Abstract
Mesoionic pyrido[l,2-a]pyrimidinones are a unique class of heterocyclic compounds.Compounds from this class with a n-propyl group substituted at the 1 position of the mesoionic core were discovered with interesting insecticidal activity in our screen.In this overview,we showcase how a bioisosteric replacement strategy was applied during the discovery and optimization of this class of compounds.Through exploring various substituents at the 1 position,evaluating a variety of mesoionic bicyclic ring scaffolds,and examining substituents on the phenyl group at the 3 position of the mesoionic core as well as substituents on the mesoionic ring skeleton,many compounds were discovered with excellent hopper activity or potent activity against a wide range of Lepidoptera.Ultimately,dicloromezotiaz was identified for commercial development to control a broad spectrum of lepidopteran pests.
NSTL