Abstract
A chlorothiazole-based hexamethylene divalent neonicotinoid and trivalent 1,3,5-tris[1-(6-chloronicotinyl)-2-nitroiminoimidazolidin-3-ylmethyl]benzene were synthesized, and tested for the insecticidal activity using American cockroaches by injection without (alone) and with synergists, piperonyl butoxide and propargyl propyl benzenephosphonate. The minimal lethal dose (MLD) in mol was 8.9 for the divalent compound alone, which was 4 times larger than that of the corresponding chloropyridyl-based dimer. The MLD was 34 nmol for the trivalent compound, somewhat larger than for the divalent 1,3-xylenyl analog (20 nmol). The synergists combined enhanced their effectiveness about 8–20 times. Neurophysiological measurements were conducted using a nerve preparation containing the abdominal fifth and sixth ganglia of an American cockroach. The trivalent compound showed a pattern characteristic of neonicotinoids and its neuroblocking potency was 100 µM. © Pesticide Science Society of Japan
