Coupling reagents are chemical substances used to facilitate the formation of bonds between two molecules, often in the context of organic synthesis. They are particularly important in the creation of peptides, nucleotides, and other complex organic compounds. By activating one of the reactants, coupling reagents help to promote the desired reaction, making it more efficient and selective. Common examples of coupling reagents include DIC (N,N'-diisopropylcarbodiimide) and EDC (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide). These reagents are widely used in laboratory settings to link amino acids or other functional groups, enabling the development of pharmaceuticals and biochemicals. Their role is crucial in advancing chemical research and applications.