Methyl 2-(3,4-dichlorobenzoyl)-1-methylhydrazinecarbodithioate, C10H10Cl2N2OS2, (F1), butyl 2-(3,4-dichlorobenzoyl)-1-methylhydrazinecarbodithioate, C13H16Cl2N2OS2, (F2), and 3,4-dichloro-N-(2-sulfanylidene-1,3-thiazinan-3-yl)benzamide, C11H10Cl2N2OS2, (F3), were studied by X-ray diffraction to test our hypothesis that planarity of aryloylhydrazinedithiocarbazic acid esters is a prerequisite for tuberculostatic activity. All compounds examined in this study are inactive and nonplanar due to twists along two specific bonds in the central frame of the molecules. The significant twist at the N—N bond, with an C—N—N—C(S) torsion angle of about 85°, results from repulsion caused by a methyl substituent at the N′ atom of the hydrazide group. The other twist is that within the benzoyl group at the C(O)—Ph bond,i.e.the N—C(=O)—C(phenyl)—C torsion angle: the values found in the studied structures (25–30°) are in agreement with those observed in other compounds containing a similar fragment. As some nonplanar benzoyl derivatives are active, it seems that planarity of the hydrazinedithioate fragment is more important for tuberculostatic activity than planarity of the aryloyl group.
用 X 射线衍射法研究了 2-(3,4-二氯苯甲酰基)-1-甲基肼二硫代碳酸甲酯 C10H10Cl2N2OS2(F1)、2-(3,4-二氯苯甲酰基)-1-甲基肼二硫代碳酸丁酯 C13H16Cl2N2OS2(F2)和 3,4-二氯-N-(2-亚硫酰-1、3-噻嗪南-3-基)苯甲酰胺(C11H10Cl2N2OS2,(F3))进行了 X 射线衍射研究,以验证我们的假设,即芳基肼二硫代咔嗪酸酯的平面性是产生抗结核活性的先决条件。本研究中考察的所有化合物都不具有活性,并且由于分子中心框架中两个特定键的扭曲而不具有平面性。N-N 键处的扭转非常明显,C-N-N-C(S)扭转角约为 85°,这是由于酰肼基团 N′原子上的甲基取代基引起的斥力所致。另一种扭转是苯甲酰基内部 C(O)-Ph 键处的扭转,即 N-C(=O)-C(苯基)-C 扭转角:研究结构中发现的扭转角值(25-30°)与在其他含有类似片段的化合物中观察到的扭转角值一致。由于一些非平面苯甲酰基衍生物具有活性,因此肼基二硫代酸酯片段的平面性似乎比芳基的平面性对抗结核活性更为重要。