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Investigating the Interactions of Metal Complexes with Heparan Mimetics Wyatt Ohnsonj Virginia Commonwealth University Virginia Commonwealth University VCU Scholars Compass Theses and Dissertations Graduate School 2018 Metalloglycomics: Investigating the Interactions of Metal Complexes with Heparan Mimetics Wyatt ohnsonJ Virginia Commonwealth University Follow this and additional works at: https://scholarscompass.vcu.edu/etd Part of the Chemistry Commons © The Author Downloaded from https://scholarscompass.vcu.edu/etd/5672 This Dissertation is brought to you for free and open access by the Graduate School at VCU Scholars Compass. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of VCU Scholars Compass. For more information, please contact [email protected]. Metalloglycomics: Investigating the Interactions of Metal Complexes with Heparan Mimetics A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Chemical Biology at Virginia Commonwealth University By Wyatt E. Johnson B.S. 2011 Pensacola Christian College M.S. 2013 Pensacola Christian College Director: Nicholas P. Farrell, Professor, Department of Chemistry, School of Humanities and Sciences, Virginia Commonwealth University Virginia Commonwealth University Richmond, VA December, 2018 College of Humanities and Sciences Virginia Commonwealth University This is to certify that the dissertation prepared by Wyatt E. Johnson entitled “Metalloglycomics: Investigating the Interactions of Metal Complexes with Heparan Mimetics” has been approved by his committee as satisfactory completion of the dissertation requirements for the degree of Doctor of Philosophy in Chemical Biology. Nicholas P. Farrell, Ph.D., Director of Dissertation, Chemistry Department, College of Humanities and Sciences Maryanne M. Collinson, Ph.D., Committee Chair, Chemistry Department, College of Humanities and Sciences Umesh R. Desai, Ph.D., School of Pharmacy, Department of Medicinal Chemistry Soma N. Dhakal, Ph.D., Chemistry Department, College of Humanities and Sciences Matthew C.T. Hartman, Ph.D., Chemistry Department, College of Humanities and Sciences M. Sammy El-Shall, Ph.D., Chair, Chemistry Department, College of Humanities and Sciences Montserrat Fuentes, Ph.D., Dean, College of Humanities and Sciences F. Douglas Boudinot, Ph.D., Dean, School of Graduate Studies Date © Wyatt E. Johnson 2018 All Rights Reserved Metalloglycomics: Investigating the Interactions of Metal Complexes with Heparan Mimetics A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Chemical Biology at Virginia Commonwealth University By Wyatt E. Johnson B.S. 2011 Pensacola Christian College M.S. 2013 Pensacola Christian College Director: Nicholas P. Farrell, Professor, Department of Chemistry, School of Humanities and Sciences, Virginia Commonwealth University Virginia Commonwealth University Richmond, VA December, 2018 Acknowledgments I wish to thank several people for their contributions to this work. First, I would like to thank my advisor, Dr. Farrell, for his direction and support of this project and giving me the opportunity to work in his research group, he has pushed me to be the best chemist I could be. This project allowed me to learn new techniques and study the exciting field of metalloglycomics through bioinorganic chemistry in a multi-disciplinary fashion. I would like to thank Dr. Qu for all of her help and guidance particularly through the use of NMR. I would also like to thank Dr. Turner for being an invaluable resource in the instrumentation lab. I am grateful to all of the members of the Farrell group, especially Erica for always being there when I had questions and Jamie for allowing me to discuss countless hours of chemistry with him. I am also grateful to the other members of the Farrell lab group: Daniel, Samantha, Sarah, Eric, Samantha, Tom, and David, and the visiting students who have always been available to help me. I would also like to thank my committee members for all of their helpful suggestions and for keeping me on track with my projects. Finally, I wish to thank my wife, Brittany, without her support both financially and emotionally I would not have been able to finish this degree, she always pushed me to be better; and I am eternally grateful that she was willing endure throughout my education process. i Table of Contents List of Tables…………………………………………………………………………………….iii. List of Figures……………………………………………………………………………….........v. List of Abbreviations……………….……………………………………………………….........ix. Abstract…………………………………………………………………..…………………........xi. Chapter 1. Introduction……………………………………………………………………………1. Chapter 2. Non-Covalent Polynuclear Platinum Complexes as Metalloshielding Agents for Heparan Sulfate…………………………..