Ethyl 5-trichloromethyl-1,2,4-oxadiazole-3-carboxylate as a versatile building block in medicinal chemistry

A straightforward route for preparing derivatives of ethyl 5-trichloromethyl-1,2,4-oxadiazole-3-carboxylate, in which the 5-trichloromethyl and/or the ester functionalities are displaced by various nucleophiles, has been designed. Mild reaction conditions were chosen to enable the formation of products, which constitute a new series of bifunctional 3,5-disubstituted 1,2,4-oxadiazole building blocks capable of being integrated into biologically relevant molecules.