Compound having effect of inhibiting platelet aggregation and salt thereof, and composition for preventing or treating thrombotic diseases, containing same

A compound represented by the following Formula (I) or (II), or a pharmaceutically acceptable salt or stereoisomer thereof:

• wherein,
• R1 is hydroxy or C1-C10 alkoxy;
• X is N or O;
• R2 is —(CH2)p-5- to 12-membered heterocycle-(CH2)p—C6-C12 aryl, 5- to 12-membered heterocycle, —(CH2)p—NHC(═O)—C6-C12 aryl, —CHR4R5, 5- to 12-membered heteroaryl, C6-C12 aryl, —C6-C12 aryl-O-5- to 12-membered heteroaryl, or —(CH2)p-5- to 12-membered heteroaryl, provided that when R2 is (CH2)p-5- to 12-membered heteroaryl, the heteroaryl is not pyrazine, pyridine or indole, and when R2 is 5- to 12-membered heteroaryl, the heteroaryl is not benzothiazole;
• wherein p is an integer of 1 to 10;
• R4 and R5 are each independently C1-C6 alkoxycarbonyl or —CH2-5- to 12-membered heteroaryl;
• wherein said heterocycle and heteroaryl may contain 1 to 3 heteroatoms selected from N, O and S;
• said aryl can be substituted with 1 to 4 substituents selected from the group consisting of aminocarbonyl, nitro, nitrile, C1-C6 alkylaminocarbonyl, and hydroxy-C1-C6 alkyl and said heterocycle and heteroaryl is substituted with 1 to 4 substituents selected from the group consisting of halogen, oxo, aminocarbonyl, nitro, C1-C6 alkoxy, nitrile, C1-C6 alkylamino carbonyl, hydroxyl, and hydroxyl-C1-C6 alkyl;
• R3 is hydrogen;
• when X is O, R3 does not exist;
• or
• when X is N, X taken together with R2 and R3 may form a 5- to 12-membered heterocycle containing 1 to 3 heteroatoms selected from O, N and S;
• wherein said heterocycle can be substituted with C6-C12 aryl;
• a 6- to 12-membered heteroaryl containing 1 to 3 heteroatoms selected from O, N and S, which is unsubstituted or substituted with halogen;
• or —O—CHR6R7;
• and wherein R6 and R7 are each independently C6-C12 aryl or a 6- to 10-membered heteroaryl containing 1 to 3 heteroatoms selected from N, O and S, both of which are unsubstituted or substituted with halogen,
• provided that when X is N, X taken together with R2 and R3 forms a 6-membered heterocycle, said heterocycle is substituted with C6-C12 aryl;
• a 6- to 12-membered heteroaryl containing 1 to 3 heteroatoms selected from O, N, and S, which is unsubstituted or substituted with halogen or —OCHR6R7.