N,O-Bis(trimethylsilyl)acetamide/N-hydroxysuccinimide ester (BSA/NHS) as coupling agents for dipeptide synthesis

A method using N,O-bis(trimethylsilyl)acetamide/N-hydroxysuccinimide ester (BSA/NHS) as coupling agents for dipeptide synthesis is descried. The coupling reaction between N-hydroxysuccinimide (NHS) esters and amines could be performed under mild conditions with N,O-bis(trimethylsilyl)acetamide (BSA) as coupling reagent and no additional acid/base is required. All byproducts and excessive reactants are water soluble or hydrolysable and easy to eliminate through water-washing at the purification stage. Moreover, all the reactants are inexpensive and widely used in conventional drug production.