ESR Spectroscopy of Temperature Accessible Lowest Triplet States of Biology Active Electron-Rich 1,10- Phenanthrocyanines of d-Elements (Soft Colloidal Glasses)

Temperature accessible lowest electronic triplet biradical states of new metal 1,10-phenanthrocyani-nes were investigated by ESR spectroscopy. These are coordination compounds of a new structural class of cyanines: nanosize chromophore binuclear cation complexes of d-elements [M z+ L n (µ-PC)] 2 X n (M z+ =Zn 2+ , Cd 2+ , Pd 2+ and Pt 2+ ; L=1,10-phen, py, AcO - ; X=AcO - , Cl - ) with electron-rich 1,10-phenanthrocyanine ligands. They are presented as redox-sensitive polymorphic soft collo-idal glasses capable of acting as inhibitors of tumor cell proliferation, environmentally friendly fun-gicides and DNA complexones related with NADH. The study of them by ESR spectroscopy sho-wed that one of the possible detailed mechanisms of the formation of triplet states in the processes of thermo-directed singlet-triplet S 0 →T low. -transitions consists in thermally activation of rotation around the sesquialteral C—C bond dihydro-1,10-phenanthroline and 1,10-phenanthroline frag-ments in the bridged chromophore system of compounds.