Synthesis, Physico-chemical Characterization, Crystal Structure and Influence on Microbial and Tumor Cells of Some Co(II) Complexes with 5,7-Dimethyl-1,2,4-triazolo[1,5-a]pyrimidine.

Three complexes, namely [Co(dmtp)₂(OH₂)₄][CoCl₄] (), [Co(dmtp)₂Cl₂] () and [Co(dmtp)₂(OH₂)₄]Cl₂∙2H₂O () (dmtp: 5,7-dimethyl-1,2,4-triazolo[1,5-]pyrimidine), were synthesized and characterized by spectral (IR, UV-Vis-NIR), and magnetic measurements at room temperature, as well as single crystal X-ray diffraction. Complex () crystallizes in monoclinic system (space group 2/c), complex () adopts an orthorhombic system (space group bca), and complex () crystallizes in triclinic system (space group P1). Various types of extended hydrogen bonds and π-π interactions provide a supramolecular architecture for all complexes. All species were evaluated for antimicrobial activity towards planktonic and biofilm-embedded microbial cells and influence on HEp-2 cell viability, cellular cycle and gene expression.