The present invention provides an isoquinoline-6-sulfonamide derivative that is useful as a novel pharmaceutical agent. The present invention provides an isoquinoline-6-sulfonamide derivative represented by Formula (1), a salt thereof, or a solvate of the derivative or the salt: wherein X and Y each independently represent a direct bond, NH, CH=CH, O, or S； R 1 and R 2 each independently represent a hydrogen atom, a halogen atom, a cyano group, an alkyl group, or the like； R 3 and R 4 each independently represent a hydrogen atom, an alkyl group, or the like, or R 3 and R 4 together form an alkylene group or an alkenylene group, which may be bridged between two carbon atoms to an arbitrary position； and 1, m, and n represent an integer number of 1 to 4.本發明提供一種作為新的醫藥而有用之異喹啉-6-磺醯胺衍生物。本發明係一種以通式(1)所表示之異喹啉-6-磺醯胺衍生物、其鹽或其等之溶劑合物：(式中，X、Y分別獨立，表示直接鍵結、NH、CH=CH、O或S；R1及R2分別獨立，表示氫原子、鹵素原子、氰基、烷基等；R3及R4分別獨立，表示氫原子、烷基等，或者R3與R4亦可一起形成伸烷基或伸烯基，而對任意位置之2個碳間進行交聯；l、m及n表示1~4之數)。
