Novel Thiazolotriazolone Derivatives: Design, Synthesis, In Silico Investigation, Analgesic and Anti‐inflammatory Activity

Abstract

AbstractA group of new thiazolo[3,2‐b][1,2,4]triazol‐6(5H)‐one fenamate‐like derivatives designed by using hybrid strategy in order to explore analgesic/anti‐inflammatory activity of the hybrid structures. Some of the synthesized analogs showed comparable activities with mefenamic acid in abdominal constriction test and carrageenan induced rat paw edema test. 5‐(4‐nitrobenzylidene)‐2‐(2‐(2‐chlorophenoxy)phenyl)thiazolo[3,2‐b][1,2,4]triazol‐6(5H)‐one (8 e) and 5‐(3,5‐di‐tert‐butyl‐4‐hydroxybenzylidene)‐2‐(2‐(2‐chlorophenoxy)phenyl)thiazolo[3,2‐b][1,2,4]triazol‐6(5H)‐one (8 k) were determined as the most active agents with 53.1 and 49.3 percent of inhibition after 4 hrs of ip administration respectively. Flexible docking investigation indicated that the designed molecules interacted with cyclooxygenase 1 and 2 (COX‐1 and COX‐2) active sites. Moreover, the results suggest that thiazolo[3,2b][1,2,4]triazol‐6(5H)‐one moiety has the same effect as mefenamic acid COOH group over COX‐1,2 with a significant low or no ulcerogenic activity. Furthermore, the energetically favorable conformer Z, revealed as the active structural conformation due to the less steric hindrance. Based on the predicted ADME properties of high potent anti‐inflammatory agents, it is proposed that the applied modifications promote the rational drug design of novel analgesic and anti‐inflammatory candidates.