Thiazolobenzoimidazole derivatives

A thiazolobenzoimidazole derivative represented by the following general formula (I) or a salt thereof

• wherein each of the symbols is defined as follows
• R1:
• (1) —A1—CO—N(R6)—R7, or
• (3) —A1—CO—A3—N(R6)—R7,
• A1:
• a bond,
• R6 and R7:
• the same or different from each other and each represents hydrogen, —N(R15)—R16, a lower alkyl which may be substituted, a cycloalkyl which may be substituted or a hetero ring which may be substituted and may have bridge(s),
• with the proviso that R6 and R7, together with the adjacent nitrogen atom, may form a hetero ring which may have a substituent and other hetero atom(s), and
• when R1 is —A1—CO—N(R6)—R7, R2 is methyl, A1 is a bond, and one of R6 and R7 is a hydrogen, the other is not n-propyl substituted by nicotinamide,
• R15 and R16:
• the same or different from each other and each represents hydrogen, —CO-lower alkyl, —CO-halo-lower alkyl or —COOR14,
• A3:
• a lower alkylene group which may be substituted by hydroxyl group(s),
• R2:
• hydrogen, a lower alkyl, a halo-lower alkyl, a hydroxy-lower alkyl, a lower alkyl-O-lower alkyl, an amino-lower alkyl or a (mono-or di-lower alkyl-amino)-lower alkyl group, R3, R4 and R5:
• the same or different from one another and each represents hydrogen, a halo, a lower alkyl, a halo-lower alkyl, an N3-lower alkyl, a hydroxy-lower alkyl, hydroxy, a lower alkyl-O—, cyano, —COOR14, acyl, a formyl-lower alkyl, an acyl-O—, an acyl-O-lower alkyl, nitro, —A4—N(R12)—(R13), —SO3H or —A5—O—A4—N(R12)—(R13) group,
• R12 and R13:
• the same or different from each other and each represents hydrogen, a —CO—lower alkyl-N(R15)—R16, a —CO-halo-lower alkyl group, a lower alkyl which may be substituted or a hetero ring group which may be substituted,
• with the proviso that R12 and R13, together with the adjacent nitrogen atom, may form a hetero ring which may have a substituent and other hetero atom(s), and
• when R12 and R13 are hydrogen at the same time, A4 is other than a bond, R14:
• hydrogen or a lower alkyl group,
• A4:
• a bond or a lower alkylene group which may be substituted by hydroxyl group(s), and A5:
• a bond or a lower alkylene group.