The present invention addresses the problem of providing a tricin derivative having higher antiviral activity. The compound according to the present invention is a compound represented by formula (I) or a salt thereof.(In formula (I), at least one of R<;sup>;1<;/sup>;-R<;sup>;5<;/sup>;represents a fluorine atom, and the rest of R<;sup>;1<;/sup>;-R<;sup>;5<;/sup>;, which are not fluorine atoms, represent a hydrogen atom or a hydroxy group.)