The synthesis and characterization of six new 2-methylthionicotinate (2-MeSnic) copper(II) monomeric complexes [Cu(2-MeSnic)
2L
2] (L is furo[3,2-c]pyridine—fpy, 2-methylfuro[3,2-c]pyridine—Mefpy, 2,3-dimethylfuro[3,2-c]pyridine—Me
2fpy or benzo[4,5]furo[3,2-c]pyridine—Bfp), [Cu(2-MeSnic)
2(fpy)
2(H
2O)], as well as [Cu(2-MeSnic)
2(CF
3Phfpy)
2(H
2O)
2] (CF
3Phfpy is 2-(3-trifluoromethylphenyl)furo[3,2-c]pyridine) are reported. The characterizations were based on elemental analysis,
infrared, electronic and EPR spectra. The crystal structure of one of the complexes has been determined. The Cu
II atoms of [Cu(2-MeSnic)
2(fpy)
2(H
2O)] are six-coordinated in a highly distorted tetragonal–bipyramidal arrangement by two nitrogen atoms, one from each fpy,
in
trans-positions, by three oxygen atoms of the carboxyl groups of 2-MeSnic ligands (one monodentate, one asymmetrically bidentate),
one axial position being occupied by the oxygen of a water molecule. The antimicrobial effects have been tested on various
strains of bacteria, yeasts and filamentous fungi. A comparison of the IC
50 and MIC values has shown a decrease of inhibition activities of tested compounds in the order: [Cu(2-MeSnic)
2(Bfp)
2] > Bfp > [Cu(2-MeSnic)
2(CF
3Phfpy)
2(H
2O)
2] > [Cu(2-MeSnic)
2(Me
2fpy)
2] > CF
3Phfpy > [Cu(2-MeSnic)
2(Mefpy)
2] > Me
2fpy > [Cu(2-MeSnic)
2(fpy)
2(H
2O)] > [Cu(2-MeSnic)
2(H
2O)]
2 > Mefpy > fpy = 2-MeSnicH = CuSO
4.