The synthesis of 3-(3-aryl-1,2,4-oxadiazol-5-yl)
propionic acids from arylamidoximes and
succinic anhydride under focused
microwave irradiation conditions is described. The new synthetic method furnished the desired products in 2-3 min and good yields. Furthermore, the previously complicated purification procedure has been simplified in a manner which is quick, eco-friendly and
cost-effective. Larvicidal
bioassay and
fungal growth inhibitory tests were performed using several 3-(3-aryl-1,2,4-oxadiazol-5-yl)
propionic acids. These acids presented strong larvicidal activity against L4 larvae of
Aedes aegypti. The results suggest that larvicidal activity might be
correlated with the presence of
electron-withdrawing substituents in the para position of the
phenyl ring except the
fluorine atom. The alterations observed in the larvae spiracular
valves of the
siphon and anal papillae by 1,2,4-oxadiazoles in the larvicidal
bioassay are responsible for larvae's death. Furthermore, all acids inhibited the
fungal growth of five different types of
fungi, viz.,
Fusarium solani, F. oxysporum, F. moniliforme, F. decemcellulare and F. lateritium in a preliminary evaluation. Both of these activities are being disclosed for the first time for 1,2,4-oxadiazole-5-yl ring linked at C-3 of
propionic acid.
