Alireza Hasaninejad

1,2,4,5,9,10,12,13-octaaza[16]annulene-3,11-dithiol is Hydrazone Schiff Base (Figure 1). Hydrazones are special class of compounds in the Schiff bases family. Hydrazone Schiff bases of acyl, aroyl, and heteroaroyl compounds have an addition donor sites like C=O. The additional donor sites make them more flexible and versatile. This versatility has made hydrazones good polydentate chelating agents that can form a variety of complexes with various transition and inner transition metals and have attracted the attention of many researchers. The importance of these complexes also is due to the role they play as models for protein metal binding sites in biological systems, electrocatalysts infuel cells, MRI contrast agents, luminescent sensors.