A series of 5β-cholanic acids labeled with deuterium in the A ring were prepared by exchange labeling of the corresponding ketone by column chromatography on deuterated alumina. Factors affecting yield and labeling efficiency are discussed. 5β-Cholanic acids labeled with 13C in the carboxyl position were prepared by treatment of the corresponding 23-chloro-24-norcholane with sodium cyanide-13C followed by alkaline hydrolysis of the nitrile. The intermediates in the synthesis were characterized by high resolution NMR spectroscopy. Mass spectra are also reported for the 13C labeled products.
通过在氚化氧化铝上进行柱层析,对相应的酮进行交换标记,制备了一系列在 A 环中用
氘标记的 5β-cholanic 酸。本文讨论了影响产率和标记效率的因素。用
氰化钠-13C 处理相应的 23-
氯-24-正胆烷,然后碱
水解腈,制备了在羧基位置标记 13C 的 5β-Cholanic 酸。合成过程中的中间产物通过高分辨率核磁共振光谱进行了表征。同时还报告了 13C 标记产物的质谱图。