Bicycloamine carboxamide derivative

The present invention relates to a compound represented by formula (1) or a pharmaceutically acceptable salt thereof that has therapeutic and prophylactic effects on diseases in which orexin type 2 receptors participate, specifically, narcolepsy, idiopathic hypersomnia, hypersomnia, sleep apnea syndrome, etc. [In the formula: R1 and R2 independently represent a hydrogen atom, etc.; R3 and R4 independently represent a hydrogen atom, etc.; R5 represents optionally substituted C1-4 alkyl; -L1-ring G represents -ring G, -CH2-ring G, etc.; R6s independently represent a hydrogen atom, etc.; n is an integer of 1 or 2; ring G represents an optionally substituted C6-10 aromatic carbocyclic group, etc.; A1 represents an oxygen atom, etc.; A2 represents an oxygen atom, etc.; j, k, l and m are independently an integer of 0, 1 or 2; a broken line represents a single or double bond; X represents -CR7-, etc.; R7 represents a hydrogen atom, etc.; and ring E is represented by formula (1a-1), (1a-2) or (1a-3).].