Synthesis, Characterization, Crystal Structure and Antimicrobial Activity of Copper(II) Complexes with the Schiff Base Derived from 2-Hydroxy-4-Methoxybenzaldehyde

Molecules

Elena Pahonțu²  Diana-Carolina Ilieș⁵  Sergiu Shova³  Codru↺ Paraschivescu¹  Mihaela Badea⁵  Aurelian Gulea⁴  Tudor Roșu⁵ 

[1] Organic Chemistry Department, Faculty of Chemistry, University of Bucharest, 90-92 Panduri Street, 050663 Bucharest, Romania; E-Mail:;Inorganic Chemistry Department, Faculty of Pharmacy, University of Medicine and Pharmacy “Carol Davila”, 6 Traian Vuia Street, 020956 Bucharest, Romania; E-Mail:;Institute of Macromolecular Chemistry “Petru Poni”, 41A Grigore Ghica Voda Alley, 700487 Iasi, Romania; E-Mail:;Coordination Chemistry Department, Moldova State University, 60 Mateevici Street, 2009 Chisinau, Moldova; E-Mail:;Inorganic Chemistry Department, Faculty of Chemistry, University of Bucharest, 23 Dumbrava Rosie Street, 020462 Bucharest, Romania; E-Mails:

关键词: Schiff bases;    copper(II) complex;    crystal structure;    EPR spectra;    antimicrobial activity;   

DOI  :  10.3390/molecules20045771

来源: mdpi

【 摘 要 】

A novel Schiff base, ethyl 4-[(E)-(2-hydroxy-4-methoxyphenyl)methylene-amino]benzoate (HL), was prepared and structurally characterized on the basis of elemental analyses, ¹H NMR, ¹³C NMR, UV-Vis and IR spectral data. Six new copper(II) complexes, [Cu(L)(NO₃)(H₂O)₂] (1), [Cu(L)₂] (2), [Cu(L)(OAc)] (3), [Cu₂ (L)₂Cl₂(H₂O)₄] (4), [Cu(L)(ClO₄)(H₂O)] (5) and [Cu₂(L₂S)(ClO₄)(H₂O)]ClO₄·H₂O (6) have been synthesized. The characterization of the newly formed compounds was done by IR, UV-Vis, EPR, FAB mass spectroscopy, elemental and thermal analysis, magnetic susceptibility measurements and molar electric conductivity. The crystal structures of Schiff base and the complex [Cu₂(L₂S)(ClO₄)(H₂O)]ClO₄·H₂O (6) have been determined by single crystal X-ray diffraction studies. Both copper atoms display a distorted octahedral coordination type [O₄NS]. This coordination is ensured by three phenol oxygen, two of which being related to the µ-oxo-bridge, the nitrogen atoms of the azomethine group and the sulfur atoms that come from the polydentate ligand. The in vitro antimicrobial activity against Escherichia coli ATCC 25922, Salmonella enteritidis, Staphylococcus aureus ATCC 25923, Enterococcus and Candida albicans strains was studied and compared with that of free ligand. The complexes 1, 2, 5 showed a better antimicrobial activity than the Schiff base against the tested microorganisms.

【 授权许可】

CC BY   
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