Diastereoisomers of oxazolam (2R-cis, 2R-trans, 2S-cis, and 2S-trans isomers) were resolved and assigned by high-performance liquid chromatography (HPLC). By means of HPLC the cis/trans isomerization rates of oxazolam in some organic solvents could be measured, although such rate measurements had previously been attempted only by an nuclear magnetic resonance (NMR) method and it was reported that in most organic solvents the isomerization was too fast to allow the rates to be measured. In some cases (depending on the lot number of the solvent), rapid isomerization was observed in chloroform-d (the ratio of cis isomer to trans isomer (2 : 3) did not change with time, that is, the isomerization was at equilibrium immediately after dissolution of oxazolam in the CDCI3). This fast isomerization was suggested to be catalyzed by an acid contaminant, since the iminium intermediate of oxazolam was detected in the reaction solution by fluorescence spectroscopy.
通过高效
液相色谱法(HPLC)解析并确定了
恶唑仑的消旋异构体(2R-cis、2R-trans、2S-cis和2S-trans异构体)。通过HPLC可以测量
恶唑仑在某些有机溶剂中的顺式/反式异构化率,尽管此前仅通过核磁共振(NMR)方法尝试过测量这种速率,并且有报道称在大多数有机溶剂中异构化速度太快,无法测量速率。在某些情况下(取决于溶剂的批号),在
氯仿-d中观察到快速异构化(顺式异构体与反式异构体的比率(2:3)不会随时间变化,也就是说,在
恶唑仑溶解在C
DCI3中后,异构化立即达到平衡)。这种快速异构化被认为是由一种酸性污染物催化的,因为在反应溶液中通过荧光光谱检测到了
恶唑仑的亚
氨基中间体。