Crystal structures of 3/4-pyridyl-based thiosemicarbazones and related Cu and Ni coordination compounds.

In this investigation, the crystal structures of the thio-ligands 3-formylpyridine 4-phenylthiosemicarbazone (CHNS, 1) and 4-benzoylpyridine 4-ethylthiosemicarbazone (CHNS, 2), and of two new coordination compounds, chlorido(3-formylpyridine 4-phenylthiosemicarbazone-κS)bis(triphenylphosphane-κP)copper(I) acetonitrile monosolvate, [CuCl(CHNS)(CHP)]·CHCN, 3, and bis(3-formylpyridine 4-ethylthiosemicarbazonato-κN,S)nickel(II), [Ni(CHNS)], 4, are reported. In complex 3, the thio-ligand coordinates in a neutral form to the Cu atom through its S-donor atom, and in complex 4, the anionic thio-ligand chelates to the Ni atom through N- and S-donor atoms. The geometry of complex 3 is distorted tetrahedral [bond angles 99.

Di-2-pyridylketone-N-substituted thiosemicarbazone derivatives of copper(II): Biosafe antimicrobial potential and high anticancer activity against immortalized L6 rat skeletal muscle cells.

The basic aim of this study pertains to developing antimicrobial or anticancer agents based on N, S-donor organic ligands bonded to metals. In the present investigation, di-2-pyridylketone-N-substituted thiosemicarbazone (pytscH-NHR, Chart 2) thio-ligands were reacted with copper(I) halides in organic solvents yielding copper(II) complexes of stoichiometry, [Cu(N,N,S-pytsc-NHR)X] (X = I, R = H, 1; Me, 2; Et, 3; Ph, 4; X = Br, R = H, 5; Me, 6; Et, 7; Ph, 8; X = Cl, R = H, 9; Me, 10; Et, 11; Ph, 12); the formation of Cu probably occurs through a proton coupled electron transfer (PCET) process. Electron spin resonance, ultraviolet-visible spectroscopy and X-ray crystallography (2, 3, 5, 7, 11) supported a distorted square planar geometry of these complexes.