Abstract
Four new complexes have been prepared and characterized from reaction of the tetrapodal Schiff base ligand 1,1,1,1-tetrakis[(3-methoxysalicylaldimino)methyl]methane (H4L) with Cu(II), Ni(II) and Cd(II). X-ray diffraction experiments revealed that 1 ([Cu2L·2H2O]·H2O) and 2 ([Cu2L·2CH3OH]·3H2O) are dinuclear complexes, with the same tetragonal pyramidal coordination geometries around their Cu(II) ions. Complex 3 ([Ni2L]·2H2O) is dinuclear with two square planar Ni(II) ions coordinated to two pairs of the pendant branches of H4L. Complex 4 ([Cd3(HL)2]·3H2O) is a linear trinuclear species with three Cd(II) ions, which were intermolecularly coordinated to three pendant branches of two H4L ligands via an uncommon intermolecular phenoxo oxygen face-sharing mode. The in vitro antimicrobial activities of H4L and its complexes were evaluated against four micro-organisms (Colibacillus, Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus subtilis) using the tube-dilution method. The results revealed that 3 showed good inhibitory activity against the Gram-positive bacteria S. aureus and B. subtilis with MIC values of 62.5 and 31.0 μg mL, respectively.
Funding
This work was supported for financial support from the Teaching Reform and Research Project of the Guizhou University, China [grant number JG 2013014]; The Foundation of Guizhou Province, China [grant number [2014] 7619].
Disclosure statement
No potential conflict of interest was reported by the authors.