Gold complexes with thiosemicarbazones: reactions of bi- and tridentate thiosemicarbazones with dichloro[2-(dimethylaminomethyl)phenyl-C 1,N ]gold(III), [Au(damp-C 1,N )Cl2]
作者:Ulrich Abram、Kirstin Ortner、Ronald Gust、Klaus Sommer
DOI:10.1039/a908712e
日期:——
Dichloro[2-(N,N-dimethylaminomethyl)phenyl-C1,N]gold(III), [Au(damp-C1,N)Cl2] (1), reacts with salicylaldehyde thiosemicarbazone (H2saltsc), vanilline thiosemicarbazone (Hvantsc), N-methylpyrrole aldehyde thiosemicarbazone (Hmepyrtsc), pyridoxal methylthiosemicarbazone (H2pydoxmetsc), 2-diphenylphosphinobenzaldehyde thiosemicarbazone (HPtsc) or variously substituted acetylpyridine thiosemicarbazones (HapRtsc; R = H, Me, Ph) with cleavage of the Au–N bond and protonation of the dimethylamino group. Compounds of general formulae [Au(Hdamp-C1)Cl(L)]+ (L = Hsaltsc−, vantsc−, mepyrtsc−), [Au(Hdamp-C1)Cl(L)]2+ (L = H2pydoxmetsc) or [Au(Hdamp-C1)(L)]2+ (L = Ptsc−, apRtsc−, R = H, Me, Ph) have been isolated and characterized. The presence of the σ-bonded 2-(dimethylaminomethyl)phenyl ligand is mandatory to prevent reduction of the gold(III) centre. The crystal structures of [Au(Hdamp-C1)Cl(Hsaltsc)](PF6) (3a), [Au(Hdamp-C1)Cl(mepyrtsc)]Cl (3c), [Au(Hdamp-C1)Cl(H2pydoxmetsc)]Cl2·MeOH (4), [Au(Hdamp-C1)(apPhtsc)]Cl2·2 MeOH (5c) and [Au(Hdamp-C1)(Ptsc)]Cl2· 1.5MeOH (6) have been elucidated, showing the gold atoms in distorted square-planar co-ordination environments.
The potentially O,N,S-tridentate ligands H2saltsc and H2pydoxmetsc co-ordinate in a bidentate fashion and do not incorporate the OH groups in the chelating framework, whereas HapRtsc or HPtsc co-ordinate in a tridentate manner. Generally, one or more hydrogen atoms of the heterocyclic ligands and/or the NMe2H+ group form hydrogen bridges in the solid state structures. The preliminary results of antiproliferation tests on tumor cells demonstrate the considerable cytotoxicity of these new gold complexes.
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二氯[2-(N,N-二甲氨基甲基)苯-C1,N]金(III), [Au(damp-C1,N)Cl2] (1), 与水杨醛缩氨基硫脲(H2saltsc), 香草醛缩氨基硫脲(Hvantsc), N-甲基吡咯醛缩氨基硫脲(Hmepyrtsc), 吡哆醛缩甲基氨基硫脲(H2pydoxmetsc), 2-二苯基膦基苯甲醛缩氨基硫脲(HPtsc)或者各种取代的乙酰吡啶缩氨基硫脲(HapRtsc; R = H, Me, Ph)反应, 导致Au–N键断裂并使二甲氨基质子化. 根据通式[Au(Hdamp-C1)Cl(L)]+(L = Hsaltsc−, vantsc−, mepyrtsc−), [Au(Hdamp-C1)Cl(L)]2+(L = H2pydoxmetsc), 或者[Au(Hdamp-C1)(L)]2+(L = Ptsc−, apRtsc−, R = H, Me, Ph)分离并表征得到化合物. 为了防止金(III)中心的还原, 必须存在σ键合的2-(二甲氨基甲基)苯配体. 通过测定[Au(Hdamp-C1)Cl(Hsaltsc)](PF6) (3a), [Au(Hdamp-C1)Cl(mepyrtsc)]Cl (3c), [Au(Hdamp-C1)Cl(H2pydoxmetsc)]Cl2·MeOH (4), [Au(Hdamp-C1)(apPhtsc)]Cl2·2 MeOH (5c)和[Au(Hdamp-C1)(Ptsc)]Cl2· 1.5MeOH (6)的晶体结构, 发现金原子处于扭曲的平面四边形配位环境.
潜在的O,N,S-三齿配体H2saltsc和H2pydoxmetsc以二齿的形式配位, 没有把羟基包含在螯合骨架中, 然而HapRtsc或HPtsc以三齿的形式配位. 通常, 杂环配体的一个或者多个氢原子和/或者NMe2H+形成氢键出现在固态结构中. 对肿瘤细胞的抗增殖试验的初步结果表明这些新金配合物具有较大的细胞毒性.