Synthesis, Crystal Structure, and Antibacterial Activity of N′-(2-hydroxy-3-methoxybenzylidene)isonicotinohydrazide and Its Dinuclear Manganese(II) Complex with N′-(2-hydroxy-3-methoxybenzylidene)isonicotinohydrazide

Abstract

A phenolate oxygen bridged dinuclear manganese(2) complex [Mn₂Cl₂L₂(OH₂)₂]·2CH₃OH (2) was obtained from N′-(2-hydroxy-3-methoxybenzyl-idene)isonicotinohydrazide (HL, 1) and MnCl₂. Both the ligand HL and the complex were characterized by IR spectra and single-crystal X-ray diffraction. The crystal of 1 crystallizes in the monoclinic space group P2₁/c, with a = 7.6711(2), b = 16.2568(4), c = 10.8787(3) Å, β = 110.428(2)°, V = 1271.34(6) ų, Z = 4. The crystal of 2 crystallizes in the monoclinic space group P2₁/n, with a = 9.4984(8), b = 12.1361(12), c = 15.3414(15) Å, β = 96.269(5)°, V = 1757.9(3) ų, Z = 2. The ligand HL coordinates to the Mn atom through the deprotonated phenolate O atom, the imine N atom, and the carboxy O atom. The Mn atom is in a pentagonal bipyramidal coordination. The antibacterial activity of the complex and the ligand against the bacteria Staphylococcus aureus, Bacillus anthracis, Pseudomonas aeruginosa, and Streptococcus agalactiae was investigated.

Keywords:

• antibacterial activity
• crystal structure
• manganese
• Schiff base
• synthesis