Phenyl phthalazine derivative, method for the preparation thereof, and pharmaceutical composition comprising the same

A compound represented by the following Chemical Formula 1, or a pharmaceutically acceptable salt thereof:

• in Chemical Formula 1,
• X is CH, or N,
• L1 is a single bond, C1-4 alkylene, C2-4 alkenylene, NH, O, or SO2,
• L2 is a single bond, C1-4 alkylene, —O—(C1-4 alkylene)-, —(C1-4 alkylene)-O—, CO, NH, NHCO, O, OCO, SO2, or COCHNH2,
• L3 is a single bond, or —O—,
• A is N, or a 5- to 9-membered heterocycloalkane ring or heterobicycloalkane ring containing one or two nitrogen atoms,
• R1 is hydrogen, C1-4 alkyl, C1-4 alkyl substituted with carboxy group, C1-4 haloalkyl, C1-4 alkoxy, C1-4 haloalkoxy, halogen, cyano, nitro, 4-methylpiperazin-1-carbonyl, carboxy, morpholino, (C1-4 alkyl)sulfonyl, (piperidinyl)sulfonyl, or (piperazinyl)sulfonyl,
• R2 is C1-5 alkyl unsubstituted or substituted with amino, carboxy, —COO(C1-4 alkyl), —CONH2, benzyloxy, or imidazole;
• C3-6 cycloalkyl unsubstituted or substituted with amino;
• amino;
• NH(C1-4 alkyl);
• N(C1-4 alkyl)2;
• hydroxy;
• carboxy;
• —COO(C1-4 alkyl);
• phenyl;
• or a 5- or 6-membered heterocyclic group containing 1 to 3 heteroatoms each independently selected from the group consisting of N, O and S,
• R3 is hydrogen, or C1-4 alkyl,
• R4 is hydrogen, or halogen, and
• n is 1 or 2, provided that when A is N, n is 1.