Complexes based N , N -donors (2,2′-bipyridyl & 2-(2-aminophenyl)benzimidazole); Synthesis, characterization, DNA interaction and toxicity assessment against Chlorella vulgaris microchlorophyte; X-ray crystal structure of [Zn(bpy) 3 )]Cl 2

作者：Neveen A. Annan; Ian S. Butler; Yehia A. Osman; Mervat H. Hussein; Bertrand J. Jean-Claude; Eman M. Saad; Sahar I. Mostafa

来源：Inorganica Chimica Acta, 2020, 512: 119885.

DOI：10.1016/j.ica.2020.119885

• Complexes
• Zinc
• HAPB
• Spectra
• DNA
• Stoichiometry

The syntheses of some N , N -donors, 2,2′-bipyridyl (bpy) and 2-(2-aminophenyl)benzimidazole (HAPB) complexes are reported. The structures of the complexes are discussed on the bases of their IR, NMR ( 1 H, 13 C, 31 P), UV–Vis, and EI and maldi-mass spectra, elemental analyses, molar conductivities and TGA behaviour. HAPB coordinates to the central metal ions in neutral monodentate {[Au(HAPB)Cl 3 ], cis -[MoO 2 (HAPB)(DMF)Cl 2 ], [Pd(HAPB)(H 2 O)Cl 2 ], [M(HAPB)(PPh 3 )Cl 2 ] and [Pd(bpy)(HAPB)Cl]Cl} or bidentate {[Zn(HAPB) 2 ](ClO 4 ) 2 , [Zn(PPh 3 )(HAPB)Cl 2 (H 2 O)], [Ag(L)(HAPB)]NO 3 (L = bpy, PPh 3 ), [M(HAPB)Cl 2 ] (M(II) = Pd, Pt), [Rh(HAPB) 2 Cl 2 ]Cl and [Rh(PPh 3 )(HAPB)Cl]Cl 2 } fashion, via the imidazole N- atom or both amino N- and imidazole N -atoms, respectively. The X-ray crystal structure of the complex, [Zn(bpy) 3 )]Cl 2 , has been determined. It has been crystallized in a monoclinic lattice with space group symmetry P 2/n . The Zn(II) ion is coordinated in a distorted octahedral geometry by the two nitrogen atoms of three bpy moieties in the expected neutral bidentate fashion. The stoichiometries and the formation constants of Pd(II), Pt(II), [M(L)Cl 2 ] (L = bpy, 2PPh 3 ) complexes have been determined using both Job’s and the molar ratio methods. The DNA-binding constants of some of the complexes have been calculated based on UV–vis spectroscopy. The results indicate intercalative CT-DNA binding in view of their hypochromism and low-to-moderate binding abilities. The DNA binding abilities of the complexes follow the order [Pd(PPh 3 )(HAPB)Cl 2 ] > [Pt(HAPB)Cl 2 ] > [Pd(HAPB)(H 2 O)Cl 2 ] > [Pd(HAPB)Cl 2 ], which may result from steric hindrance around the metal ions comes from HAPB with bpy or PPh 3 chelates. Moreover, the toxicity of HAPB and its Pd(II) complexes against the microchlorophyte (Chlorella vulgaris ) have been assessed.