Affiliation:
1. Instituto de Química, Universidad Nacional Autonomous University of Mexico, Mexico City 04510, Mexico
Abstract
Curcuminoids are widely studied due to their well-recognized therapeutic properties. These molecules are often derivatized with metals, producing their corresponding homoleptic metal complexes. Numerous crystal structures of homoleptic symmetric curcuminoids with physiologically essential metals are known, although the literature lacks reports of homoleptic metal complexes of unsymmetric curcuminoids (or hemi-curcuminoids) as ligands. Three unknowns must be solved when an unsymmetric curcuminoid ligand is reacted with a metal ion: (a) the degree of coordination (MLn); (b) the spatial geometry; and (c) the conformational nature (syn or anti) of the complex. Herein, we report the structure of the anti-isomer of the Zn complex of the hemi-curcuminoid 5-hydroxy-1-(4-methoxyphenyl)hexa-1,4-dien-3-one. While the NMR shows only one set of signals for this homoleptic complex, the unambiguous stereochemistry was established through single-crystal X-ray diffractometry, revealing an anti-hexacoordinated octahedral ML2 structure.
Reference41 articles.
1. Synthesis and Biological Evaluation of Unsymmetrical Curcumin Analogues as Tyrosinase Inhibitors;Jiang;Molecules,2013
2. New Synthetic Glucosyl-Curcuminoids, and Their 1H and 13C NMR Characterization, from Curcuma longa L.;Saladini;Plant Foods Hum. Nutr.,2009
3. Study of the Keto-Enolic Equilibrium in Structures of Synthetic Curcuminoids by Means of RMN and X Rays Diffraction;Rev. Cuba. Química,2013
4. Cytotoxic Activity of Curcuminoids and Curcuminoid Analogues Against Human Oral Cancer KB Cells;Haritakun;SDU Res. J.,2016
5. Synthesis, DNA-Binding, and Cytotoxic Studies on Three Copper(II) Complexes of Unsymmetrical Synthetic Analogues of Curcumin;Deepthi;J. Coord. Chem.,2016