Problem to be solved: to provide a pyrazine compound or a salt that shows superior control activity against various harmful organisms.Solution: the derivative of the compound which is obtained by directly connecting pyridine to pyrazine represented by the formula (1a) in the following formula.No selection【課題】種々の有害生物に対してより優れた防除活性を示す、ピラジン化合物又は、その塩の提供。【解決手段】下記スキームで式(1a)で表されるピラジンにピリジンが直接結合した構造を取る化合物の誘導体。【選択図】なし