Patent ID: 7196080

Claim:
A pyridine derivative represented by the following general formula (I) or a pharmaceutically acceptable salt thereof: wherein each symbol has the following meaning: R 1 : O-a lower alkyl, R 2 : O-a lower alkyl or O-a lower alkylene-a hydrocarbon ring, R 3 and R 4 : the same or different from each other, H, or a lower alkyl, R 5 : an optionally substituted phenyl or an optionally substituted heterocycle selected from the group consisting of pyridine, thiazole, pyrazine, pyrimidine, benzofuran, piperidine, pyridazine, quinoline, 2,3-dihydro-1,4-benzodioxine, benzothiazole, benzoxazole and indole, wherein the substituent in the optionally substituted phenyl and the optionally substituted heterocycle is a group selected from the following G group: G group: groups represented by (i) —X-a C 1-6 alkylene-A, (ii) -a C 1-6 alkylene-A, or (iii) —B, wherein X is O, S, SO, SO 2 , NH, N(a C 1-6 alklyl), SO 2 NH, SO 2 N(a C 1-6 alkyl), NHSO 2 , N(a C 1-6 alkyl)SO 2 , CO, CO 2 , O—CO, CONH, CON(a C 1-6 alkyl), NHCO, N(a C 1-6 alkyl )CO or NHCONH, A is —CN, —OH, —CO 2 H, —CO 2 -a C 1-6 alkyl, —NO 2 , —SO 3 H, —NH 2 , —CONH 2 , —SO 2 NH 2 , a C 1-6 alkyl substituted with halogen(s), —NH-a C 1-6 alkylene-O-a C 1-6 alkyl, —N(a C 1-6 alkyl)-a C 1-6 alkylene-O-a C 1-6 alkyl, —N(—C 1-6 alkylene-O-a C 1-6 alkyl) 2 , -a hydrocarbon ring, -a heterocycle selected from the group consisting of morpholine, pyridine, pyridine-N-oxide, piperidine, piperazine, tetrazole, pyrrolidine and thiomorpholine, —X-a C 1-6 alkyl, —X-a C 1-6 alkyl substituted with halogen(s), —X-a hydrocarbon ring, —X-a heterocycle selected from the group consisting of morpholine, pyridine, pyridine-N-oxide, piperidine, piperazine, tetrazole, pyrrolidine and thiomorpholine, —X-a C 1-6 alkylene-CN, —X-a C 1-6 alkylene-OH, —X-a C 1-6 alkylene-CO 2 H, —X-a C 1-6 alkylene-CO 2 -a C 1-6 alkyl, —X-a C 1-6 alkylene-NO 2 , —X-a C 1-6 alkylene-SO 3 , —X-a C 1-6 alkylene-NH 2 , —X-a C 1-6 alkylene-CONH 2 , —X-a C 1-6 alkylene-SO 2 NH 2 , —X-a C 1-6 alkylene-a hydrocarbon ring or —X-a C 1-6 alkylene-a heterocycle selected from the group consisting of morpholine, pyridine, pyridine-N-oxide, piperidine, piperazine, tetrazole, pyrrolidine and thiomorpholine, B is -a C 1-6 alkyl, -a halogen, a C 1-6 alkyl substituted with halogen(s), or a group described in A, and the hydrocarbon ring and heterocycle in the above A and B may have from 1 to 5 substituents selected from the group consisting of a C 1-6 alkyl, a halogen, a C 1-6 alkyl substituted with halogen(s), CN, OH, O-a C 1-6 alkyl, NH 2 , —NH-a C 1-6 alkyl, —N(a C 1-6 alkyl) 2 , S-a C 1-6 alkyl, SO-a C 1-6 alkyl, SO 2 -a C 1-6 alkyl, SO 2 NH 2 , SO 2 NH-a C 1-6 alkyl, SO 2 N(a C 1-6 alkyl) 2 , NHSO 2 -a C 1-6 alkyl, CO 2 H, CO 2 -a C 1-6 alkyl, CONH 2 , CONH-a C 1-6 alkyl, CON(a C 1-6 alkyl) 2 and NHCO-a C 1-6 alkyl, and n: 0.