Publication Date


Document Type


Committee Members

David Dolson (Committee Member), Eric Fossum (Committee Member), Paul Seybold (Advisor)

Degree Name

Master of Science (MS)


Pyrimidines and related heterocycles are an important class of compounds with a wide variety of applications. As a result, there is great interest in the chemical properties of these compounds, specifically their pKa's. Despite the importance of these compounds their reported pKa's are often only approximations or are completely absent from literature. Experimentally measuring pKa's can be challenging, especially if the pKa is below zero. Alternatively, pKa's can be estimated computationally using a Quantitative Structure-Activity Relationship (QSAR). However, most of the compounds included in this study exist as two or more forms that arise from tautomerism. Tautomerism complicates the estimation of pKa's because proton transfers result in a rearrangement of electron density that alters chemical behavior. As a result, pKa's are unique to each tautomeric species. This research identifies the most stable tautomer associated with each of the compounds included in this study. From here QSAR models have been constructed using a variety of molecular descriptors. The resulting QSAR models are then used to estimate the pKa's of compounds for which there are currently no literature values.

Page Count


Department or Program

Department of Chemistry

Year Degree Awarded



Included in

Chemistry Commons