| itric oxide is an important signaling molecule in biological processes such as blood pressure regulation and neurotransmission. The heme enzyme soluble guanylate cyclase is the best known receptor for nitric oxide. Even though the mechanism on the activation of soluble guanylate cyclase by nitric oxide is well known, the mechanism for down-regulation of nitric oxide from the heme center remains unknown.;In chapter two, two nitrosodicyanomethanide complexes, Fe(III)(TTP)(ONC(CN);As an extension of the iron nitric oxide complex research, the first related ruthenium porphyrin thionitrosyl complexes has been prepared and characterized. The Ru(TTP)(NS)Cl was prepared from the reaction of Ru(TTP)(CO)(MeOH) with trithiazyl trichloride. An unusual thionitrosyl/nitrite to nitrosyl/thiazate transformation results when Ru(TTP)(NS)Cl is treated with silver nitrite. The single crystal structure of Ru(TTP)(NO)(NSO) has been characterized. The measurements of physical properties and an independent synthesis from the reaction Ru(TTP)(NO)(Cl) with thiazate anion were carried out. All of the physical properties between isoelectronic Ru(TTP)(NO)Cl and Ru(TTP)(NS)Cl complexes indicate that the nitrosyl group is a better ;The last two chapters in this dissertation describe the coordination chemistry of a tetradentate ligand (2S, 2S;The first section of this dissertation concerns a series of model complexes designed to help us understand which factors regulate the metal-nitric oxide bond strengths and dissociation rates in iron(II) porphyrin nitrosyl complexes. A series of new nitrosyl complexes based on tetraphenylporphyrin are synthesized with substituents either on the phenyl rings or on the... |
