abstract |
A compound represented by the formula (1) or a pharmaceutically acceptable salt thereof which has a therapeutic or prophylactic effect on an SNS-related disease such as neuropathic pain. (1) wherein R1 and R2 independently represent an alkyl group having 1 to 4 carbon atoms or the like, or R1 and R2 may together form a 5- to 7-membered ring; n represents a numerical number of 1 to 3; A represents a substituted or unsubstituted aryl group or the like or a formula: -N(R5)R6 (wherein R5 and R6 independently represent a substituted or unsubstituted alkyl group or the like); and R3 and R4 independently represent a substituted or unsubstituted alkyl group or the like, or R3 and R4 may together form a substituted or unsubstituted, saturated or unsubstituted nitrogenated heterocyclic ring, provided that both of R1 and R2 are not a hydrogen atom when R3 and R4 together form a piperidine ring. |