Facile three-component synthesis and insecticidal evaluation of hexahydroimidazo[1,2-a]pyridine derivatives

A series of new hexahydroimidazo1,2-a]pyridine derivatives were synthesized via convenient and practical three-component reactions. Preliminary bioassays showed that majority of the target compounds exhibited moderate to excellent insecticidal activity against cowpea aphids (Aphis craccivora). Among them, compound 9l demonstrated significant activity with LC₅₀ value of 0.00918 mmol/L which was about 3.8-fold higher than that of imidacloprid (IMI). Furthermore, the study of stereostructure-activity relationship of four isomers of 9k indicated that configuration played a key role in insecticidal activity of these compounds.