【摘要】 <正> 用催化通²H₂（³H₂）的方法对合双键的前身物进行加²H₂（³H₂）反应以制备相应的标记化合物,理论上应是严格定位的。但实际上标记原子在分子中的分布常较复杂,对氚的核磁共振分析（TNMR）已发表若干实例。本文介绍用气相色谱-质谱联用仪（GC-MS）测定²H-亮氨酸的质谱图,分析其中²H原子分布的结果。更多还原

【Abstract】 DL-(4,5-2H)-leucine was prepared by catalytic deuteration of its double-bond pre- cursor. Its trifluoroacetyl butanolic ester derivative was prepared and the deuterlum content was estimated by GC-MS. Analysis of the m/e = 182 fragment by Biemann’s method revealed that the 2H content varied from 0 to 6. The percentage of molecules containing no deuterium atom was 16.4, indicating that the abundance of labelled molecules (regardless of the number of deuterium atoms in each molecule) was 83.6%. Calculated from the intensity of the fragments m/e = 182, 153, 140 by Biemann’s method the abundances of labelled atoms at different C positions of the leucine molecule was: C1-0%; C2-2.9%; C3-22.5%; C4, C5, C6-54.2% (average).更多还原