Mechanochemical Synthesis of Biologically Active Transition Metal Complexes of 1H-4,4,6-Trimethyl-3,4-dihydropyrimidine-2-thione

Abstract

A new series of metal complexes using 1H-4,4,6-trimethyl-3,4-dihydro-2-pyrimidinethione (HTMPT) ligand were synthesized mechanochemically and also evaluated for antibacterial and DNA photocleavage potential. Complexes of 1H-4,4,6-trimethyl-3,4-dihydro-2-pyrimidinethione (HTMPT) [M(tmpt)2(H2O)n] (M = Cu2+, Mn2+, Ni2+, Co2+; n = 2 and M = Zn2+, Cd2+, Pd2+; n = 0) were synthesized in 1:2 metal ligand ratio. All the metal complexes were characterized by 1H NMR, FTIR, UV-vis, ESI-mass spectrometry, molar conductivity, magnetic and thermal measurements. 1H NMR and IR results showed that the coordination occurs via N and S forming four-membered cyclic ring. Mass spectrum showed the formation of 1:2 metals to ligand stoichiometry. The antibacterial activity of synthesized compounds was evaluated by agar well diffusion method. All the synthesized compounds were evaluated for their DNA nicking activity and found most of metal complexes exhibited good DNA photocleavage activities.