Structural studies of organic crystals of pharmaceutical relevance. Correlation of crystal structure analysis with recognised non-bonded structural motifs in the organic solid state
Thesis-Abstract,table of contents.pdf (338.2Kb)Download
Thesis introduction-chapter one.pdf (483.8Kb)Download
Thesis-experimental-chapter 2.pdf (197.5Kb)Download
Chalcones-chapter 3.pdf (1.147Mb)Download
cryptolepines -chapter 4.pdf (1.108Mb)Download
Biguanides-chapter 5.pdf (1.088Mb)Download
xanthines-chapter 6.pdf (1.503Mb)Download
CONCLUSION -chapter 7.pdf (47.30Kb)Download
Thesis-Appendix-A,B and C.pdf (239.4Kb)Download
INFRA_RED-Appendix D.pdf (981.8Kb)Download
PXRD-Appendix E.pdf (1.071Mb)Download
Raman-Appendix F.pdf (776.0Kb)Download
Mass Spec-Appendix G.pdf (302.6Kb)Download
NMR-Appendix H.pdf (2.749Mb)Download
SupervisorScowen, Ian J.
Edwards, Howell G.M.
KeywordSingle crystal structure
; Structural motifs
; Pharmaceutical solids
; Physico-chemical stability
; Crystallization studies
The University of Bradford theses are licenced under a Creative Commons Licence.
InstitutionUniversity of Bradford
DepartmentSchool of Pharmacy
MetadataShow full item record
AbstractPharmaceutical solids tend to exist in different physical forms termed as polymorphs. Issues about pharmaceutical systems are mainly concerned with the active ingredient's physico-chemical stability and bioavailability. The main aim of this study is to investigate the non-bonded interactions in pharmaceutical solids that govern the physical pharmaceutics performance of such materials and through the use of structural techniques and correlation of these results with crystal structural database to establish the presence of physical motifs in selected systems. Structural motifs were identified by the use of single crystal and crystal packing analysis on diverse range of pharma-relevant materials including chalcones, cryptolepines, biguanides and xanthines. These selected systems were validated using functional group and molecular analysis and correlating them to the Cambridge Structural Database. Crystallization studies are done on these selected systems as well as exploiting those using synthetic analogues. A total of 51 crystal structures were investigated including 16 new structure determinations. Addition synthesis of new xanthines to investigate novel intermolecular patterns was also undertaken. The understanding and exploitation of intermolecular interactions involving hydrogen bonds and coordination complexation during packing can be used in the design and synthesis of solid state molecular structures with desired physical and chemical properties.
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