Abstract The present work reports the syntheses, crystal structures and spectroscopic characterization of later first-row transition metal complexes of hydroxyacetone derived N4-methyl substituted thiosemicarbazone. The molecular structures of Co(II) and Ni(II) complexes are determined by single crystal X-ray diffraction method. The crystal structures reveal that the Co(II) and Ni(II) complexes have crystallized in monoclinic and triclinic crystal systems with C2/c and P-1 space groups, respectively. The ligand, 1-(1-hydroxypropan-2-ylidene)-N4-methylthiosemicarbazone ligates in a neutral, SNO tridentate fashion to the central metal ions. The numerous physicochemical investigations carried out to the synthesized complexes disclose the metal to ligand stoichiometry to be 1:2 in Co(II), Ni(II) and Zn(II) complexes whereas 1:1 in Cu(II) complex. The ligand environment forms a distorted octahedral geometry around Co(II), Ni(II) and Zn(II) metal centers, while square pyramidal geometry over Cu(II) ion. The in vitro antitubercular results against Mycobacterium tuberculosis affirm that the synthesized compounds are four-fold more active than the standard drug, Streptomycin and two-fold more active than the other two standards used, Pyrazinamide and Ciprofloxacin.

中文翻译：

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羟基丙酮衍生的 N4-甲基取代氨基硫脲：后来的第一行过渡金属配合物的合成、晶体结构和光谱表征

摘要 目前的工作报告了羟基丙酮衍生的 N4-甲基取代氨基硫脲的第一排过渡金属配合物的合成、晶体结构和光谱表征。Co(II)和Ni(II)配合物的分子结构通过单晶X射线衍射法确定。晶体结构表明 Co(II) 和 Ni(II) 配合物分别在具有 C2/c 和 P-1 空间群的单斜和三斜晶系中结晶。配体 1-(1-羟基丙-2-亚基)-N4-甲基缩氨基硫脲以中性 SNO 三齿方式与中心金属离子连接。对合成的配合物进行的大量物理化学研究表明，Co(II)、Ni(II) 和 Zn(II) 配合物中金属与配体的化学计量比为 1:2，而在 Cu(II) 配合物中为 1:1。配体环境在 Co(II)、Ni(II) 和 Zn(II) 金属中心周围形成扭曲的八面体几何形状，而在 Cu(II) 离子上形成方形金字塔几何形状。针对结核分枝杆菌的体外抗结核结果证实，合成的化合物比标准药物链霉素的活性高四倍，比其他两种使用的标准药物吡嗪酰胺和环丙沙星的活性高两倍。