The present invention relates to a novel pyridine derivative or a pharmacologically acceptable ester thereof, or a pharmacologically acceptable salt of the derivative or ester, which has an excellent hypoglycemic effect or treats and/or prevents the onset of a disorder of carbohydrate or lipid metabolism or a disease mediated by peroxisome proliferator-activated receptor (PPAR) γ. A compound represented by the general formula (I): [wherein R represents a pyridyl group substituted with 1 to 3 group(s) independently selected from Substituent Group A, and Substituent Group A represents a halogen atom, a C1-C6 alkyl group and a C1-C6 alkoxy group] or a pharmacologically acceptable ester thereof, or a pharmacologically acceptable salt of the compound or ester.