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ARS Home » Southeast Area » Gainesville, Florida » Center for Medical, Agricultural and Veterinary Entomology » Mosquito and Fly Research » Research » Publications at this Location » Publication #356036

Research Project: Biting Arthropod Surveillance and Control

Location: Mosquito and Fly Research

Title: Insecticidal and repellent properties of novel trifluoromethylphenyl amides III

Author
item TSIKOLIA, MAIA - University Of Florida
item Bernier, Ulrich
item AGRAMONTE, NATASHA - University Of Florida
item ESTEP, ALDEN - Navy Entomology Center Of Excellence, Cmave Detachment
item Becnel, James
item Linthicum, Kenneth - Ken
item BLOOMQUIST, JEFREY - University Of Florida

Submitted to: Pesticide Biochemistry and Physiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/22/2019
Publication Date: 6/29/2019
Citation: Tsikolia, M., Bernier, U.R., Agramonte, N.M., Estep, A.S., Becnel, J.J., Linthicum, K., Bloomquist, J.R. 2019. Insecticidal and repellent properties of novel trifluoromethylphenyl amides III. Pesticide Biochemistry and Physiology. https://doi.org/10.1016/j.pestbp.2019.06.012.
DOI: https://doi.org/10.1016/j.pestbp.2019.06.012

Interpretive Summary: The goal of this research was to find new pesticides and repellents by synthesizing small candidate molecules with fluorine atoms. This study is a continuation of our previous work on trifluoromethylphenyl amides (TFMPAs) as mosquito insecticides and repellents. We designed and synthesized a third generation of eighteen amides, and in this study we describe the mosquitocidal activity of these new compounds against Ae. aegypti larvae and adults, and repellency against adult female Ae. aegypti mosquitoes. Some of the compounds had insecticidal/larvicidal activity but were not as active as fipronil. Several of the novel compounds were better or comparable to DEET for repellent activity.

Technical Abstract: Insecticidal, larvicidal, and repellent activity against Aedes aegypti mosquitoes of 18 trifluoromethylphenyl amides (TFMPAs) was studied. This is the third generation of compounds designed from active structures of the previous two generations. N-(3,5-Bis(trifluoromethyl)phenyl)-2-chloroacetamide (8f) and N-(3,5-bis(trifluoromethyl)phenyl)-2,2,3,3,3-pentafluoropropanamide (8h) were most active against 1st instar Ae. aegypti larvae with LC50s 125 and 2.5 mM, compared to the published LC50 for fipronil 0.014 'M. The same 8h was most toxic against female Ae. aegypti with LD50 = 2.12 nmol/mg, followed by 8f, and N-(3,5-bis(trifluoromethyl)phenyl)-2,2,2-trifluoroacetamide (8g) with LD50s 4.27 and 4.73 nmol/mg, correspondingly. Compounds N-(2-(trifluoromethyl)phenyl)butyramide (9c), N-(2-(trifluoromethyl)phenyl)pentanamide (9d) and N-(2-(trifluoromethyl)phenyl)hex-5-enamide (9e) were better or comparable to DEET repellents against female Ae. aegypti, with a minimum effective dosage (MED) of repellency 0.026, 0.052, and 0.091 'mol/cm2, correspondingly. Compound 9c was the second most active repellent out of 52 TFMPAs (total amount of compounds from three generations of our continued research) after 2,2,2-trifluoro-N-(2-(trifluoromethyl)phenyl)acetamide (4c) from our previous study.