MONOCYCLIC PYRIDINE DERIVATIVE

The present invention discloses a compound represented by the following formula (IA) or a pharmaceutically acceptable salt thereof: wherein n represents 0 to 2; A represents an arylene group or a heteroarylene group; G represents a single bond, an oxygen atom or -CH 2 -; E represents a nitrogen-containing non-aromatic heterocycle; R 1 represents an alkoxy group, an alkoxy alkoxy group or the like; R 2 represents a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group, a hydroxy alkyl group, a nitrogen-containing non-aromatic heterocyclic group or the like; R 3 represents a hydrogen atom, an alkyl group, an alkoxy group or the like; and R 4 represents a C 1-6 alkyl group, with the proviso that when E represents an azetidine ring and R 2 or R 3 is present on a nitrogen atom on the azetidine ring, the R 2 or R 3 does not represent a hydrogen atom.