Exploring bis-Schiff Bases with Thiobarbiturate Scaffold: In Vitro Urease Inhibition, Antioxidant Properties, and In Silico Studies

Objective: The main objective of this work is to synthesize thiobarbituric acid based bis-Schiff base derivatives and to evaluate their ability to inhibit urease enzyme and DPPH free radical scavenging potential. Methods: Thiobarbituric acid derived bis-Schiff bases (IIIa–IIIi) were synthesized by treating 2,4-dihydroxybenzaldehyde and the starting moiety 1,3-diethyl-2-thiobarbituric acid in ethanol through refluxed followed by treating chloro ethyl acetate in DMF solvent. Subsequently, hydrazine hydrate was added to compound (II), yielding bis-hydrazide in better yield, which was further reacted via refluxed with benzaldehydes in ethanol, catalyzed by acetic acid to yield compounds (IIIa–IIIi) in excellent yields. Results: The resulting compounds were tested to inhibit urease enzyme and DPPH free radical scavenging activity. Among the series, compound (IIId) (IC₅₀ = 16.11 ± 0.92 µM), (IIIc) (IC₅₀ = 19.11 ± 0.55 µM), and (IIIf) (IC₅₀ = 21.01 ± 1.42 µM) were found as promising lead urease inhibitors, stronger than the standard thiourea (IC₅₀ = 21.15 ± 0.32 µM). Moreover, compound (IIIa) (IC₅₀ = 40.21 ± 0.12 µM) was found as the excellent antioxidant agent comparing it with the standard ascorbic acid. Molecular docking study was performed to analyze the most potent compounds against urease enzyme. The results also shows that all compounds had good ADME properties there was no violation found in compounds ranges all are under druglikness criteria. Additional research combining in vivo, toxicological, and computational analyses can offer thorough understandings of the effectiveness, safety, and fundamental mechanisms of action of these potentially beneficial antioxidant substances. Conclusions: These compounds showed tremendous potential as DPPH free radical scavengers and urease enzyme inhibitors. Compound (IIId) demonstrated the greatest suppression of urease enzyme activity, however compound (IIIa) displayed superior antioxidant effects. Additional research, incorporating in vivo, toxicological, and computational examinations, is necessary to thoroughly assess the effectiveness, safety, and fundamental mechanisms of action of these intriguing antioxidant molecules.