Novel compound as protein kinase inhibitors

A compound of the following Formula 1 or a pharmaceutically acceptable salt thereof:

• in Formula 1,
• L is a direct linkage, O or NR4,
• R1 is hydrogen, C1-C6 alkyl, substituted C1-C6 alkyl, C5-C7 aryl, or substituted C5-C7 aryl, where a substituent of the substituted C1-C6 alkyl and the substituted C5-C7 aryl is selected from the group consisting of C1-C6 alkyl, C6-C10 aryl, halogen, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 alkylthio, hydroxy, —COOH, C1-C6 alkylcarbonyl, C1-C6 alkyloxycarbonyl, C1-C6 alkylcarbonyloxy, —NH2, carbamoyl, urea and —SH,
• R2 is hydrogen, C1-C6 alkyl or substituted C1-C6 alkyl, where a substituent of the substituted C1-C6 alkyl is selected from the group consisting of C1-C6 alkyl, C6-C10 aryl, halogen, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 alkylthio, hydroxy, —COOH, C1-C6 alkylcarbonyl, C1-C6 alkyloxycarbonyl, C1-C6 alkylcarbonyloxy, —NH2, carbamoyl, urea and —SH,
• R3 is hydrogen, halogen, C1-C6 alkyl or substituted C1-C6 alkyl, where a substituent of the substituted C1-C6 alkyl is selected from the group consisting of C1-C6 alkyl, C6-C10 aryl, halogen, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 alkylthio, hydroxy, —COOH, C1-C6 alkylcarbonyl, C1-C6 alkyloxycarbonyl, C1-C6 alkylcarbonyloxy, —NH2, carbamoyl, urea and —SH,
• R4 is hydrogen, C1-C6 alkyl or substituted C1-C6 alkyl, where a substituent of the substituted C1-C6 alkyl is selected from the group consisting of C1-C6 alkyl, C6-C10 aryl, halogen, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 alkylthio, hydroxy, —COOH, C1-C6 alkylcarbonyl, C1-C6 alkyloxycarbonyl, C1-C6 alkylcarbonyloxy, —NH2, carbamoyl, urea and —SH,
• X is hydrogen, C1-C6 alkyl, substituted C1-C6 alkyl, or halogen, where a substituent of the substituted C1-C6 alkyl is selected from the group consisting of C1-C6 alkyl, C6-C10 aryl, halogen, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 alkylthio, hydroxy, —COOH, C1-C6 alkylcarbonyl, C1-C6 alkyloxycarbonyl, C1-C6 alkylcarbonyloxy, —NH2, carbamoyl, urea and —SH,
• A is 5-member to 7-member, substituted or unsubstituted heteroaryl containing 1 to 3 heterocycle-forming atoms selected from the group consisting of nitrogen, sulfur and oxygen, or 3-member to 7-member, substituted or unsubstituted cycloalkyl, where a substituent of the substituted heteroaryl and the substituted cyclolakyl is hydrogen, halogen, C1-C6 alkyl, substituted C1-C6 alkyl, C3-C6 cycloalkyl, C1-C5 alkoxy, 5-member to 12-member aryl, substituted 5-member to 12-member aryl, 5-member to 7-member heteroaryl containing 1 to 3 heterocycle-forming atoms selected from the group consisting of nitrogen, sulfur and oxygen, substituted 5-member to 7-member heteroaryl, or oxo,
• B is C1-C6 alkylcarbonyl, C1-C6 alkylimine, N-hydroxy-substituted C1-C6 alkylimine, halogen, 5-member to 7-member monoaryl, substituted 5-member to 7-member monoaryl, 5-member to 7-member heteromonoaryl containing 1 to 3 heterocycle-forming atoms selected from the group consisting of nitrogen, sulfur and oxygen, substituted 5-member to 7-member heteromonoaryl, 9-member to 10-member fused biaryl, substituted 9-member to 10-member fused biaryl, 9-member to 10-member fused heterobiaryl containing 1 to 3 heterocycle-forming atoms selected from the group consisting of nitrogen, sulfur and oxygen, or substituted 9-member to 10-member fused heterobiaryl, where substituents of the substituted monoaryl, heteromonoaryl, biaryl and heterobiaryl are 1 to 3 substituents independently selected from the group consisting of C1-C3 alkyl, halogen, hydroxy, —NH2 and —SH, and
• the halogen is independently selected from the group consisting of F, Cl, Br and I.