Synthesis, in vitro anthelmintic, and molecular docking studies of novel 5-nitro benzoxazole derivatives

Novel 5-nitro-1, 3-benzoxazole derivatives (2-8) are synthesized from 5-nitro-1,3-benzoxazole-2-thiol 1. The newly synthesized compounds are characterized by analytical H-1 NMR, C-13 NMR, LC-MS mass spectrometry, and elemental analysis. All compounds are screened for in vitro anthelmintic activities. In correlation to in vitro anthelmintic activity, all compounds are subjected to molecular docking studies for the inhibition of beta-tubulin, target protein elite to the parasites. Compounds 1 and 4 have emerged as potent anthelmintic molecules. The binding energy and hydrogen bonds formed with the surrounding amino acids are in good agreement with predicted binding affinities obtained by molecular docking studies as verified by anthelmintic studies. The compound 5 has showed minimum binding energy with a hydrogen bond, and molecules 1, 4, 6, and 7 have good affinity toward the active pocket with two or more hydrogen bonds respectively, thus they may be considered as good inhibitor of beta-tubulin.