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Updated: Aug 30, 2026

Structure and Coordination Determination of Peptide-metal Complexes Using 1D and 2D 1H NMR
Published on: December 16, 2013
The crystal structure of a novel copper(II) complex with asymmetric ligand derived from l-histidine
Patrick Deschamps1, Prasad P Kulkarni, Bibudhendra Sarkar
1Department of Structural Biology and Biochemistry, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada.
Abstract:
The crystal structure of a novel copper(II) complex with a potentially hexadentate Schiff base ligand derived from l-histidine has been solved by a single-crystal X-ray diffraction method at pH 7.4. The copper(II) ion is coordinated asymmetrically by a tetradentate ligand with the amino and imidazole imido nitrogen atoms on one side versus imino nitrogen and carboxylate oxygen atoms on the other side in a distorted square-planar geometry. The formation of an infinite chain through carboxylate coordination is observed. The novel ligand is obtained by the reaction between the l-histidine molecules coordinated to copper(II) and 4-hydroxy-4-methylpentan-2-one formed by aldol condensation of acetone. This complex provides insights into a possible structural arrangement between copper(II) and l-histidine which is physiologically important and abundantly present in biological systems.
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