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Reactivity and Mechanistic Aspects of NO and HNO Donors

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Reactivity and Mechanistic Aspects of NO and HNO Donors Reactivity and Mechanistic Aspects of NO and HNO Donors Item Type text; Electronic Dissertation Authors Jorolan, Joel Hao Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 10/10/2021 22:52:24 Link to Item http://hdl.handle.net/10150/321545 REACTIVITY AND MECHANISTIC ASPECTS OF NO AND HNO DONORS By Joel Hao Jorolan _________________________________________ A Dissertation Submitted to the Faculty of the DEPARTMENT OF CHEMISTRY AND BIOCHEMISTRY In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY WITH A MAJOR IN CHEMISTRY In the Graduate College THE UNIVERSITY OF ARIZONA 2014 THE UNIVERSITY OF ARIZONA GRADUATE COLLEGE As members of the Dissertation Committee, we certify that we have read the dissertation prepared by Joel Hao Jorolan, titled Reactivity and Mechanistic Aspects of NO and HNO Donors and recommend that it be accepted as fulfilling the dissertation requirement for the Degree of Doctor of Philosophy. ______________________________________________ Date: May 6, 2014 Dr. Katrina Miranda ______________________________________________ Date: May 6, 2014 Dr. Dennis Lichtenberger _______________________________________________ Date: May 6, 2014 Dr. Scott Saavedra _______________________________________________ Date: May 6, 2014 Dr. Elisa Tomat Final approval and acceptance of this dissertation is contingent upon the candidate’s submission of the final copies of the dissertation to the Graduate College. I hereby certify that I have read this dissertation prepared under my direction and recommend that it be accepted as fulfilling the dissertation requirement. ________________________________________________ Date: May 6, 2014 Dissertation Director: Dr. Katrina Miranda 2 STATEMENT BY AUTHOR This dissertation has been submitted in partial fulfillment of the requirements for an advanced degree at the University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library. Brief quotations from this dissertation are allowable without special permission, provided that an accurate acknowledgement of the source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his or her judgment the proposed use of the material is in the interests of scholarship. In all other instances, however, permission must be obtained from the author. SIGNED: Joel Hao Jorolan 3 ACKNOWLEDGMENTS I would like to express my sincere gratitude to my Ph.D. advisor, Dr. Katrina M. Miranda for her constant support and guidance all throughout my graduate career. She has provided me with opportunities to explore, grow and learn as a scientist. Without her help, this dissertation would not have been possible. I would like to thank my Ph.D. committee, Drs. Dennis Lichtenberger, Scott Saavedra, and Elisa Tomat for their valuable time and scientific input. I would also like to express my gratitude to the members of Miranda group for moral support and friendship. I also thank the Department of Chemistry and Biochemistry research support staff who are always willing to help with my research needs. Thank you to my friends for making my stay here in Tucson a very memorable one. I would like to thank my parents for instilling in me the importance of education and inspiring me to aim high. And lastly to my wife, whose support has made this accomplishment possible. 4 DEDICATION For my beautiful wife Honniegyn, my daughter Hanjel, and my parents Jorge and Norma. I love you. 5 TABLE OF CONTENTS LIST OF FIGURES ........................................................................................................ 11 LIST OF SCHEMES ...................................................................................................... 16 LIST OF TABLES .......................................................................................................... 18 LIST OF ABBREVIATIONS ........................................................................................ 19 ABSTRACT ..................................................................................................................... 22 CHAPTER 1 INTRODUCTION .................................................................................. 24 1.1 Nitric Oxide ........................................................................................................... 25 1.1.1 Chemistry of NO ........................................................................................... 26 1.1.2 Donors of NO ................................................................................................ 29 1.1.2.1 Organic nitrate esters ................................................................................ 29 1.1.2.2 S-Nitrosothiols .......................................................................................... 30 1.1.2.3 Secondary amine diazeniumdiolates ......................................................... 31 1.1.2.4 Metal nitrosyl complexes .......................................................................... 33 1.2 Nitroxyl .................................................................................................................. 37 1.2.1 Chemistry of HNO ........................................................................................ 38 1.2.2 Donors of HNO ............................................................................................. 40 1.2.2.1 Angeli’s salt and primary amine diazeniumdiolates ................................. 41 1.2.2.2 N-hydroxysulfonamides ............................................................................ 43 1.2.2.3 Acyl nitroso compounds ........................................................................... 44 1.2.2.4 Acyloxy nitroso compounds ..................................................................... 45 6 1.2.3 Autoxidation of HNO .................................................................................... 46 1.3 Peroxynitrite .......................................................................................................... 47 1.3.1 Physical and chemical properties of ONOO- ................................................. 47 1.3.2 Pathways for formation of ONOO- ................................................................ 49 1.3.1 Chemical and biological reactivity of ONOO- .............................................. 50 1.3.1.1 Direct reactions ......................................................................................... 51 1.3.1.2 Reactions with OH and NO2 ..................................................................... 53 1.3.2 Synthesis of ONOO- ...................................................................................... 54 1.4 Chapter 1 Summary ............................................................................................... 57 CHAPTER 2 COMPARISON OF THE CHEMICAL REACTIVITY OF SYNTHETIC PEROXYNITRITE WITH THAT OF THE PRODUCTS OF NITROXYL OR ITS ANION WITH MOLECULAR OXYGEN ................................................................................................. 58 2.1 Introduction ........................................................................................................... 58 2.2 Materials and Methods .......................................................................................... 63 2.2.1 Chemicals ...................................................................................................... 63 2.2.2 Instrumentation .............................................................................................. 64 2.2.3 Nitrite and nitrate assay ................................................................................. 64 2.2.4 Fluorescent assays ......................................................................................... 65 2.3 Results and Discussion .......................................................................................... 65 2.3.1 Standard synthesis of ONOO- ....................................................................... 65 2.3.2 Synthesis of ONOO- from aerobic decomposition of IPA/NO ..................... 66 7 2.3.3 Nitrite and nitrate ........................................................................................... 68 2.3.4 Product formation during decomposition of IPA/NO ................................... 69 2.3.5 Oxidation of HPA .......................................................................................... 70 2.3.6 Hydroxylation of benzoic acid ...................................................................... 76 2.3.7 Oxidation of DHR and effect of buffer composition ..................................... 78 2.3.8 Effect of pH ................................................................................................... 79 2.4 Chapter 2 Summary ............................................................................................... 85 CHAPTER 3 INVESTIGATIONS ON THE MECHANISM OF THE CATALYTIC CONVERSION OF NITRITE TO NITRIC OXIDE BY A RUTHENIUM NITROSYL COMPLEX .............................................. 87 3.1 Introduction ..........................................................................................................
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