To provide a therapeutic agent for diseases associated with Nav 1.7, specifically diseases such as neuropathic pain, nociceptive pain, inflammatory pain, small fiber neuropathy, erythromelalgia, paroxysmal extreme pain disorder, urination disorders and multiple sclerosis. Provided is a compound represented by formula (I) or a pharmaceutically acceptable salt thereof. (In the formula, each of R1a, R1b, R1c and R1d represents a hydrogen atom, a halogen atom, a cyano group, a C1-4 alkyl group, a C1-4 alkoxy group or the like, provided that at least one of the R1a, R1b, R1c and R1d moieties represents a C6-10 aryl group, a C6-10 aryloxy group or the like； each of R2 and R3 represents a hydrogen atom, a C1-6 alkyl group, a C3-10 cycloalkyl group or the like； R4 represents a hydrogen atom, a C1-6 alkyl group, a C3-7 cycloalkyl group or the like； m represents 1, 2 or 3； L represents a CR7R8 group； and each of R7 and R8 represents a hydrogen atom, a hydroxyl group, a C1-4 alkyl group, a C1-4 alkoxy group or the like.)
