The present invention addresses the problem of providing novel compounds that have T-type voltage-gated calcium channel-blocking activity and are useful particularly in treating pain, chronic kidney disease, and atrial fibrillation. Provided are novel triazinone compounds represented by formula (I) (the various substituents in the formula are defined in detail in the description but R1 denotes a hydrogen atom, C1-C6 alkyl group, etc., E denotes a 7- to 14-membered non-aromatic condensed heterocyclic group, L3 denotes a C1-C6 alkylene group, etc., and D denotes a C6-C14 aryl group that may be substituted, a 5- to 10-membered heteroaryl group that may be substituted, etc.), tautomers or pharmaceutically permissible salts of said compounds, and solvates thereof.本發明係關於以提供一種具有T型電位依賴性鈣通道阻礙活性,特別對於疼痛、慢性腎臟病及心房顫動之治療上有用的新穎化合物作為課題。本發明為提供式(I)(式中之各取代基雖在本文中已詳細定義,但R1表示氫原子或C1-6烷基等,E表示7-14員非芳香族縮合雜環基,L3表示C1-6伸烷基等,D表示可被取代之C6-14芳基或可被取代之5-10員雜芳基等)所示新穎三嗪酮化合物、該化合物的互變異構物或者該醫藥上可被許可之鹽或彼等溶劑合物者。
