Synthesis and larvicidal and adult topical activity of some hydrazidehydrazone derivatives against Aedes aegypti

A series of novel hydrazide-hydrazone derivatives weresynthesized and evaluated for their larvicidal and adulttopical activity against Aedes aegypti. The proposedstructures of all the synthesized compounds were confirmedusing elemental analysis, UV, IR, 1H-NMR, 13C-NMR andmass spectroscopy. Compounds 4a-h were screened in larvalbioassays at concentrations of 100, 50 and 25 ppm in a dosedependent manner and data for their mortality was recorded.Among the tested compounds, 1-(4-nitrophenyl)-3-(4-{2-oxo-2-[2-(2-oxo-1,2-dihydro-3H-ylidene)hydrazinyl] ethyl}phenyl)urea (4b) showed noteworthy larvacidal activityagainst Aedes aegypti. Dose-response data of compound 4bshowed LC50 and LC90 values of 30.5 (15.4 – 22.7) and 95.9(73.8 – 139.4) ppm, respectively. Screening of compounds4a-h at four doses by topical bioassay indicated a range ofactivity between 10000 and 1000 ppm.