Coumarin　moiety　has　garnered　momentous　attention　especially　in　the　design　of　compounds　with　significant　biological　activities.　In　this　work,　a　series　of　3-substituted　coumarin　derivatives　6a-6l　were　synthesized　and　fully　characterized.　Most　of　the　compounds　could　obviously　inhibit　the　activity　of　cyclooxygenase-1　(COX-1)　at　the　concentration　of　10µM.　Besides,　6h　and　6l　exhibited　highest　inhibitory　effects　against　COX-2　with　inhibition　rates　of　33.48　and　35.71%,　respectively.　Detailed　structure-activity　relationships　(SARs)　were　also　discussed.　In　vivo　studies,　6b,　6i　and　6l　could　remarkably　repress　the　xylene-induced　ear　swelling　in　mice　at　the　dose　of　20mg/kg.　Especially,　6l　seemed　to　be　the　most　effective　compound　at　the　dose　of　10mg/kg,　displaying　favorable　anti-inflammatory　activity　comparable　to　indomethacin.　All　of　these　findings　suggested　that　6l　might　be　utilized　as　a　candidate　for　the　treatment　of　inflammatory　diseases.　©　2020　The　Pharmaceutical　Society　of　Japan