Cytotoxicity and antiviral activity of transition-metal salicylato complexes and crystal structure of Bis(diisopropylsalicylato)(1,10-phenanthroline)copper(II)

Abstract

Complexes of Cu^II, Fe^III, Co^II, Ni^II, Ti^IV and Zn^II with 3,5-disubstituted salicylates, and ternary complexes of Cu^II containing substituted phenanthrolines have been prepared and characterised. The crystal structure of bis(diisopropylsalicylato)(1,10-phenanthroline)copper(II), [Cu(phen)(Hdips)₂], has been determined; Cu^II is in a tetragonal co-ordination environment with in-plane bonds to 2 nitrogens from phen[Cu–N 2.014(4)Å] and 2 oxygens from the carboxylates of Hdips [Cu–O 1.951(3)Å], with weaker off-axial bonds to carboxylate oxygens [Cu–O 2.557(3)Å]. The hydroxyl oxygen of Hdips is not co-ordinated. These complexes have been tested for antiviral and cytotoxic activity. Most are potently cytotoxic, especially [Cu(dmphen)(Hdips)₂], where dmphen is 2,9-dimethylphenanthroline.