Synthesis, Structure, and Biological Assays of Novel Trifluoromethyldiazepine–Metal Complexes

ROCHA, MARIANA; ECHEVERRÍA, GUSTAVO A.; PIRO, OSCAR E.; JIOS, JORGE J.; MOLINA, ROCÍO D. I.; ARENA, MARIO E.; ULIC, SONIA E.; GIL, DIEGO M.

AUSTRALIAN JOURNAL OF CHEMISTRY

CSIRO PUBLISHING

Lugar: Collingwood; Año: 2020 vol. 73 p. 49 - 60

0004-9425

A new series of Cu(II), Ni(II), Co(II) and Mn(III) complexes have been synthesized from (6Z)-6-(7-trifluoromethyl-1,2,3,4-tetrahydro-5H-1,4-diazepin-5-ylidene)cyclohexa-2,4-dien-1-one (HDZP) ligand. These complexes were characterized by elemental, spectral (IR and UV-Vis) and thermal analysis. The crystal structure of Cu-DZP was solved by X-ray diffraction methods. The complex crystallizes in the monoclinic P21/c space group, with two molecules per unit cell. The crystal lattice is stabilized by different intra and intermolecular interactions. Hirshfeld surface analysis was employed to obtain additional insight into interactions that are responsible for the crystal packing. Quantitative examination of the fingerprint plots revealed, among other, the dominating participation of H???H and H???X (X= O, F) interactions in the crystal packing. In addition, C-H???chelate ring (CR) and C-H???π interactions are described and evaluated using DFT calculations. The antibacterial and inhibition of the main bacterial resistant mechanism, the biofilm, of metal complexes and free ligand were tested. Mn-DZP was the most active complex against Pseudomonas aeruginosa biofilm formation with an inhibition of 40%. However, none of the complexes inhibit more than 25% of the Gram negative bacteria microbial development. The most significant result was the bactericidal effect of [Co(DZP)2(H2O)2]?2H2O against the Gram positive bacteria, Staphylococcus aureus that inhibit the bacterial development and reduce significantly the biofilm formation at low concentration.