SYNTHESIS, CHARACTERIZATION AND CRYSTAL STRUCTURE OF A POLYMERIC SILVER(I) COMPLEX WITH CYTOTOXIC PROPERTY

A new polymeric silver(I) complex, [Ag 2 (L1) 2 (L2)(OH 2 )] n , was obtained by the reaction of 3-aminopyrazine-2-carboxylic acid (HL1), 2-amino-5-methylpyridine (L2) and silver oxide in aqueous ammonia. The complex was characterized by elemental analysis, IR spectra and single crystal X-ray determination. The smallest repeat unit contains a [Ag 2 (L1) 2 (L2)(OH 2 )] moiety. The Ag···Ag distance is 7.490(2) A. One Ag atom is coordinated by three pyrazine N and two carboxylate O atoms from four L1 ligands, forming a square pyramidal coordination, and the other one is coordinated by one pyrazine N and one carboxylate O atoms from a L1 ligand, one pyridine N atom from a L2 ligand, and one water O atom, forming a square planar geometry. In the crystal structure of the complex, the dinuclear silver moieties are linked through L1 ligands, to form 1D chains along the x-axis direction. The chains are further linked through intermolecular hydrogen bonds in the y- and z-axis directions, forming a 3D network. In addition, there are π···π interactions among the chains. The complex showed effective cytotoxic property on human lung cancer cell line A549.