Synthesis, characterisation and thermal behaviour of some thiosulfato-and sulfato copper(II) complexes

The investigation concerning the synthesis, spectrochemical and biological properties as well as thermal stability of some tiosulfato-and sulfato copper(II) complexes of type [Cuphen(S₂O₃)(H₂O)_n]·mH₂O (phen: 1,10-phenanthroline; (1): n=2, m=0; (2): n=2, m=0.5) and respectively [Cuphen(OSO₃)(H₂O)_n] ((3): n=0; (4): n=2) are presented in this paper. The bonding and stereochemistry of the complexes have been characterised by IR and electronic studies. The in vitro qualitative and quantitative assays of the antimicrobial activity of the tested compounds vs. planktonic and adherent Gram negative bacterial strains isolated from different surfaces in the hospital environment demonstrated that all compounds exhibited very good antimicrobial activity vs. Escherichia coli, Klebsiella sp. and Enterobacter sp. with very low M.I.C. values. The thermal analysis has evidenced the thermal intervals of stability and also the thermodynamics effects that accompany them both in synthetic air and argon. The thermal behaviour is complex according to DTG and DSC curves including dehydration as well as thiosulfate and phenanthroline decomposition.