Synthesis, characterisation, crystal structure and biological activity of metal(II) complexes with theophylline

Abstract

Three metal complexes with empirical formulae [Mn(theop)2(H2O)4] (1), [Co(theop)2(H2O)4] (2), [Ni(theop)2(H2O)4] (3), (where: theop = theophylline) were synthesized and characterized by elemental analysis, FTIR- spectroscopy and thermal decomposition techniques. Their crystal structures were determined by single crystal Xray diffraction analysis. Complexes are isomorphous and crystallise in the monocyclic space group P21/c. Their thermal behavior was studied by TGA methods under non-isothermal condition in air. Upon heating all compounds decompose progressively to metal oxides, which are the final products of pyrolysis. Furthermore, antimicrobial and antioxidant activity of the complexes was examined. Keywords: Metal complexes, Thermal investigation, IR spectra, Alkaloids, Theophylline, Antioxidant activity, Biological activity