Lillington J M, Trafford D J, Makin H L
Clin Chim Acta. 1981 Mar 19;111(1):91-8. doi: 10.1016/0009-8981(81)90425-3.
A simple procedure for the esterification of steroid carboxylic acid groups using an acetyl chloride/alcohol reagent has been carefully evaluated. The ease with which these esters can be formed using this reagent depends on the acid and the ester required. C24 bile acids form methyl esters using acetyl chloride/methanol (1:20, v/v) almost instantaneously at 50 degrees C, whereas the C20 aetienic acid studied requires 2 h at 50 degrees C. The formation of isopropyl esters of 5 beta-cholanic acid takes longer (4 h at 50 degrees C) than the formation of n-propyl esters (1 h at 50 degrees C). The identity of various esters fo cholanic acids formed using this reagent have been checked by gas chromatography-mass spectrometry and various other procedures used for the methylation of fatty acids have been examined to establish whether they can be used for the quantitative esterification of bile acids.
一种使用乙酰氯/醇试剂对甾体羧酸基团进行酯化的简单方法已得到仔细评估。使用该试剂形成这些酯的难易程度取决于所需的酸和酯。C24胆汁酸在50℃下使用乙酰氯/甲醇（1:20，v/v）几乎瞬间形成甲酯，而所研究的C20埃替烯酸在50℃下需要2小时。5β-胆烷酸异丙酯的形成比正丙酯的形成（50℃下1小时）所需时间更长（50℃下4小时）。已通过气相色谱-质谱法检查了使用该试剂形成的各种胆烷酸酯的特性，并研究了用于脂肪酸甲基化的各种其他方法，以确定它们是否可用于胆汁酸的定量酯化。
