A novel phenolato and acetato bridged trinuclear Ni(II) complex [ Ni3L2 ] was synthesized by the reaction between the amino acid Schiff base, N- o -vanillylidene- l -histidine( L ) and Ni(OAc)2·2H2O. Single crystal X-ray analysis reveals that the trinuclear structure of Ni3L2 is built by linking two terminal NiN2O4 cores with one NiO6 centre core (NiN2O4⋯NiO6⋯NiN2O4) and each Ni(II) ion exists in an octahedral environment. Variable-temperature magnetic susceptibility data represent the antiferromagnetic interactions of the Ni3L2 mediated by a single Ni-O-Ni bridge. The bond length and bond angles around each terminal nickel centre match the nickel centre in urease enzyme of native bacteria Klebsiella aerogenes , Bacillus pasteurii and Helicobacter pylori. The catalytic activity of Ni3L2 on the hydrolysis of urea into ammonia and carbon dioxide was established by the absorption spectral method. The urea binding propensity of the nickel complex Ni3L2 was compared with jack bean urease by using molecular docking studies.
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