Electric double-layer capacitor

An activated carbon comprising a carbonized and activated compound represented by the formula (1): (wherein, R represents a hydrocarbon group having 1 to 12 carbon atoms, said hydrocarbon group may be optionally substituted with hydroxyl group, alkyl group, alkoxy group, aryl group, aryloxy group, sulfonyl group, halogen atoms, nitro group, thioalkyl group, cyano group, carboxyl group, amino group or amide group, R′ represents hydrogen atom or methyl group, and n represents an integer of 4, 6, or 8).