6-(2,4-difluorophenoxy)-2-(1,5-dihydroxypentan-3-ylamino)-8-methylpyrido[6,5-d]pyrimidin-7-one 6-(2,4-difluorophenoxy)-2-[[3-hydroxy-1-(2-hydroxyethyl)propyl]amino]-8-methyl-pyrido[6,5-d]pyrimidin-7-one 6-(2,4-difluorophenoxy)-2-[[3-hydroxy-1-(2-hydroxyethyl)propyl]amino]-8-methyl-7-pyrido[6,5-d]pyrimidinone 6-(2,4-difluorophenoxy)-2-(1,5-dihydroxypentan-3-ylamino)-8-methyl-pyrido[6,5-d]pyrimidin-7-one