An Efficient One‐Pot Access of Pentoxifylline‐Thiazole Hybrids: Design, Synthesis, and Antioxidant Activity

Abstract An efficient, facile, and one‐pot route has been utilized for the synthesis of a new series of 3,7‐dimethyl‐1‐(5‐(2‐(4‐substitutedphenylthiazol‐2‐yl)hydrazono)hexyl)‐1 H ‐purine‐2,6(3 H ,7 H )‐dione ( 4a – 4j ). The pentoxifylline ( 1 ) as a novel precursor, thiosemicarbazide, and a variety of phenacyl bromides have been employed to generate a newer pentoxifylline‐thiazole adduct using PPA as the green catalyst at reflux conditions to afford a high yield and pure product. All the synthesized compounds were purified using chromatographic methods and characterized by spectroscopic techniques ( 1 H and 13 C NMR, MS, and IR). Antioxidant activity was assessed using a DPPH free radical scavenging assay, and it was observed that compounds with cyano functional groups and electron‐donating groups showed notably higher potency, with IC 50 values around 400 µM, while those with halogens and nitro functional groups displayed moderate efficacy ( IC 50 ≈600 µM). These results were compared to the standard ascorbic acid, which had an IC 50 of 382.54 ± 5.09 µM. Molecular docking was performed on the myeloperoxidase (MPO) enzyme to explore the mechanistic basis of antioxidant activity, providing valuable insights into the thermodynamic interactions that contribute to binding affinity.