Synthesis and mosquito repellent properties of 2,2-dialkyl- and 2-alkyl-4,4-dimethyl-N-acetyloxazolidines
Autor(es): Taylor, W. G.; Hall, T. W.; Schreck, C. E.
Resumo: Nineteen novel N-acetyl-2,2-dialkyloxazolidines (2) and N-acetyl-2-alkyl-4,4-dimethyloxazolidines (3) were synthesized from commercially available carbonyl compounds and ethanolamine or 2-amino-2-methyl-1-propanol. Their bioactivity against laboratory-reared mosquitoes was compared in patch tests to known N-acetyl-2-alkyloxazolidines (1) and N,N-diethyl-m-toluamide (deet insect repellent). Isomeric composition measurements by [ super(13)C]NMR spectroscopy favoured the Z rotational isomer for samples of 2 (91-96% Z) and the E rotational isomer for samples of 3 (66-71% E), in agreement with molecular mechanics calculations on rotational isomers of model oxazolidines. Samples of 1 were previously shown to exist in solution mostly as the Z isomer (60-70% Z). Within the optimal molecular weight range for these experimental chemicals, the duration of repellency against Aedes aegypti (L.), Anopheles quadrimaculatus Say and Anopheles albimanus Wiedemann generally followed the order: 1 > 2 > deet > 3. Bioassay data are discussed in relation to the equilibrium populations of rotational isomers for substituted N-acetyloxazolidines.
Palavras-Chave: Molecular structure; Pest control; Repellents; Repellency; Aedes aegypti; Anopheles; Culicidae; Diptera
Imprenta: Pesticide Science, v. 46, n. 4, p. 307-314, 1996.
Descritores: Aedes aegypti - Molecular Structure ; Aedes aegypti - Repellent
Data de publicação: 1996
