Synthesis and bioactivity of 0-ethyl phosphorodiamidates derived from quinazolin-4-ones and either amino acid esters or fatty amines

Abstract

Synthesis of several O-ethyl phosphorodiamidates derived from unsubstituted, or 6-bromo-, or 6-nitro-3-amino-2-methyl-3H-quinazolin-4-one and either amino acid esters or fatty amines is described. These compounds showed high insecticidal activity toward mosquito larvae, with lethal concentrations LC50 and LC90 as low as 0.028 and 1.724 ppm, respectively. The highest activity was observed with those compounds containing both a nitro substituent and a 10-carbon-atom fatty-amine moiety. Multiple regression analysis was used to explain the larvicidal activity variation of these compounds. The larvicidal activity generally decreased according to the following order of amino acid moieties: glutamic acid > methionine > elycine > alanine > phenylalanine. © 1999 John Wiley & Sons, Inc.