In silico and in vitro antioxidant activity profiles of urea and thiourea derivatives of 5-hydroxytryptophan.

A series of new urea and thiourea derivatives of 5-hydroxy tryptophan 3a-l was designed and synthesized from 5-hydroxy tryptophan (1) by treating various isocyanates 2a-g and isothiocyanates 2h-l in the presence of triethylamine (TEA) as a base. The antioxidant activities of the newly synthesized compounds were evaluated by using different in vitro assays such as 1, 1-diphenyl-2-picrylhydrazyl (DPPH), hydrogen peroxide (H2O2) and superoxide. The results obtained from the in vitro studies revealed that the compounds 3a, 3g, 3h, and 3l exhibited the significant high content of antioxidant activity. Besides, molecular docking studies indicated that, all the compounds 3a-l have formed higher binding energies with 3MNG protein than the reference compound 1. Among all the synthesized compounds, 3a, 3l, 3g, 3b, 3c and 3h have exhibited the highest dock scores than the rest of the compounds including the reference compound. Hence, it is concluded that the title compounds will open new vistas for the discovery of strong antioxidants and will stand as remarkable antioxidant moieties in future.