A Versatile Annulation Route to Primary-Amino-Substituted Naphthyridine Esters

Abstract

A straightforward four-step synthesis of primary-amino-substituted naphthyridine esters from commercially available cyano­pyridines was described. The route makes use of a condensation reaction between pyridinyl acetates with N,N-dimethylformamide dimethylacetal (DMF-DMA) to form ortho-cyano vinylogous carbamates. These intermediates can undergo facile cyclization with ammonium acetate in acetic acid to generate the corresponding naphthyridine esters in good synthetic yields. The synthesis of ­primary-amino-substituted 7-azaquinoxaline was also described.

Key words

naphthyridine - annulation - vinylogous carbamates - heterocycles - scaffold

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