Pyridine derivatives

A pyridine derivative of the formula (I)

• wherein —R1 represents
• in which R11 is hydrogen, C1-6 alkyl, halogen, hydroxy, C1-12 alkoxy, nitro, amino, C1-6 alkylsulfonylamino, C1-6 alkoxycarbonyl, C1-6 alkylamino, di(C1-6 alkyl)amino, C1-6 alkanoylamino, phenyl C1-6 alkylamino, phenylsulfonylamino, or —O—(CH2)n—R111,
• wherein n represents an integer selected from 0 to 6, and R111 is C2-6 alkenyl, benzoyl, diphenylmethyl, di(C1-6 alkyl)amino, C1-6 alkanoyl, C1-6 alkoxycarbonyl, or a 3 to 10 membered saturated or unsaturated ring having 0 to 3 heteroatoms selected from the group consisting of S, O and N as heteroatoms and is optionally substituted by C1-6 alkyl, mono or di halogen, halogen substituted C1-6 alkyl, nitro, cyano, C1-6 alkoxycarbonyl, phenyl, hydroxy, amino, C1-6 alkylamino, di(C1-6 alkyl)amino, C1-6 alkanoylamino, C1-6 alkoxy, or carbamoyl;
• R2 represents hydrogen or halogen;
• R3 represents hydrogen or 1,2,3,6-Tetrahydro-pyridine,
• —CR31R32R33,
• wherein R31 is hydrogen or C1-6 alkyl,
• R32 is hydrogen, α-aminobenzyl, C1-6 alkyl optionally substituted by one or two substituents selected from the group consisting of hydroxy, amino, amino substituted phenyl, phenyl, halogen substituted phenyl, and C1-6 alkoxysubstituted phenyl, or a 5 to 8 membered saturated ring having 0 to 3 atoms selected from the group consisting of S, O and N as heteroatoms and optionally substituted by C1-6 alkyl, and
• R33 is hydrogen, amino, C1-6 alkoxycarbonylamino, C2-6 alkenyloxycarbonylamino, piperidino-C1-6 alkylcarbonylamino, piperidinyl-C1-6 alkylcarbonylamino, or
• R32 and R33 may form, together with the adjacent carbon atom, a 5 to 8 membered saturated ring having 0 to 3 heteroatoms selected from the group consisting of N, O and S as heteroatoms, which ring is optionally substituted by phenyl-C1-6 alkyl, C1-6 alkoxy substituted phenyl-C1-6 alkyl, C1-6 alkyl, amino, cyano, hydroxy, carbamoyl, carboxy, C1-6 alkylamino, C1-6 alkoxycarbonyl, di(C1-6 alkyl)amino, benzylamino, C1-6 alkylsulfonyl, piperidino C1-6 alkyl carbonyl, or optionally fused by benzene;
• or
• —NR34R35,
• wherein R34 is hydrogen or C1-6 alkyl and
• R35 is hydrogen, a 5 to 8 membered saturated ring having 0 to 3 heteroatoms selected from the group consisting of N, O and S as heteroatoms, or —(CH2)m—NR351R352 (m represents any of integers from 1 to 6)
• wherein R351 represents hydrogen, C1-6 alkyl,
• R352 represents hydrogen, C1-6 alkyl, C1-6 alkanoyl, C1-6 alkylsubstituted phenyl, benzoyl, C1-6 alkanoyl, phenylaminocarbonyl, phenylsulfonyl, or
• R34 and R35 may form, together with the adjacent N atom, a 5 to 8 membered saturated heterocyclic ring, and said ring may optionally contain NH, S or O atom other than the adjacent N atom and optionally substituted by carbamoyl, amino, or C1-6 alkyl;
• R4 and R5 form,
• —R40—CO—NH—,
• —R40—SO2—NH—,
• —R40—C(═S)—NH—
• —R40—CH2—NH—,
• wherein said —R40— represents —CHR401—O—, —CH2—NR401—, —CO—NR401—, —CH2—CHR401—, —CH═CR401—, (in which R401 is C1-6 alkanoyl, C1-6 alkyl, phenyl, C1-6 alkylsulfonyl, C3-8 cycloalkylaminocarbonyl, hydrogen, halogen, nitro, amino, cyano, benzoylamino, phenylsulfonyl, carbamoyl, hydroxycarbonyl, C1-6 alkoxycarbonyl, C1-12 alkylaminocarbonyl, halogen substituted C1-6 alkylaminocarbonyl, C1-6 alkanoylamino, C1-6 alkylamino, di(C1-6 alkyl)aminocarbonyl, di(C1-6 alkyl)aminoC1-6 alkylaminocarbonyl, hydroindenylaminocarbonyl, diphenylmethylaminocarbonyl, pyrrolidinocarbonyl, C1-6 alkoxy C1-6 alkyl amino carbonyl, morpholinocarbonyl, piperazinocarbonyl, phenylC1-6alkylaminocarbonyl, hydroxycarbonylC1-6alkylaminocarbonyl, C3-8 cycloalkylaminocarbonyl, C3-8 cycloalkylC1-6alkylaminocarbonyl, hydroxyC1-6alkylaminocarbonyl, carboxyethylaminocarbonyl, C1-6alkylsulfonylaminocarbonyl)
• —CR41═N—NH— (R41 is hydrogen, amino, or C1-6alkanoylamino), or
• —CR42═N—C═N— (R42 is hydrogen or amino);
• and salts thereof.