The purpose of the present invention is to provide: a compound having anti-HBV activity or a salt thereof； a pharmaceutical composition； an anti-hepatitis B virus agent； a DNA generation inhibitor of a hepatitis B virus； and a hepatitis B surface antigen generation or secretion inhibitor. According to the present invention, provided are a compound or a salt thereof, the compound being represented by general formula [1] (in the formula, R1 represents a substitutable benzothiazolyl group (here, carbon atoms constituting a 6-membered ring of the benzothiazolyl of R1 bond to the nitrogen atom of a pyridine ring)； R2 represents a substitutable C2-6 alkenyl group or the like； and R3 represents a hydrogen atom or the like).本發明的課題在於提供一種具有抗HBV活性之化合物或其鹽、藥 物組成物、抗B型肝炎病毒劑、B型肝炎病毒的DNA的產生抑制劑、及B型肝炎表面抗原產生抑制劑或分泌抑制劑。依本發明，提供由通式[1]所表示之化合物或其鹽。式中，R1表示可經取代之苯并噻唑基；R2表示可經取代之C2-6烯基等；R3表示氫原子等。其中，構成R1的苯并噻唑基的6員環之碳原子與吡啶酮環的氮原子鍵結。
