Butylated Hydroxytoluene (BHT) and p-Coumaric Acid Conjugates of Dipeptide Proline and GABA as Multi-Functional...

Oxidative stress and inflammation are interconnected pathological processes involved in the progression of neurodegenerative, cardiovascular, and metabolic diseases, highlighting the need for multifunctional therapeutic agents targeting multiple pathways. In this study, two novel hybrid compounds were designed and synthesized in three steps by conjugating butylated phenolic moieties derived from butylated hydroxytoluene and p-coumaric acid with proline and γ-aminobutyric acid (GABA). The aim was the combination of antioxidant, anti-inflammatory, and cytoprotective properties within a single molecular framework. The compounds were evaluated using a comprehensive panel of in vitro and in vivo assays to assess antioxidant, metal-reducing, iron-chelating, antiglycation, anti-inflammatory, and acetylcholinesterase inhibitory activities. Both compounds exhibited significant antioxidant activity, with compound 2 demonstrating superior radical scavenging ability against DPPH, ABTS·⁺ and hydrogen peroxide (IC₅₀ 86 μM, 25 μM and 104 μM, respectively), enhanced ferric-reducing capacity (up to 91% of trolox activity), and strong iron-chelating activity (61.3%). Compound 2 also showed potent inhibition of lipid peroxidation (IC₅₀ 17.5 μM) and moderate antiglycation effects (44%), indicating substantial cytoprotective potential. Furthermore, both compounds selectively inhibited COX-2 over COX-1 and demonstrated moderate lipoxygenase inhibition, while compound 2 exhibited significant in vivo anti-inflammatory activity (53%), exceeding that of ibuprofen. Moderate acetylcholinesterase inhibition was also observed. In summary, the results confirm the design rationale, indicating that compound 2 could be further optimized as a multi-targeting molecule directed against oxidative stress- and inflammation-mediated conditions.