Photoactive Metal Nitrosyl and Carbonyl Complexes Derived from Designed Auxiliary Ligands: An Emerging Class of Photochemotherapeutics

The occurrence of carbon monoxide (CO) and nitric oxide (NO) in human physiology and the potential of metal nitrosyl and carbonyl complexes as pharmaceuticals have added new paradigms in modern biology and medicine. In addition to one or more NO or CO as ligands, these metal complexes contain designed organic frames as auxiliary ligand(s). These auxiliary ligands have been carefully tailored so as to promote release of NO or CO from the resulting nitrosyls and carbonyls upon exposure to light of selected wavelengths and with desired efficiencies. Once isolated, the NO and CO releasing molecules (NORMs and CORMs, respectively) have been subjected to a wide range of in vitro and in vivo biological experiments to evaluate the utility of the photoactive NORMS and CORMs as photochemotherapeutics. This chapter focuses on the results from these pursuits by various groups during the past few years.