Bimetallic complexes constructed from asymmetrical N,N'-bis(substituted)-oxamide: cytotoxicities, and reactivities towards DNA and protein.

A new asymmetrical N,N'-bis(substituted)oxamide ligand, N-(5-chloro-2-hydroxyphenyl)-N'-[3-(dimethylamino)propyl]oxamide (C(13)H(18)N(3)O(3)Cl·H(2)O, H(3)L) and its two binuclear complexes [Cu(2)L(H(2)O)(bpy)](ClO(4))·CH(3)OH (1) and [Ni(2)L(bpy)(2)](ClO(4)) (2) [bpy = 2,2'-bipyridine] have been synthesized and characterized by X-ray single-crystal diffraction. In the crystal structure, H(3)L adopting a transoid conformation occurs as a neutral molecule linked with a water molecule by an intermolecular hydrogen bond. In the two complexes, the cis-L(3-) ligand bridges two metal ions with the corresponding separations of 5.2032(15) Å (1) and 5.2466(7) Å (2), respectively. In vitro cytotoxic activities, and the reactivities of the three compounds towards DNA and protein are investigated.