2-芳氧甲基苯并咪唑-1-乙酰肼的NMR谱的表征

利用酯3的肼解合成出了8个2-芳氧甲基苯并咪唑-1-乙酰肼(4). 其中4c、4d、4f和4g是新化合物. 利用元素分析、IR 和¹H NMR谱对目标化合物4进行了结构表征. 利用2D NMR谱(包括¹H-¹H COSY、HSQC、HMBC 和 NOESY) 对代表化合物4e进行了¹H 和¹³C NMR的归属及空间结构确定. 通过变温实验和溶剂实验(DMSO-d₆ 和CDCl₃)研究了化合物4e的互变异构. 实验结果表明，室温下，DMSO中，目标化合物4存在着酮式和亚胺醇式这两种异构体的互变，其中酮式占 88.2%~92.6%；而在CDCl₃中，仅以亚胺醇形式存在.

NMR Spectroscopic Characterization of 2-Aryloxymethyl-1H-benzimidazole Acetic Acid Hydrazides

Eight 2-aryloxymethyl-1H-benzimidazole acetic acid hydrazides (4) have been synthesized by hydrazinolysis of the corresponding esters 3. Among them, the compounds 4c, 4d, 4f and 4g are new. The structures of the target compounds 4 were characterized by elemental analysis, IR and ¹H NMR. ¹H and ¹³C NMR signals assignments and spatial structure of representative compound 4e are confirmed by its two-dimensional (¹H-¹H COSY, HSQC, HMBC and NOESY) NMR spectra. The tautomerism of compound 4e were studied by the variable-temperature experiment and solvent experiment (DMSO-d₆ and CDCl₃). The experimental results indicate that the target compounds 4 in DMSO at room temperature exist in the tautomeric keto and imine enol forms, and the dominant keto form isomer consists 88.2%~92.6%, while the imine enol form is the only structure in CDCl₃ at room temperature.