A compound or a salt thereof, represented by Formula below: wherein: - - - - - - is a single bond or a double bond; X is -O-, -CH 2 -, or -CH=; Y is -NH- or -O-; R 1 is hydrogen, fluorine, a hydroxy group, a cyano group, or an amino group; R 2 is hydrogen, fluorine, a hydroxy group, a cyano group, or an amino group; R 3 is a vinylene group, an ethynylene group, a C6-C14 arylene group, or a monocyclic or bicyclic heteroarylene group having at least one heteroatom selected from the group consisting of N, S, and O; R 4 is a bond, a methylene group, or a C3-C7 cycloalkylidene group; R 5 is a C3-C7 saturated cycloalkyl group that may have one or more R 6, a C6-C10 unsaturated cycloalkyl group that may have one or more R 6, or a monocyclic or bicyclic unsaturated heterocycloalkyl group that has at least one heteroatom selected from the group consisting of N, S, and O, and that may have one or more R 6; R 6 is halogen, a hydroxy group, a cyano group, a C1-C6 alkyl group that may have one or more phenoxy group as a substituent, a carbamoyl group, a C1-C6 alkoxycarbonyl group, a monocyclic or bicyclic unsaturated heterocycloalkyl group having at least one heteroatom selected from the group consisting of N, S, and O, a monocyclic or bicyclic saturated heterocycloalkyl group that has at least one heteroatom selected from the group consisting of N, S, and O, and that may have one or more of either halogen, hydroxy group, carboxyl group, or C1-C6 alkyl group as a substituent, an amino group, a mono- or di-(C1-C4 alkyl) amino group that may have one or more hydroxy group or phenyl group as a substituent, a C1-C6 alkoxy group that may have one or more of either halogen, C3-C7 saturated cycloalkyl group, or monocyclic or bicyclic unsaturated heterocycloalkyl group having at least one heteroatom selected from the group consisting of N, S, and 0 as a substituent, a benzyloxy group that may have one or more carbamoyl group as a substituent, a C1-C6 alkylthio group, a C1-C6 alkylsulfonyl group, or an aminosulfonyl group, when two or more R 6 are present, the plurality of R 6 may be the same or different. - - - - - - is a single bond or a double bond; X is -O-, -CH 2 -, or -CH=; Y is -NH- or -O-; R 1 is hydrogen, fluorine, a hydroxy group, a cyano group, or an amino group; R 2 is hydrogen, fluorine, a hydroxy group, a cyano group, or an amino group; R 3 is a vinylene group, an ethynylene group, a C6-C14 arylene group, or a monocyclic or bicyclic heteroarylene group having at least one heteroatom selected from the group consisting of N, S, and O; R 4 is a bond, a methylene group, or a C3-C7 cycloalkylidene group; R 5 is a C3-C7 saturated cycloalkyl group that may have one or more R 6, a C6-C10 unsaturated cycloalkyl group that may have one or more R 6, or a monocyclic or bicyclic unsaturated heterocycloalkyl group that has at least one heteroatom selected from the group consisting of N, S, and O, and that may have one or more R 6; R 6 is halogen, a hydroxy group, a cyano group, a C1-C6 alkyl group that may have one or more phenoxy group as a substituent, a carbamoyl group, a C1-C6 alkoxycarbonyl group, a monocyclic or bicyclic unsaturated heterocycloalkyl group having at least one heteroatom selected from the group consisting of N, S, and O, a monocyclic or bicyclic saturated heterocycloalkyl group that has at least one heteroatom selected from the group consisting of N, S, and O, and that may have one or more of either halogen, hydroxy group, carboxyl group, or C1-C6 alkyl group as a substituent, an amino group, a mono- or di-(C1-C4 alkyl) amino group that may have one or more hydroxy group or phenyl group as a substituent, a C1-C6 alkoxy group that may have one or more of either halogen, C3-C7 saturated cycloalkyl group, or monocyclic or bicyclic unsaturated heterocycloalkyl group having at least one heteroatom selected from the group consisting of N, S, and 0 as a substituent, a benzyloxy group that may have one or more carbamoyl group as a substituent, a C1-C6 alkylthio group, a C1-C6 alkylsulfonyl group, or an aminosulfonyl group, when two or more R 6 are present, the plurality of R 6 may be the same or different.