Design, Synthesis and Insecticidal Activity of Novel meta-Diamide Compounds Containing Methoxy Group

This work is based on the precursor compound cyproflanilide and designs a series of methoxy containing meta-diamine compounds. By replacing the fluorine atom on the phenyl ring in cyproflanilide with methoxy group, 17 derivatives (12a-12q) were obtained with yields ranging from 46 to 92%, which were characterized by high-resolution mass spectrometry, and nuclear magnetic resonance (1H and ¹³C) spectroscopy and infrared. The insecticidal activities were evaluated against the Plutella xylostella and Spodoptera frugiperda. Compound N-(3-((2-bromopropane-4-(perfluoropropan-2-yl))-6-(trifluoromethyl)phenyl)methoxyphenyl)-N-(cyclopropylmethyl)-6-fluoronicotinamide (12q) showed significant insecticidal activity against the Plutella xylostella with a mortality rate of 97.67% at a concentration of 1 mg L^-1. It also exhibited moderate activity against the Spodoptera frugiperda at a concentration of 0.1 mg L^-1, which can be used as a template for structure modification to obtain higher insecticidal activity.

Keywords:
methoxy group; meta-diamide compounds; insecticidal activity; structure-activity relationship