The purpose of this research is to determine the mechanism of radical quenching of novel antioxidants. In chemistry, a free radical is defined as a compound with a single unpaired valence electron. These species are usually unstable and can damage molecules such as DNA by uncontrolled oxidation reactions. When a radical reacts with a molecule and single electron transfer occurs, the compound which lost the electron has been "oxidized." As a result, a new radical is produced, and the process is repeated in a chain reaction. This process is potentially dangerous to many living organisms including human tissues and is related to aging. Antioxidants, as the expression implies, exist to counter this phenomenon by 'quenching' the radical thus inhibiting further oxidation reactions. Vitamin C and E are common antioxidants that most individuals are familiar with in everyday life.   This research investigated two reaction mechanisms: single electron transfer (SET) and hydrogen atom transfer (HAT). By reacting the antioxidants with the stable radical 2,2-diphenyl-1-picrylhydrazyl, or DPPH, the rate of radical reaction can be determined under controlled conditions that favor either the SET or HAT mechanism. While both are mechanisms are possible in the DPPH quenching reaction, one will dominate over the other in certain conditions. These conditions include pH, solvent, and antioxidant strength. Current data show that methanol and ethanol solvents favor single electron transfer due to the alcohol's tendency for hydrogen bonding. Our research studied the rate of DPPH quenching for five novel antioxidants: 3-hydroxythiophene-2-carboxylic acid (HTC), 2H,4H,5H,6H,7H,7aH-thieno[3,2-C] pyridin-2-one (TPO), Methyl 3-hydroxy-1H-pyrrole-2-carboxylate (MHPC), 2,5-dihydro-4-hydroxy-2-oxo-1H-pyrrole-3-carboxylic acid methyl ester (PCME), and 5-Trityl-5,6,7,7a-tetrahydrothieno-[3,2-c] pyridin-2(4H)-one (TTTP).