……………………………………………………...50. Chapter 3. Comparison of Metal–Ammine Compounds Binding to DNA and Heparin. Glycans as Ligands in Bioinorganic Chemistry……………………………………………………………...99. Chapter 4. Cobalt Complexes Interactions with the HS Mimetic Fondaparinux and Their Dual Therapeutic Potential. ……………………………………………………………….................136. Chapter 5. Interactions of Non-covalent Metal Complexes with Fondaparinux……………......159. Chapter 6. Metalloglycomics: Probing the Metalloshielding Interactions of Simple Metal Complexes with Fondaparinux…………….…………..………………………………............171. Chapter 7. Synthesis and Characterization of Werner’s Complex……………………….…......181. Chapter 8. Conclusions…………………………………………..……….………………….....185. Appendix……………………………………………………….…………………………........189. Vita……………………………………………………………….………………………….....196. ii List of Tables Table 2.1. 1H NMR chemical shift changes…………………………………………………….58. Table 2.2. Interaction energies of isolated phosphate and sulfate anions and heparin fragments with Pt coordination spheres in the PPC library………………………………………………...71. Table 2.3. FPX–PPC dissociation constants as measured by methylene blue (MB), ethidium bromide (EtBr) reporter assays and isothermal titration calorimetry (ITC)…………………….79. Table 2.4. ITC analysis showing the obtained binding parameters……………………………..85. Table 2.5. Cytotoxicity of noncovalent PPCs in HCT116 cells………………………………...89. Table 3.1. IC50 and Kd values of TriplatinNC and Metal-ammine compounds in competitive inhibition assays using MB or TAMRA-R9………………………………………………….....109. Table 3.2. A comparison of dissociation constants and Gibbs free energy by ITC……………...117. Table 3.3. Fluorescence Polarization Assays Showing That Heparin Is a Competitor for Metal– Ammine Compound Binding to DNA………………………………………………………….121. Table 3.4. TriplatinNC bound to fluorescently labeled DNA competes with “cold” unlabeled DNA……………………………………………………………………………………………121. Table 3.5. EtBr Competition Assay for Comparison of Metal–Ammine Binding to DNA and Heparin…………………………………………………………………………………………123. Table 4.1. 1H and 59Co chemical shift changes (Δδ = δ(monomer : Co) – δ(monomer/Co)) after incubation of Co complexes with D-glucosamine-6-O-sulfate....................................................142. Table 4.2. Species detected using 59Co NMR..............................................................................144. Table 4.3. Species detected on the ESI-MS spectra.....................................................................146. Table 4.4. ITC analysis showing the obtained binding parameters..............................................148. Table 4.5 IC50 and Kd values of cobalt complexes in competitive inhibition assays using MB....150. Table 5.1. Species detected on the ESI-MS spectra.....................................................................162. Table 5.2. ITC analysis showing the obtained binding parameters..............................................164. Table 5.3. 1H chemical shift changes (Δδ = δ(monomer : Co) – δ(monomer)) after incubation of metal complexes with D-glucosamine-6-O-sulfate.....................................................................166. iii Table 5.4. IC50 and Kd(app) Values of metal compounds in the competitive inhibition assay using MB as a reporter..........................................................................................................................168. Table 6.1. IC50 values of metal compounds in the competitive inhibition assay using MB as a reporter…………………………………………………………………………………………175. Table 6.2. Species detected on the ESI-MS spectra…………………………………………….175. iv List of Figures Figure 1.1. Structures of FDA approved platinum-based anticancer drugs………………………2. Figure 1.2. Pathways for GG intrastrand crosslinking of DNA by cisplatin.…………….………2. Figure 1.3. Structure of sulfur containing nucleophiles………………………...………………...4. Figure 1.4. Resistance pathways for cisplatin and its analogs after DNA binding………...……..4. Figure 1.5. Unique cross-links formed by transplatin derivatives……………………...………...6. Figure 1.6. Structures of transplatin and BBR3464………………………………………...…….6. Figure 1.7. Structures from molecular modeling of the major DNA adducts of BBR3464…...…8. Figure 1.8. Structures of platinum complexes………………………………………………...….8. Figure 1.9. Structure of NAMI-A and M40403………………………………………...……….10. Figure 1.10. Structure of CTC and Cohex…………………………………………………...….10. Figure 1.11. Heparan sulfate (HS) can play multiple roles during viral infection………………12. Figure 1.12. Chemical structures of cobalt(III) coordination complexes used in early biological studies…………………………………………………………………………………………...12. Figure 1.13. Comparison of cytotoxicity of Cohex against BHK cells with cisplatin………….13. Figure 1.14. The proposed mechanism of action of Co(III)-acacen complexes………………...13.
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