Design, synthesis, and insecticidal activities of novel analogues of neonicotinoids: Replacement of nitromethylene with nitroconjugated system

To replace nitromethylene pharmacophore with a nitroconjugated system, a series of novel neonicotinoid analogues bearing five-membered aromatic heterocycles were designed and synthesized. Bioassays indicated that some of the synthesized compounds exhibited higher insecticidal activities than imidacloprid against cowpea aphids (Aphis craccivora), armyworm (Pseudaletia separate Walker), Nephotettix bipunctatus (Fabricius), and small brown rice planthopper (Laodelphasx striatellus). Exhilaratingly, the activity levels of derivatives 13a and 13j rivaled that of imidacloprid.