Graduation Year
2010
Document Type
Dissertation
Degree
Ph.D.
Degree Granting Department
Chemistry
Major Professor
Mark L. Mclaughlin, Ph.D.
Committee Member
Jon Antilla, Ph.D.
Committee Member
Wayne C. Guida, Ph.D.
Committee Member
John Koomen, Ph.D.
Committee Member
Roman Manetsch, Ph.D.
Keywords
MDM2, p53, α-helix, apoptosis, protein
Abstract
The p53 protein promotes tumor eradication upon activation, making it an attractive target in cancer therapies. A reported 50% of all human cancers display aberrant activation of the MDM2 oncoprotein, which directly promotes tumorgenesis by inactivating the transcriptional activity of wild type p53, and is commonly associated with drug, chemo, and radio therapy resistance. Previously reported crystallographic analysis of the p53/MDM2 complex infers that the p53 protein forms a 2.5 turn amphipathic alpha helix whose hydrophobic face interacts within a deep hydrophobic cleft in the NH2-terminal domain of the globular MDM2. This suggests that the synthesis of small molecular antagonists of p53/MDM2 binding interactions, capable of reactivating wild type p53 function, show a promising therapeutic strategy in pharmaceutical discovery. The use of alpha helix mimics for the disruption of p53/MDM2 binding interactions has been amply documented in the literature; however, these compounds contain hydrophobic scaffolds that limit their usefulness as potential drug candidates. Presented is the design, synthesis, and biological evaluation of novel non-peptidic, drug-like, small molecule inhibitors to target p53/MDM2 binding interactions. The mimetics are designed to bind to the NH2-terminal domain of MDM2 protein leaving p53 unbound and capable of activation. The inhibitor design is based on an alpha helix mimetic scaffold derived from functionalized piperazines, diketopiperazines, and/or pyrimides. The mimetics are designed to have a comparably higher degree of solubility and notably facile synthesis yet still maintain the desired spacial arrangements of hydrophobic side chains in the ith, ith+4, and ith+7 positions of a natural alpha helix. The small molecules are designed to act as antagonists of protein/protein interactions, tumor inhibitors, and potent p53 activators.
Scholar Commons Citation
Topper, Melissa Elizabeth, "Design, Combinatorial Synthesis, and Biological Evaluation of Novel α-Helical Mimetics Based on Functionalized Piperazines as Antagonists of p53/MDM2 Interactions" (2010). USF Tampa Graduate Theses and Dissertations.
https://digitalcommons.usf.edu/etd/3454
