Sulfonamide or sulfa drug is a known term used in various classes of medicines. Due to the high efficiency of sulfonamide group in various drugs candidates, it is still used as a vital moiety for the drug syntheses by the medicinal chemists. In this research, we have brominated benzenesulfonamide to get N, N-dibromobenzenesulfonamide. Furthermore, we have checked the comparative activities of both the starting sulfonamide and the brominated product. The anticholinesterase activity was determined with Ellman’s assay. α-Glucosidase inhibitory potential was determined with chromogenic assay. DPPH and ABTS free radicals were used in antioxidant assay. Both benzene sulfonamide and its brominated product showed activities in various concentrations in the in-vitro assays. The acetylcholinesterase and butyrylcholinesterase (AChE & BChE) inhibitions of the brominated product were prominent, i.e., 63.98±1.51% and 67.98±0.07% at highest concentrations with IC50 192.89 and 120.52 µg/ml respectively. The benzene sulfonamide exhibited 61.40±0.21% and 63.06±0.50% at highest concentrations with IC50 241.85 and 190.44 µg/ml respectively. The activity of the positive control galantamine was75.72±0.35% and 77.05±0.13% with IC50 43.30 and 35.06 µg/ml against AChE and BChE respectively. Similarly, in α-glucosidase assay, the brominated product showed excellent activity. Sulfonamide causing 74.62±0.40% while brominated sulfonamide showed 78.61% enzyme inhibition at 1 milligram per milliliter showing IC50 47.70 and 122.40 microgram per milliliter respectively. The Acarbose standard drug exhibited 86.61±0.43% activity with IC50 of 34.39 microgram per milliliter. In the ABTS and DPPH antioxidant assays, the synthesized dibromobenzenesulfonamide exhibited comparable results with sulfonamide i.e., 63.06±0.50% and 67.37±0.26% radicals scavenging at 1 milligram per milliliter having IC50 (µg/ml) of 190.44 and 109.03 respectively. Binding poses were explored by the help of docking simulations. Binding affinity data confirmed the in vitro activity. Our results concluded that in anticholinesterase, α-glucosidase inhibitory and antioxidant the activity can be increased by bromination of benzene sulfonamide.

Mater H. Mahnashi, Bandar A. Alyami, Yahya S. Alqahtani, Ali O. Alqarni, Muhammad Saeed Jan, Muhammad Ayaz, Farhat Ullah, Umer Rashid and Abdul Sadiq