prepared by bromination the cholesteryl aetate and debromination then. Content of the 7-dehydrocholesteryi acetate is detected by the gas chromatography. The selectivites of the bromination and debromination are appraised by the change of the quality of the 7-dehydrocholesteryl acetate and the yield of the 7-dehydrocholesteryi acetate calculated from the cholesteryi aetate. The ultimate result of Chesen evocator is ABV, and the selectivites of bromination and debromination are advanced, Furthermore, the reaction temperature, the time and the dosage of evocator on hromination are discussed, the best conditions of reaction is confirmed. The result indicated, the content of 7-dehydrocholesteryi acetate from 60% to 70%, the overall yield of 7-dehydrocholesteryl acetate based on cholesteryl aetate from 56% to 69%.