Synthesis, spectroscopic characterization, molecular docking and theoretical studies (DFT) of N-(4-aminophenylsulfonyl)-2-(4-isobutylphenyl) propanamide having potential enzyme inhibition applications

A mutual prodrug (1) of ibuprofen and sulphanilamide has been synthesized with dual activity and improved toxicity profile. The synthesized compound has been characterized by elemental analysis, FT-IR, ¹HNMR, ¹³CNMR and ESI-MS. The molecular geometry of the compound (1) was optimized using density functional theory (DFT/B3LYP) method with the 6-311G(d,p) basis sets in ground state. Geometric parameters (bond lengths, bond angles, torsion angles), vibrational assignments, chemical shifts and thermodynamics of the compound (1) has been calculated theoretically and compared with the experimental data. Comparative AutoDock study of compound (1) with cyclooxygenase enzymes (COX-1 and COX-2) were performed involving docking for possible selectivity of our prodrug within the two Cox enzymes. The highest binding affinities of −8.7 Kcal/mol and −8.1 Kcal/mol has been obtained for COX-1 and COX-2 enzymes respectively. Compound (1) exhibited enhanced anti-inflammatory, anti-ulcer and free radical scavenging activities as compared with the parent drugs. Based on various in vitro and in vivo tests it is suggested that the Compound (1) is more active than the parent drugs. Moreover, LD₅₀ of compound (1) is higher than parent drug i.e. ibuprofen and sulphanilamide suggesting that the synthesized compound is much safer than its parent analogous.