Synthesis and evaluation of radioiodinated cyclooxygenase-2 inhibitors as potential SPECT tracers for cyclooxygenase-2 expression

摘要

Although several COX-2 inhibitors have recently been radiolabeled, their potential for imaging COX-2 expression remains unclear. In particular, the sulfonamide moiety of COX-2 inhibitors may cause slow blood clearance of the radiotracer, due to its affinity for carbonic anhydrase (CA) in erythrocytes. Thus, we designed a methyl sulfone-type analogue, 5-(4-iodophenyl)-1-[4-(methylsulfonyl)phenyl]-3-trifluoromethyl-1H-pyrazole (IMTP). In this study, the potential of radioiodinated IMTP was assessed in comparison with a I-125-labeled celecoxib analogue with a sulfonamide moiety (I-125-IATP).