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Reactive oxygen species (ROS) are a heterogeneous group of highly reactive ions and molecules derived from molecular oxygen (O2), which can cause DNA damage and lead to skin cancer. High levels of ROS can promote cancer development, cancer cell survival, and resistance to chemotherapeutics. NADPH oxidase (NOX) is a significant producer of ROS in the cell. NOX1 generates two superoxide molecules by reducing NADPH. This only occurs when the membrane-bound NOX cytochrome p450 alpha chain (CYBA) binds to the organizer subunit NOXO1 from the cytosolic portions of the holoenzyme on the cell surface. We propose that stopping NOX1 complex subunits from coming together at this CYBA-NOXO1 junction is a potential way to prevent ROS production in human skin cells when exposed to ultraviolet rays.This dissertation investigates potential small-molecule inhibitors of the crucial NOX1 holoenzyme to solve these issues. We designed and synthesized NOX1 specific Inhibitor 1 using a diapocyin backbone structure. Computational docking studies were used to optimize inhibitor design and evaluate the NOXO1 protein subunit specificity. Due to increased binding interaction with NOXO1 protein and to improve solubility of solution preparation for further physical binding studies, we modified Inhibitor 1 and synthesized Inhibitor 2 by adding the NHS-ester Biotin polyethylene glycol chain to the piperidine ring. Both inhibitors were found to be non-toxic in human keratinocyte cells. The Inhibitor 2 reduced the cyclobutene pyrimidine dimer (CPD) DNA mutation in a human skin explant model. Finally, the isothermal calorimetric (ITC) binding assay and MALDI-TOF mass spectrometry were used for physical binding studies to evaluate the critical molecular interaction, leading to the decreased binding affinity of Inhibitor 1, Inhibitor 2, resulting in additional modifications seen in Inhibitor 3 and Inhibitor 4. The results demonstrate that Inhibitor 2 and Inhibitor 3 reduced the binding affinity between NOXO1 protein and CYBA membrane peptide because of a higher binding interaction of the inhibitors with NOXO1 protein, due to the interaction of the polyethylene glycol chain.In the second section of the project, we computationally design and synthesize NOX1-specific inhibitors using the sequence of CYBA peptides as a modeling tool. Through docking studies, we demonstrated inhibitor interference with NOX1 complexes. Several molecules were designed computationally, and three candidate compounds were tested in vitro and demonstrated a reduction of UVR damage in keratinocyte cells. Biophysical studies, like ITC, were performed to identify interactions. Through these studies, an understanding of protein-protein interactions was gained that are essential for discovering and validating inhibitor candidates, along with information for future inhibitor design. To determine the optimum strategy to utilize the biological features of the small molecule NM-166, a structure-activity relationship analysis was performed.