SYNTHESIS AND INSECTICIDAL ACTIVITY OF ACYCLIC NITROETHENE COMPOUNDS CONTAINING (6-SUBSTITUTED)-3-PYRIDYLAMINO GROUP

Modification of 1-methylamino-l-[N-methyl-N-(3-pyridylmethyl)]amino-2-nitroethene (1) was progressed stepwise with reference to the insecticidal activities of compounds prepared so far against Nilaparvata lugens. Firstly, we replaced the methylene of 1 with a chemical bond (3), an ethylidene (4) or an ethylene (5), and found that the activity of 1-methylamino-l-[N-methyl-N-(3-pyridyl)]amino-2-nitroethene (3) was higher than others and comparable to 1. Secondly, introduction of a methyl (6), a methoxy (7) or a chloro group (8) into the 6-position of the pyridine of 3 afforded 1-[N-(6-chloro-3-pyridyl)-N-methyl]amino-1-methylamino-2-nitroethene (8) as the best among the compounds derived. Finally, substitution of either one or both of the methyl groups of 8 with a hydrogen or higher alkyls (9-15) or formylation of 8 gave rise to 1-[N-(6-chloro-3-pyridyl)-N-methyl]amino-l-(N-formyl-N-methyl)amino-2-nitroethene (17) as the top of the derivatives which exhibited potent activity against not only N. lugens but also Spodoptera litura.