Tsikolia Maia, Bernier Ulrich R, Coy Monique R, Chalaire Katelyn C, Becnel James J, Agramonte Natasha M, Tabanca Nurhayat, Wedge David E, Clark Gary G, Linthicum Kenneth J, Swale Daniel R, Bloomquist Jeffrey R
U.S. Department of Agriculture-Agricultural Research Service, Center for Medical, Agricultural, and Veterinary Entomology, Gainesville, FL 32608, USA.
U.S. Department of Agriculture-Agricultural Research Service, Center for Medical, Agricultural, and Veterinary Entomology, Gainesville, FL 32608, USA.
Pestic Biochem Physiol. 2013 Sep;107(1):138-47. doi: 10.1016/j.pestbp.2013.06.006. Epub 2013 Jun 18.
Twenty trifluoromethylphenyl amides were synthesized and evaluated as fungicides and as mosquito toxicants and repellents. Against Aedes aegypti larvae, N-(2,6-dichloro-4-(trifluoromethyl)phenyl)-3,5-dinitrobenzamide (1e) was the most toxic compound (24 h LC50 1940 nM), while against adults N-(2,6-dichloro-4-(trifluoromethyl)phenyl)-2,2,2-trifluoroacetamide (1c) was most active (24 h LD50 19.182 nM, 0.5 μL/insect). However, the 24 h LC50 and LD50 values of fipronil against Ae. aegypti larvae and adults were significantly lower: 13.55 nM and 0.787 × 10(-4) nM, respectively. Compound 1c was also active against Drosophila melanogaster adults with 24 h LC50 values of 5.6 and 4.9 μg/cm(2) for the Oregon-R and 1675 strains, respectively. Fipronil had LC50 values of 0.004 and 0.017 μg/cm(2) against the two strains of D. melanogaster, respectively. In repellency bioassays against female Ae. aegypti, 2,2,2-trifluoro-N-(2-(trifluoromethyl)phenyl)acetamide (4c) had the highest repellent potency with a minimum effective dosage (MED) of 0.039 μmol/cm(2) compared to DEET (MED of 0.091 μmol/cm(2)). Compound N-(2-(trifluoromethyl)phenyl)hexanamide (4a) had an MED of 0.091 μmol/cm(2) which was comparable to DEET. Compound 4c was the most potent fungicide against Phomopsis obscurans. Several trends were discerned between the structural configuration of these molecules and the effect of structural changes on toxicity and repellency. Para- or meta- trifluoromethylphenyl amides with an aromatic ring attached to the carbonyl carbon showed higher toxicity against Ae. aegypti larvae, than ortho- trifluoromethylphenyl amides. Ortho- trifluoromethylphenyl amides with trifluoromethyl or alkyl group attached to the carbonyl carbon produced higher repellent activity against female Ae. aegypti and Anopheles albimanus than meta- or para- trifluoromethylphenyl amides. The presence of 2,6-dichloro- substitution on the phenyl ring of the amide had an influence on larvicidal and repellent activity of para- trifluoromethylphenyl amides.
合成了20种三氟甲基苯基酰胺，并对其作为杀菌剂、蚊虫毒剂和驱避剂进行了评估。对于埃及伊蚊幼虫，N-(2,6-二氯-4-(三氟甲基)phenyl)-3,5-二硝基苯甲酰胺(1e)是毒性最强的化合物(24小时半数致死浓度为1940 nM)，而对于成虫，N-(2,6-二氯-4-(三氟甲基)phenyl)-2,2,2-三氟乙酰胺(1c)活性最高(24小时半数致死剂量为19.182 nM，0.5 μL/昆虫)。然而，氟虫腈对埃及伊蚊幼虫和成虫的24小时半数致死浓度和半数致死剂量值显著更低：分别为13.55 nM和0.787×10(-4) nM。化合物1c对黑腹果蝇成虫也有活性，对于俄勒冈-R和1675品系，其24小时半数致死浓度值分别为5.6和4.9 μg/cm²。氟虫腈对黑腹果蝇的这两个品系的半数致死浓度值分别为0.004和0.017 μg/cm²。在针对雌性埃及伊蚊的驱避生物测定中，2,2,2-三氟-N-(2-(三氟甲基)phenyl)乙酰胺(4c)具有最高的驱避效力，最低有效剂量(MED)为0.039 μmol/cm²，而避蚊胺的最低有效剂量为0.091 μmol/cm²。化合物N-(2-(三氟甲基)phenyl)己酰胺(4a)的最低有效剂量为0.091 μmol/cm²，与避蚊胺相当。化合物4c是对暗拟茎点霉最有效的杀菌剂。在这些分子的结构构型与结构变化对毒性和驱避性的影响之间发现了一些趋势。羰基碳上连接有芳环的对-或间-三氟甲基苯基酰胺对埃及伊蚊幼虫的毒性高于邻-三氟甲基苯基酰胺。羰基碳上连接有三氟甲基或烷基的邻-三氟甲基苯基酰胺对雌性埃及伊蚊和白纹伊蚊产生的驱避活性高于间-或对-三氟甲基苯基酰胺。酰胺苯环上2,6-二氯取代的存在对三氟甲基苯基酰胺的杀幼虫和驱避活性有影响。
