Biological evaluation of N-aryl-4-aryl-1, 3-thiazole-2-amine derivatives was examined for anti-inflammat ory activity in in vitro and in vivo assays. The thiazole compounds showed direct inhibition of 5-li poxygenase (LOX) that is a key enzyme of leukotrienes synthesis and involved in the inflammationrelated diseases, including asthma and rheumatoid arthritis. To optimize biological activity, we synthesized 1, 3-thiazole-2-amine derivatives and ...