Derivatives of 2-methoxy-pyridin-4-yl

A compound of formula (I): ** ** in Formula A represents ** ** Formula in which the asterisks indicate the bond that is linked to the pyridine group of Formula (I); R1 represents cyclopentyl; R2 represents methyl and R4 represents ethyl or chloro; or R2 represents methoxy, and R4 is chlorine; R3 represents OCH 2 COOH, -OCH2CH2CH2COOH, -OCH2CONHCH2CH2OH, -OCH2CH2CH2CONHCH2CH2OH, - OCH2- (CH2) n-NH- (CH2) m-COOH, -OCH2- (CH2) nN (CH3) - (CH2) m-COOH, 2 - [(azetidin-3-carboxylic acid) -1-yl] -ethoxy, 2 - [(pyrrolidine-3-carboxylic acid) -1-yl] -ethoxy, 3 - [(azetidin-3-carboxylic acid) -1 -yl] -propoxy, 3 - [(pyrrolidine-3- carboxylic acid) -1-yl] -propoxy, -OCH2CH (OH) -CH2NH-CH2COOH, -OCH2CH (OH) -CH2NH-CH2CH2COOH, - OCH2CH (OH) -CH2N (CH3) 2 COOH, -OCH 2 CH (OH) -CH 2 N (CH 3) -CH2CH2COOH, 3 - [(azetidine-3- carboxylic acid) -1-yl] -2-hydroxy-propoxy, 2-hydroxy-3- [(pyrrolidine-3-carboxylic acid) -1-yl] -propoxy, -OCH2- (CH2) n-NHCH2CH2OH, -OCH2- (CH2) n-NH-CH (CH2OH) 2, -OCH2- (CH2) n -NH-CH2CH (OH) CH2OH, -OCH2CH (OH) -CH2NH CH2CH2OH, -OCH2CH (OH) -CH2NH-CH (CH2OH) 2, -OCH2- (CH2) k-NH-CO-CH2OH, -OCH2- (CH2) n-NH-COCH2COOH, -OCH2- (CH2) n-NH-CO-CH2CH2COOH, -OCH2CH (OH) -CH2NH-CO- (CH2) n COOH, -OCH 2 (CH 2) n N (CH3) -CO-CH2OH, -OCH2- (CH2) nN (CH3) -CO-CH 2 COOH or -OCH 2 (CH2) nN (CH3) -CO-CH2CH2COOH; n represents, independently, 1 or 2; m represents, independently, 1, 2 or 3; k represents 1 or 2; or a salt thereof.