Emtricitabine is a potent antiviral drug used in the treatment of HIV and hepatitis B infections. However, during the manufacturing process of emtricitabine, several impurities or by-products may be formed. These impurities can be harmful and may affect the safety and efficacy of the final product. Therefore, it is important to monitor and control the levels of impurities to ensure the quality and safety of emtricitabine.