Design, synthesis and in vitro evaluation of thiazole derivatives of naproxen as cyclooxygenase-2 inhibitors

Based on the differences between cyclooxygenase-2 (COX-2) and COX-1, a series of derivatives of naproxen in which the carboxyl group was replaced with a variety of substituted thiazolyls were designed. Seven target compounds were synthesized in four steps with naproxen as a starting material and structurally confirmed by H-1 NMR, MS and elemental analysis or HRMS. The biological tests showed that some of them have inhibitory activity against COX-2 in vitro.