Phosphate ester linkages are omnipresent in nature and are found in many biologically important molecules such as DNA, RNA and ATP. Many enzymes that hydrolyze phosphate esters are activated by metal ions. Since the structure of biological enzymes can be quite complicated, it is often useful to work with simpler artificial metalloenzymes to help elucidate the mechanisms by which phosphate ester hydrolysis is activated by metals. / In principle, simple dinuclear metal complexes could hydrolyze phosphate esters by double Lewis acid activation or by a combination of single Lewis acid activation and metal-hydroxide activation. These two mechanisms are kinetically indistinguishable. In this study, two different phosphate substrates are used to distinguish these mechanisms. / Lanthanide (iii) salts have proven extraordinarily effective in accelerating the rate of phosphate ester hydrolysis by several orders of magnitude. Consequently, there has been much effort in recent years to develop a ligand that would bind lanthanides so as to further improve their ability to hydrolyze phosphates. These efforts have met with limited success. Reported here is a dinuclear lanthanide (iii) complex which hydrolyzes BNPP (bis p-nitrophenyl phosphate) with unprecedented reactivity at pH 7.0 and 25°C. / A mononuclear copper (ii) 6,6'-diamino-2,2 '-bipyridyl complex is synthesized which gives one of the fastest rate accelerations reported for hydrolyzing 2',3 '-cAMP. A hydrogen bonding mechanism is proposed for the acceleration of the rate of hydrolysis of the cyclic phosphate.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.35551 |
| Date | January 1999 |
| Creators | Williams, Daniel M. |
| Contributors | Chin, Jik (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Chemistry.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001737861, proquestno: NQ55393, Theses scanned by UMI/ProQuest. |
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