Efficient synthesis and characterization of imidazo [1,2-a] pyridine-8-carboxamide derivatives: A promising scaffold for drug development

Abstract

Imidazo[1,2‐ a]pyridine, a pivotal fused heterocycle with widespread applications in medicinal chemistry, serves as a foundational scaffold for numerous pharmaceutical compounds. This present approach introduces a highly efficient multi‐step synthetic methodology for imidazo[1,2‐ a]pyridine‐8‐carboxamide derivatives through a condensation reaction between 2‐aminonicotinic acid and chloroacetaldehyde in an environmentally friendly ethanol solvent followed by acid‐amine coupling reaction with a substituted amine. This coupling reaction employs an HATU catalyst and DIPEA strong base and affords excellent yields (93%–97%). A total of ten derivatives have been developed and elucidated by spectral methods, including FT‐IR, ¹ H NMR, and mass spectrometry. In summary, this synthetic strategy possesses favorable attributes for the synthesis of imidazo[1,2‐ a]pyridine‐8‐carboxamide derivatives, such as good purity, readily available starting substrates, wide substrate applicability with simple scale‐up and convenient workup procedure. These characteristics render it a promising method for advanced refinement and prospective utilization in synthesizing crucial therapeutic agents.