2,4-Dithiouridine is a modified nucleoside where the oxygen atoms at the 2- and 4-positions of the uracil base are replaced by sulfur atoms. This structural modification significantly alters its chemical and biological properties compared to the canonical nucleoside uridine. Its primary application is in biochemical and biophysical research. The sulfur substitutions make it a useful probe for studying RNA structure, dynamics, and protein-RNA interactions, particularly through techniques like Raman spectroscopy where it serves as a sensitive vibrational reporter. It is also investigated for its potential in the development of antiviral and anticancer agents, as modified nucleosides can act as metabolic inhibitors or be incorporated into oligonucleotides to alter their function and stability. As a thionated nucleoside derivative, it serves as a specialized building block (synthetic intermediate) for the preparation of more complex oligonucleotide analogs and prodrugs. Its handling requires standard precautions for laboratory chemicals.