The present invention provides fused
heterocyclic derivatives represented by the following general formula (I) or pharmaceutically acceptable salts thereof, or prodrugs thereof, which exhibit an inhibitory activity in human SGLT and are useful as agents for the prevention or treatment of a
disease associated with hyperglycemia such as diabetes, postprandial hyperglycemia,
impaired glucose tolerance, diabetic complications or
obesity, in the formula R1 to R4 represent H, OH, an amino group, etc.; R5 and R6 represent H, OH, a
halogen atom, an option ally substituted
alkyl group, etc.; Q represents alkylene, alkenylene, etc.; ring A represents an
aryl group or a heteroaryl group; the following ring (R1) represents a group represented by the following ring (R2); G represents a group represented by the following general formula (G-1) or (G-2) (E1 represents H, F or OH; and E represents H, F, a
methyl group, etc.), and pharmaceutical compositions comprising the same, and pharmaceutical uses thereof.