PROBLEM TO BE SOLVED: To provide an antimicrobial agent and a skin external preparation that exhibit excellent antimicrobial activity against bacteria causing skin inflammation.SOLUTION: An antimicrobial agent and a skin external preparation include at least one of a compound represented by formula (1) and an isomer thereof as an active ingredient.COPYRIGHT: (C)2014,JPO&INPIT【課題】皮膚の炎症の原因菌に対して優れた抗菌活性を示す抗菌剤、及び皮膚外用剤の提供。【解決手段】式(1)で表される化合物、その異性体の少なくとも1種を有効成分として含有する抗菌剤及び皮膚外用剤。【選択図】なし