Timothy L. Macdonald

Timothy L. Macdonald is a faculty member in the Department of Chemistry at the University of Virginia, specializing in Bioorganic and Synthetic Organic Chemistry. His research program focuses on applying organic chemical theory and techniques to investigate biological problems, with particular emphasis on small molecule-protein interactions fundamental to physiology, pharmacology, and toxicology.

Dr. Macdonald's research interests include:

• Elucidation of molecular pharmacology of ligand-receptor interactions
• Identification of molecular processes underlying idiosyncratic drug reactions
• Determination of chemical mechanisms of oxidative transformation by enzymes
• Characterization of molecular mechanisms of neurotoxicity
• Development of new therapeutic agents targeting specific biological pathways

His current research focuses on several key areas including the lysophospholipid signaling system (particularly lysophosphatidic acid and sphingosine-1-phosphate), ligand-receptor interactions forming ternary DNA-drug complexes with topoisomerase enzymes, and molecular mechanisms of idiosyncratic drug reactions such as aplastic anemia associated with felbamate. His work integrates synthetic chemistry with mechanistic studies to advance knowledge in antitumor drug development and design new structural classes of inhibitors.

Dr. Macdonald's publications demonstrate expertise across multiple disciplines including biochemistry, pharmacology, organic chemistry, and microbiology. His research shows particular strength in lipid chemistry, receptor pharmacology, and drug development for cancer, neurodegenerative diseases, and infectious disease applications.

His scientific contributions include work on:

• Calcium channel regulation in cancer and stem cells
• Lysophosphatidic acid synthesis and signaling pathways
• Novel antibiotic development against Clostridium difficile
• LPA receptor antagonists with improved metabolic stability
• Sphingosine kinase inhibition and sphingolipid metabolism
• Mechanisms of neurotoxicity related to Parkinson's and Alzheimer's diseases