Acetamidine-d3 hydrochloride is primarily used in research and development, particularly in the fields of biochemistry and pharmacology. It serves as a deuterated analog of acetamidine, making it valuable in studies involving isotopic labeling. This compound is often employed in mass spectrometry and NMR spectroscopy to track and analyze metabolic pathways and drug mechanisms. Its deuterium atoms enhance the precision of these analytical techniques, allowing researchers to gain deeper insights into molecular interactions and transformations. Additionally, it is utilized in the synthesis of deuterated pharmaceuticals, aiding in the development of drugs with improved stability and efficacy.