Oxaprozin prodrug as safer nonsteroidal anti-inflammatory drug: Synthesis and pharmacological evaluation

Oxaprozin is a popular non-steroidal anti-inflammatory drug (NSAID) and its chronic oral use is clinically restricted due to its gastrointestinal (GI) complications. In order to circumvent the GI complications, oxaprozin was amended as a prodrug in a one-pot reaction using N,N-carbonyldiimidazole as an activating agent. Dextran of average molecular weight (60,000-90,000 Da) was exploited as a carrier in the process of oxaprozin prodrug production by esterification. The structural profiles of the synthesized oxaprozin prodrug were characterized by FT-IR and NMR spectroscopy. The oxaprozin prodrug possessed optimal molecular weight, lipophilicity, partition coefficient, protein binding, and degree of substitution of 52.4%. The release of oxaprozin upon hydrolysis of the prodrug in both simulated gastric fluid and simulated intestinal fluid followed first-order kinetics with 55.2 min of half-life. Varied ADME properties of the prodrug resulted upon Schrodinger's QikProp tool application. Oxaprozin prodrug displayed significant analgesic, antipyretic, and anti-inflammatory activities, with a remarkable decrease in the ulcer index and being devoid of antigenicity in experimental animals. Thus, it is evident that oxaprozin prodrug is a safer oral NSAID without causing any ulcerations.