HATU is a highly efficient and widely used coupling reagent in peptide synthesis and organic chemistry. It facilitates the formation of amide bonds by activating carboxylic acids for nucleophilic attack by amines, often leading to high yields and minimal racemization. HATU is a uronium-type reagent that incorporates 7-azabenzotriazole as the leaving group, which enhances its reactivity compared to other coupling agents like HBTU or DCC. Its structure includes a uronium core with tetramethyl substitution and a hexafluorophosphate (PF₆⁻) counterion, contributing to its stability and solubility in polar organic solvents such as DMF and DMSO. Due to its high efficiency, HATU is particularly favored in solid-phase peptide synthesis (SPPS) and other applications requiring reliable amide bond formation.