NMI/MsCl-Mediated Amide Bond Formation of Aminopyrazines and Aryl/Heteroaryl Carboxylic Acids: Synthesis of Biologically Relevant Pyrazine Carboxamides.

Electron deficient pyrazine amines have been efficiently coupled with a wide range of aryl/hetero aryl acids to yield the corresponding amide intermediates which are known to have a wide range of medicinal relevance. The use of methane sulfonyl chloride and N-methylimidazole to activate the acid was found to be instrumental in driving these reactions to completion and moderate to excellent yields of the coupled products were obtained. All the other coupling agents were found to be inefficient with these electron deficient amines.