Insecticidal and repellent properties of novel trifluoromethylphenyl amides II

Abstract

A B S T R A C TThis project focused on the design, synthesis, and testing of trifluoromethylphenyl amides (TFMPAs) as potential mosquitocides and repellents. Fourteen compounds were evaluated for toxicity against larvae and adults of Aedes aegypti. Several compounds were toxic against Aedes aegypti (larval, adult and feeding bioassays) and Drosophila melanogaster (glass-surface contact assay), but were much less toxic than fipronil, with toxicity ratios ranging from 100-fold in the larval assay to 100,000-fold for topical application to adult insects. In repellency bioassays to determine minimum effective dosage (MED), compound N-(2,6-dichloro-4-(trifluoromethyl)phenyl)-2,2,3,3,3-pentafluoropropanamide (7b) repelled Ae. aegypti females at lower concentration, 0.017 ( ± 0.006) μmol/cm 2 , than N, N-diethyl-meta-toluamide (DEET) 0.026 ( ± 0.005) μmol/cm 2 . 2-Chloro-N-(3-(trifluoromethyl)phenyl)acetamide (6a) performed better than DEET against two species of mosquitoes: it repelled Ae. aegypti females at 0.013 ( ± 0.006) μmol/cm 2 and Anopheles gambiae females (in a warm body repellent assay), at a standard exposure of 2 nmol/cm 2 . These studies revealed novel active structures that could further lead to compounds with better repellent activity.

Chemical composition of the essential oil and n-hexane extract of Stachys tmolea subsp. Tmolea Boiss., an endemic species of Turkey, and their mosquitocidal activity against dengue vector Aesdes aegypti

“…The larvicidal screening assay method used here is designed for use in microplates in order to produce useful information from mg quantity samples of isolated compounds and allows screening of large numbers of individual compounds and has been well published (Pridgeon et al, 2008, Chang et al, 2014, Tsikolia et al, 2018, Shen et al, 2018) samples were tested at concentrations of 1, 0.5, 0.25 and 0.1 μg/μL against 1st instar Ae. aegypti larvae.…”

Diarylamine-Guided Carboxamide Derivatives: Synthesis, Biological Evaluation, and Potential Mechanism of Action

“…Therefore, diarylamines as easily available substrates have proven a convenient choice for construction of structural diversity molecules with promising bioactivity. In addition, carboxamides are also a useful class of molecules with potential pharmacological ( Odingo et al, 2017 ; Tang et al, 2018 ; Barker et al, 2019 ; Ling et al, 2019 ; Sethy et al, 2019 ; Sun et al, 2019 ; Yang et al, 2019 ) and agroactive activities ( Sartori et al, 2018 ; Tsikolia et al, 2018 ; Yu et al, 2018 ; Liu et al, 2019 ; Siber et al, 2019 ; Tsikolia et al, 2019 ; Liu et al, 2020 ), and many carboxamides have been developed as clinical drugs or agrochemicals, which demonstrate that amide units will play an important role in the development of drugs and pesticides.…”

Resistance-Breaking Insecticidal Activity of New Spatial Insecticides against Aedes aegypti

“…The scope of this research focused on the synthesis and screening of a variety of N-arylamides to identify spatially acting mosquitocides that can overcome resistance. Previously reported work from our group identified fluorinated phenyl amides as potent vapor-acting repellents, − and while mosquito repellency is an appealing method of mosquito control, it is not the only one. Bug zappers and mosquito trap work by attracting the insect and inducing mortality through electrical or chemical means.…”