Title : Synthesis, characterization and in vitro acaricidal activity of new [1,2,4]triazolo[4,3-b][1,2,4,6]thiatriazine-1,1-dioxides against cattle tick : Hyalomma scupense
A new series of [1,2,4]triazolo[4,3-b][1,2,4,6]thiatriazine-1,1-dioxides (2a-f) were, synthesized, characterized and evaluated for their acaricidal activity against larvae and adults of H. scupense. The synthesis of triazolothiatriazine-1,1-dioxides (2a-f) was carried out. The approach involves a reaction between N-alkyl/aryl-N'-(4H-1,2,4-triazol-3-yl) amidines 1 and Sulfuryl chloride in the presence of pyridine. The structure of the synthesized compounds was confirmed by FTIR spectroscopy, 13CNMR, mass spectra and elemental analyses. Adult immersion test (AIT) was performed to determine the mortality of ticks, inhibition of oviposition and hatching, after synthetic compounds (2a-f) application. Larval packet test (LPT) was performed on larvae produced from collected ticks. All of the tested compounds displayed a potent acaricidal activity. Among the series, compound (2d) represented the most potent ixodicide activity with LC50 values of 0.19 mg/ml as compared to the standard drug amitraz 0.06 mg/ml. Furthermore, after 24h of exposure, the 2d compound caused a high mortality on H. scupense larvae, as it induced 100% mortality at the highest tested concentration (1 mg/ml) followed by (2c), (2b), (2f), (2a) and (2e) (84.27%, 82.67%, 71.10%, 62.78%, 57.44%, respectively) (P<0.001). New heterocyclic compounds [1,2,4]triazolo[4,3-b][1,2,4,6]thiatriazine-1,1-dioxides (2a-f) were synthesized successfully and displayed satisfactory acaracidal properties against larvae and adults of H. scupense.
- Get an idea of the biological valorization of new sulfur heterocycles
- Makes it possible to solve the problem of resistance of certain veterinary parasites against classic treatments.
- The molecules synthesized can be valued by other researchers.