Oxadiazole compound and preparation method thereof, pharmaceutical composition and use thereof

An oxadiazole compound having anti-cosxackie-viruses as represented by formula (I) or pharmaceutically acceptable salt thereof,

• Y is alkyl, unsubstituted cycloalkyl, mono-substituted cycloalkyl, disubstituted cycloalkyl, poly-substituted cycloalkyl, unsubstituted aryl, mono-substituted aryl, disubstituted aryl, poly-substituted aryl, unsubstituted 5-6 membered heterocyclyl, mono-substituted 5-6 membered heterocyclyl, disubstituted 5-6 membered heterocyclyl, or poly-substituted 5-6 membered heterocyclyl.
• wherein, R is CH3 or CF3,
• R′ and R″ are respectively H, alkyl or halogen;
• A is O or S;
• n=1-6;
• X is O, S or NH;
• Y is alkyl, cycloalkyl, aryl or 5 to 6 membered heterocyclic group;
• wherein the alkyl is C1-C6 alkyl;
• the cycloalkyl is unsubstituted C3˜C10 cycloalkyl, monosubstituted C3˜C10 cycloalkyl, disubstituted cycloalkyl, polysubstituted C3˜C10 cycloalkyl;
• the aryl is unsubstituted phenyl, monosubstituted phenyl, disubstituted phenyl, polysubstituted phenyl;
• the 5 to 6 membered heterocyclic group is unsubstituted thienyl, unsubstituted furyl, unsubstituted pyrrolyl, unsubstituted isoxazolyl, unsubstituted oxazolyl, unsubstituted pyridazinyl, unsubstituted pyrazinyl, unsubstituted thiazolyl, unsubstituted isothiazolyl, unsubstituted triazolyl, unsubstituted tetrazolyl, unsubstituted thiadiazolyl, unsubstituted oxadiazolyl, unsubstituted imidazolyl, unsubstituted pyrazolyl, unsubstituted pyridyl, unsubstituted pyrimidinyl;
• or
• the 5 to 6 membered heterocyclic group is monosubstituted thienyl, monosubstituted furyl, monosubstituted pyrrolyl, monosubstituted isoxazolyl, monosubstituted oxazolyl, monosubstituted pyridazinyl, monosubstituted pyrazinyl, monosubstituted thiazolyl, monosubstituted isothiazolyl, monosubstituted triazolyl, monosubstituted tetrazolyl, monosubstituted thiadiazolyl, monosubstituted oxadiazolyl, monosubstituted imidazolyl, monosubstituted pyrazolyl, monosubstituted pyridyl, mono-substituted pyrimidinyl;
• or
• the 5 to 6 membered heterocyclic group is disubstituted thienyl, disubstituted furyl, disubstituted pyrrolyl, disubstituted isoxazoly, disubstituted oxazolyl, disubstituted pyridazinyl, disubstituted pyrazinyl, disubstituted thiazolyl, disubstituted isothiazolyl, disubstituted triazolyl, disubstituted imidazolyl, disubstituted pyrazolyl, disubstituted pyrimidinyl.