Synthesis of novel pyrazine-containing amidoesters via Passerini multicomponent reaction

Here, the synthesis of 2-(cyclohexylamino)-2-oxo-1-arylethyl pyrazine-2-carboxylates is reported using the Passerini reaction between cyclohexyl isocyanide and pyrazine-2-carboxylic acid in the presence of aromatic aldehydes. This procedure allows us to synthesize pyrazine-containing novel amidoesters that may be important structures in medicinal and chemical sciences. All synthesized products are stable structures that yield between 85 and 96% in ethanol as the desired solvent for this reaction. The reaction proceeds under neutral conditions to generate a final Passerine reaction product with no side reactions. The structures of all the new compounds were elucidated on the basis of their spectroscopic data, such as 1 H and 13 C NMR.