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Structure Determination of Derivatized Disaccharides by Tandem Mass Spectrometry and Molecular Modeling Louisiana State University LSU Digital Commons LSU Historical Dissertations and Theses Graduate School 2000 Structure Determination of Derivatized Disaccharides by Tandem Mass Spectrometry and Molecular Modeling. Sanford Louis Mendonca Louisiana State University and Agricultural & Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_disstheses Recommended Citation Mendonca, Sanford Louis, "Structure Determination of Derivatized Disaccharides by Tandem Mass Spectrometry and Molecular Modeling." (2000). LSU Historical Dissertations and Theses. 7378. https://digitalcommons.lsu.edu/gradschool_disstheses/7378 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Historical Dissertations and Theses by an authorized administrator of LSU Digital Commons. For more information, please contact [email protected]. INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy subm itted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps. Photographs included in the original manuscript have been reproduced xerographically in this copy. Higher quality 6” x 9” black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. Bell & Howell Information and Learning 300 North Zeeb Road, Ann Arbor, Ml 48106-1346 USA 800-521-0600 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. STRUCTURE DETERMINATION OF DERIVATIZED DISACCHARIDES BY TANDEM MASS SPECTROMETRY AND MOLECULAR MODELING A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfilment of the requirements for the degree of Doctor of Philosophy in The Department of Chemistry by Sanford Mendonca B.S. University of Bombay, 1988 M.S., University of Houston, 1995 December 2000 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number: 9998697 Copyright 2000 by Mendonca, Sanford Louis All rights reserved. ___ ® UMI UMI Microform 9998697 Copyright 2001 by Bell & Howell Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. Bell & Howell Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, Ml 48106-1346 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Copyright © 2000 Sanford Mendonca All rights reserved ii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Dedicated to Monisha, Ninoshka, Nadia, Natalia and Vinton iii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Acknowledgements I would like to express my sincerest and deepest gratitude to my research advisor Dr. Roger Laine for his guidance, support and constant encouragement that enabled me to accomplish my research. I would also like to thank him for taking the time to edit this dissertation. Dr. Laine is the best advisor anyone could ask for. I feel extremely fortunate and highly privileged to have had the opportunity to work with not only a very knowledgeable but also an extremely patient and understanding person. Words cannot express the gratitude within me for the wonderful years I spent associating with him and very fondly cherish it. I would also like to thank Dr. Laine’s family for the support given to me during my graduate career. I would like to express my sincere thanks to Dr. Alfred French who was introduced to me by Dr. Laine for spending countless hours with the modeling work described in this dissertation. I am very grateful to him for being so patient, obliging, for being there when ever I needed to meet him and for sharing with me his vast resources of knowledge. Sincere thanks to Dr. Richard Cole from the University of New Orleans for helping with the mass spectrometry work that was carried out in his laboratory. Sincere thanks to Dr. Patrick Limbach for allowing me unlimited usage of his mass spectrometry instruments and for various suggestions given to me for my research work. Thanks to the committee members for participating in my defense. A special thanks to my wife Monisha for holding the fort at home while I spent my time in the laboratory. I am extremely blessed to have such a wonderful, caring and loving wife. We have been through numerous ups and downs in our six wonderful years of marriage. I am glad I got the opportunity of sharing my life with her. iv Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. wife. We have been through numerous ups and downs in our six wonderful years of marriage. I am glad I got the opportunity of sharing my life with her. My three children Ninoshka, Nadia, and Natalia who put up with all the difficult times we had. They are a great blessing in my life and would like to thank God for three little angels. I would also like to thank God for helping me throughout my graduate career and enabling me to reach the greatest moment in my life. Last but not the least my family, my parents who have waited for this day to come. My brother Vinton for helping me out financially. I could not have asked for a better brother. V Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Table of Contents Acknowledgements .............................................................................................. iv List of Tables .........................................................................................................viii List of Figures ........................................................................................................ ix List of Schemes..................................................................................................... xiv Abstract................................................................................................................. xv Chapter 1. Introduction .................................................................................. 1 Carbohydrates ...............................................................................1 Mass Spectrometry ....................................................................... 9 Mass Spectrometry of Carbohydrates ........................................21 Molecular Modeling of Carbohydrates ..................................... 29 Scope of Work..............................................................................33 References .................................................................................... 35 Chapter 2. Synthesis of Sterically Crowded Derivatives of Anomeric Pairs of Glucose-Glucose Disaccharides ................................42 Introduction .................................................................................... 42 Experimental ................................................................................ 45 References ...................................................................................... 59 Chapter 3. Collision Induced Discrimination of the Glucose l-»4 Disaccharide Anomeric Pair with Incremented Alkyl Substitution ...................................................................... 61 Introduction .................................................................................. 61 Experimental ............................................................................... 69 Results and Discussion ................................................................ 71 Conclusions ....................................................................................125 References ......................................................................................125 Chapter 4. Conformational Analysis of Permethylated Disaccharides Using M M 3 ....................................................................................133 Introduction ....................................................................................133 Methods ..........................................................................................138 Results and Discussion ..................................................................140 Conclusions ....................................................................................181 References ......................................................................................198
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