Synthesis of selective COX-2 inhibitors: Novel 1.5-diarylhydantoins via cyclization of methyl $\alpha$-aminoacetates with aralkyl isocyanate

Nonsteroidal antiinflammatory drugs(NSAIDs) are widely used to treat pain. fever and inflammatory condition. But chronic-disease patients suffer from gastro-intestinal disturbances such as discomfort. nausea. peptic ulcer and severe bleeding because NSAIDs inhibit not only COX-2 associated with anti-inflammatory activity but also COX-1 associated with adverse gastro-intestinal effects. On the basis of this fact. specific COX-2 inhibitors such as celecoxib and rofecoxib are introduced in the drug market. (omitted)