Synthesis, characterization and the first crystal structure of the Zn(II) complex of 4,6-O-ethylidine-N-(2-hydroxybenzylidene)-β-D-glucopyranosylamine

Abstract

4,6-O-Ethylidine-N-(2-hydroxybenzylidene)-β-D-glucopyranosylamine (H₃L¹) and N-(5-bromo-2-hydroxybenzylidene-4,6-O-ethylidine-β-D-glucopyranosylamine (H₃L²) molecules possessing a- C-1-N=C(H)- moiety for metal-ion binding were synthesized by condensing the 4,6-O-ethylidene-β-D-glucopyranosylamine with salicylaldehyde or 5-bromosalicylaldehyde. Complexes of these ligands with Zn(II) were isolated and characterized using elemental analysis, FTIR, UV-Vis absorption, NMR spectroscopic and FAB mass spectrometric techniques. The structure of the Zn(II) complex derived from H₃L¹ was established for the first time by a single-crystal X-ray diffraction study. The anomeric nature of the saccharide moiety was established based on ¹H NMR studies and was confirmed by the crystal structure. Further, the structure and binding aspects of the ligand, and the coordination features of this in its Zn(II) complex were derived from the corresponding crystal structure.