CI 976 is primarily used in the field of biochemistry and pharmacology as a potent inhibitor of acyl-CoA:cholesterol acyltransferase (ACAT). This enzyme plays a crucial role in cholesterol esterification, making CI 976 a valuable tool in research focused on understanding lipid metabolism and its implications in diseases such as atherosclerosis. By inhibiting ACAT, CI 976 helps reduce the accumulation of cholesterol esters in cells, which is beneficial in studies aimed at developing therapeutic strategies for managing hypercholesterolemia and related cardiovascular conditions. Additionally, it is utilized in laboratory settings to investigate the mechanisms of cholesterol absorption and storage, providing insights that could lead to the development of new drugs targeting lipid-related disorders.