Synthesis and biological evaluation of N-aryl-4-aryl-1,3-thiazole-2-amine derivatives as direct 5-lipoxygenase inhibitors.

Biological evaluation of N-aryl-4-aryl-1,3-thiazole-2-amine derivatives was examined for anti-inflammatory activity in in vitro and in vivo assays. The thiazole compounds showed direct inhibition of 5-lipoxygenase (LOX) that is a key enzyme of leukotrienes synthesis and involved in the inflammation-related diseases, including asthma and rheumatoid arthritis. To optimize biological activity, we synthesized 1,3-thiazole-2-amine derivatives and investigated for structure and activity relationship. Especially, N-(3,5-dimethylphenyl)-4-(4-chlorophenyl)-1,3-thiazole-2-amine was shown to have a potent anti-inflammatory activity as a 5-LOX inhibitor.