The present invention provides a compound having high antitumor activity, which is useful for therapeutic and preventive agents effective for proliferative diseases such as cancer; a production method thereof; an intermediate compound useful for such production; and a pharmaceutical composition comprising such a compound. The present invention provides a compound represented by the formula (1):
wherein X represents an aryl group or heteroaryl group which may be substituted, Cy represents a 4- to 7-membered monocyclic heterocyclic ring or a 8- to 10-membered condensed heterocyclic ring which may be substituted, and Z represents O, S, or NRa; or a prodrug thereof; or a pharmaceutically acceptable salt thereof; and a pharmaceutical and a pharmaceutical composition which comprise the compound.