Biaryl urea derivative or salt thereof and preparation process and use for the same

A method for inhibiting RORγt activity in a subject, comprising administering to the subject in need thereof a therapeutically effective amount of the compound shown by formula II or a pharmaceutically acceptable salt thereof:

• wherein:
• B is phenyl or pyridyl;
• R1 is optionally selected from a group consisting of hydrogen, methyl, halogen, cyano, hydroxyl, —CF3, —CHF2, and —CH2F;
• R1′ is selected from a group consisting of hydrogen, —OCF3, —OCHF2, —CF3 and heteroaryl;
• R2 is optionally selected from a group consisting of hydrogen, halogen, cyano, hydroxyl, C1-C6 alkyl, halogen-substituted C1-C6 alkyl, C(O)ORa or cycloalkyl substituted C1-C6 alkyl, C3-C6 cycloalkyl, C3-C6 oxo(azo)heterocycloalkyl, C1-C6 alkoxyl, halogen-substituted C1-C6 alkoxyl, hydroxyl or C1-C3 alkoxyl substituted C1-C3 alkyl, phenyl, substituted heteroaryloxyl, C2-C6 alkenyl, halogen substituted aromatic ketone group, carboxyl or cyano substituted heteroaryl, —C(O)Ra, —(CH2)nNRa1Ra2, —(CH2)nC(O)ORa, —C(O)NRa1Ra2;
• R3 and R4 is hydrogen or C1-C3 alkyl;
• R5 and R6 is hydrogen, C1-C3 alkyl or C1-C3 alkyl hydroxyl;
• R7 is optionally selected from a group consisting of hydrogen, halogen, cyano, hydroxyl, C1-C6 alkyl, halogen-substituted C1-C6 alkyl, C(O)ORa or cycloalkyl substituted C1-C6 alkyl, C3-C6 cycloalkyl, C3-C6 oxo(azo)heterocycloalkyl, C1-C6 alkoxyl, halogen-substituted C1-C6 alkoxyl, hydroxyl or C1-C3 alkoxyl substituted C1-C3 alkyl, phenyl, substituted phenyl, phenoxyl, substituted phenoxyl, heterocyclyl, heterocyclooxyl, heteroaryl, heteroaryloxyl, C2-C6 alkenyl, halogen-substituted aromatic ketone group, carboxyl or cyano substituted heteroaryl, —C(O)Ra, —(CH2)nNRa1Ra2, —(CH2)nC(O)ORa and —C(O)NRa1Ra2;
• Y is a covalent bond,
• When R8 is
• wherein Z is O, and R9 is methyl, ethyl, or —NH2;
• or
• Y is —CRa1CRa2, R8 is
• Ra, Ra1 and Ra2 are each independently selected from hydrogen or C1-C3 alkyl;
• m, r, t and n are each independently selected from any integer value of 0˜2.