Small Molecule Approaches Toward Therapeutics for Alzheimer's Disease and Colon Cancer

Abstract

The research described in this dissertation is focused on the knowledge-based, often in silico assisted design, targeted synthesis, and biological evaluation of small molecules of interest for two translational medicinal chemistry projects. The first project (Part 1) is aimed at the identification of blood brain barrier (BBB) penetrable dual specificity tyrosine phosphorylation regulated kinase-1A (DYRK1A) inhibitors as a potential disease modifying approach to mitigate cognitive deficits associated with Alzheimer's neurodegeneration. Two major series with potent activity against DYRK1A were identified in addition to a number of other chemotype sub-series that also exhibit somewhat promising activity. Extensive profiling of active analogs revealed interesting biological activity and selectivity, which led to the identification of two analogs for in vivo studies and revealed new opportunities for further investigation into other kinase targets implicated in neurodegeneration and polypharmacological approaches. The second project (Part 2) is focused on the development of compounds that inhibit PGE₂ production, while not affecting cyclooxygenase (COX) activity, as a novel approach to treat cancer. Compounds were designed with the intention of inhibiting microsomal prostaglandin E₂ synthase-1 (mPGES-1); however, biological evaluation revealed phenotypically active compounds in a cell based assay with an unknown mechanism of action. Further profiling revealed promising anticancer activity in xenograft mouse models. In addition, PGE₂ has been implicated in an immune evasion mechanism of F. tularensis, a strain of bacteria that remains an exploitable threat in biowarfare, thus a small number of analogs were evaluated in a cell model of F. tularensis infection stimulated PGE₂ production.