Location: Mosquito and Fly ResearchTitle: Synthesis and structure-activity relationships of carbohydrazides and 1,3,4-oxadiazole derivatives bearing imidazolidine moiety against the yellow fever and dengue vector, Aedes aegypti Author
|Tok, Faith - University Of Marmara|
|Kocyigit-kaymakciogl, Bedia - University Of Marmara|
|Estep, Alden - Navy Entomology Center Of Excellence, Cmave Detachment|
|Gross, Aaron - University Of Florida|
|Geldenhuys, Werner - West Virginia University|
|Bloomquist, Jeffrey - University Of Florida|
Submitted to: Pest Management Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/4/2017
Publication Date: 10/23/2017
Citation: Tok, F., Kocyigit-Kaymakciogl, B., Tabanca, N., Estep, A.S., Gross, A.D., Geldenhuys, W., Becnel, J.J., Bloomquist, J.R. 2017. Synthesis and structure-activity relationships of carbohydrazides and 1,3,4-oxadiazole derivatives bearing imidazolidine moiety against the yellow fever and dengue vector, Aedes aegypti. Pest Management Science. 74:413–421.
Interpretive Summary: Mosquito-borne diseases are a global problem and a continued threat to public health. Emergence of resistance to the majority of existing compounds has prompted a continued demand for new insecticides. In this study, a series of new oxadiazole derivatives were synthesized and the structures were characterized by elemental analysis. The structure-activity relationship of 17 compounds indicated that activity depends on the functional groups. Thus, it can be concluded that the modifications of several active compounds were effective in increasing mosquito adulticidal activity and may lead to the development of new effective public health pesticides.
Technical Abstract: BACKGROUND: 1,3,4-oxadiazole and imidazolidine rings are important heterocyclic compounds exhibiting a variety of biological activities. In this study, novel compounds with oxadiazole and imidazolidine rings were synthesized from 3-(methylsulfonyl)-2-oxoimidazolidine-1-carbonyl chloride and screened for insecticidal activities. The proposed structures of the 17 synthesized compounds were confirmed using elemental analysis, IR, 1H-NMR, and mass spectroscopy. RESULTS: None of the compounds showed larvicidal activity at the tested concentrations against 1st instar Aedes aegypti larvae. However, nine compounds exhibited promising adulticidal activity with the mortality rates of =80% at 5 'g/mosquito. Further dose-response bioassays were undertaken to determine LD50 values. Compounds 1, 2b, 2c, 2d, 2g, 3b, 3c, 3g, and 3h were effective with LD50s of about 5-10 'g/mosquito against female Ae. aegypti. Compounds 2c, bearing a nitro group on the aromatic ring, (LD50 = 2.80 ± 0.54 'g/mosquito) and 3h (double halogen groups at 2,4 position on the phenyl ring) (LD50 = 2.39 ± 0.15 'g/mosquito) were the most promising compounds. CONCLUSION: Preliminary mode of action studies failed to show find consistent evidence of either neurotoxic or mitochondria-directed effects. Further chemical synthesis within this series may lead to the development of new effective insecticides.