SYNTHESIS, STRUCTURE, AND STUDY OF THE BIOLOGICAL ACTIVITY OF Co(II), Ni(II), AND Cu(II) COMPLEXES WITH AN ENAMINEDIONE DERIVATIVE

[Cu(L) 2 ] ( 1 ), [Co(L) 2 ] ( 2 ), [Ni(L) 2 ]·H 2 O ( 3 ) complexes where L is 2-{[(2-methoxyphenyl)amino]methylene}-5,5-dimethyl-cyclohexane-1,3-dionate are synthesized. Single crystals of complexes 1-3 are obtained. According to X-ray crystallographic data, in the Co and Ni complexes, a coordination polyhedron N 2 O 4 is a distorted octahedron, and in the Cu complex, N 2 O 2 is a distorted square. L is a tridentate ligand coordinated by oxygen atoms of carbonyl and methoxy groups as well as the nitrogen atom of the amide group. The cytotoxic properties of 2-{[(2-methoxyphenyl)amino]methylene}-5,5-dimethyl-cyclohexane-1,3-dione and respective complexes are studied on the Hep2 cell line (human laryngeal carcinoma). The compounds are shown to not exhibit cytotoxic properties in the studied concentration range (1-50 μM). Antibacterial, protistocidal, and fungistatic properties of HL, its structural analogue 2-anilinomethylidene-5,5-dimethylcyclohexane-1,3-dione (HL 1 ), and complexes on their base are also studied. The antibacterial activity of HL and [Co(L 1 ) 2 (C 2 H 5 OH) 2 ] against S. aureus , of HL 1 and [Co(L) 2 ] against E. coli is revealed within 25-30% of the activity of reference drugs (ciprofloxacin, furazolidone). The [Ni(L 1 ) 2 (C 2 H 5 OH) 2 ] complex is found to have a pronounced protistocidal activity. Furthermore, the behavior of the [Ni(L) 2 ]·H 2 O complex in phosphate buffered saline is analyzed at storage times t = 0 h, 24 h, 48 h and also in an aqueous solution at different pH values.