Bicyclic compound

A compound represented by the following formula (1) or a salt thereof:

• wherein:
• A represents a group selected from the group consisting of (1) a saturated heterocyclic group, (2) a 5-membered heteroaromatic group having two heteroatoms in the ring which may be substituted, (3) a group represented by the following formula A1, (4) a group represented by the following formula A2, and (5) a group represented by the following formula A3:
• in which
• R2, R3, and R4 may be the same or different, and independently represent a hydrogen atom, a hydroxyl group, a halogen atom, an alkyl group, a phenyl group, a substituted phenyl group, a benzyl group, a substituted benzyl group, a monocyclic heteroaromatic group which may be substituted, a bicyclic heteroaromatic group which may be substituted, an alkoxyl group, an alkyl group arbitrarily substituted with one or more halogen atoms, an alkoxyl group arbitrarily substituted with one or more halogen atoms, a nitro group, or N (R16) (R17), wherein R16 and R17 may be the same or different, and independently represent a hydrogen atom, an alkyl group, an acyl group, or SO2R18, wherein R18 represents a lower alkyl group, or R16 and R17 together form a 3- to 7-membered ring to represent a cyclic amine as N (R16) (R17);
• R5, R6 and R7 may be the same or different, and independently represent a hydrogen atom, a hydroxyl group, a halogen atom, an alkyl group, a phenyl group, a substituted phenyl group, a benzyl group, a substituted benzyl group, a monocyclic heteroaromatic group which may be substituted, a bicyclic heteroaromatic group which may be substituted, an alkoxyl group, an alkyl group arbitrarily substituted with one or more halogen atoms, an alkoxyl group arbitrarily substituted with one or more halogen atoms, a nitro group, or N (R16) (R17), wherein R16 and R17 may be the same or different, and independently represent a hydrogen atom, an alkyl group, an acyl group, or SO2R18, wherein R18 represents a lower alkyl group, or R16 and R17 together form a 3- to 7-membered ring to represent a cyclic amine as N (R16) (R17);
• R8, R9 and R10 independently represent a hydrogen atom, a hydroxyl group, a halogen atom, an alkyl group, a phenyl group, a substituted phenyl group, a benzyl group, a substituted benzyl group, a monocyclic heteroaromatic group which may be substituted, a bicyclic heteroaromatic group which may be substituted, an alkoxyl group, an alkyl group arbitrarily substituted with one or more halogen atoms, an alkoxyl group arbitrarily substituted with one or more halogen atoms, a nitro group, or N (R16) (R17), wherein R16 and R17 may be the same or different, and independently represent a hydrogen atom, an alkyl group, an acyl group, or SO2R18, wherein R18 represents a lower alkyl group, or R16 and R17 together form a 3- to 7-membered ring to represent a cyclic amine as N (R16) (R17), or R8 and R9 may together form a benzene ring to represent a bicyclic heteroaromatic group as the group represented by the formula A3;
• X1 represents oxygen atom, sulfur atom, or N—R19 wherein R19 represents a hydrogen atom, an alkyl group, phenyl group, or a substituted phenyl group;
• B is a group represented by the formula B2:
• wherein R12 represents a hydrogen atom or an alkyl group, Y2 represents CH or a nitrogen atom;
• R1 represents an alkyl group;
• and
• n represents an integer of 2 to 6.