l-Tyrosinatonickel(II) Complex: Synthesis and Structural, Spectroscopic, Magnetic, and Biological Properties of 2{[Ni(l-Tyr)2(b

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• 作者：Agnieszka Wojciechowska ; Anna G膮gor ; Marek Duczmal ; Zbigniew Staszak ; Andrzej Ozarowski
• 刊名：Inorganic Chemistry
• 出版年：2013
• 出版时间：April 15, 2013
• 年：2013
• 卷：52
• 期：8
• 页码：4360-4371
• 全文大小：551K
• 年卷期：v.52,no.8(April 15, 2013)
• ISSN：1520-510X

文摘

The complex 2{[Ni(l-Tyr)₂(bpy)]}路3H₂O路CH₃OH [1, where l-Tyr = l-tyrosine; bpy = 2,2鈥?bipyridine (2,2鈥?bpy)] was obtained in crystalline form and characterized by X-ray and spectroscopic (FT-IR, NIR鈥搗is鈥揢V, and HFEPR) and magnetic methods. The complex crystallized in the hexagonal system with a = b = 12.8116(18) 脜, c = 30.035(6) 脜, and space group P3₂2₁. The six-coordination sphere around the Ni²⁺ ion is formed by two N and two O l-tyrosinato atoms and completed by two N atoms of the 2,2鈥?bpy molecule. Neighboring [Ni(l-Tyr)₂(bpy)] units are joined via weak hydrogen bonds, which create a helical polymeric chain. The coordinated atoms form a strongly distorted cis-NiN₂N₂鈥睴₂ octahedral chromophore. The solid-state electronic spectrum of complex 1 was analyzed assuming D_2h symmetry, and the observed bands were assigned to ³B_1g 鈫?³A_g, ³B_1g 鈫?³B_3g, ³B_1g 鈫?³B_2g, ³B_1g 鈫?³B_3g, ³B_1g 鈫?³B_1g, and ³B_1g 鈫?³B_2g transitions for the I and II d鈥揹 bands, respectively. The crystal-field parameters found for D_2h symmetry are Dq = 1066 cm^鈥?, Ds = 617 cm^鈥?, Dt = 鈭?3 cm^鈥?, B₂₂ = 7000 cm^鈥?, and Racah B = 812 cm^鈥?. Magnetic studies revealed the occurrence of hydrogen-bonded metal pairs. The spin Hamiltonian parameters D = 鈭?.262 cm^鈥? and E = 鈭?.1094 cm^鈥?, determined from high-field, high-frequency electron paramagnetic resonance spectra, together with a weak antiferromagnetic exchange parameter J = 鈭?.477 cm^鈥?, allowed us to reproduce the powder magnetic susceptibility and field-dependent magnetization of the complex. The biological activity of 1 has been tested by using the Fusarium solani, Penicillium verrucosum, and Aspergillus flavus fungi strains and Escherichia coli, Pseudomonas fluorescens, Serratia marcescens, and Bacillus subtilis bacterial strains.