How virus-infected patients are treated has become more of a serious issue accompanying an increase in compromised hosts such as cancer patients, organ transplant patients, and AIDS patients. Further, the development of an effective anti-virus compound against a virus showing resistance to existing drugs has been strongly demanded. The invention provides a novel anti-DNA virus agent and a method of using the same. Further, the invention provides an anti-DNA virus agent effective also in a drug-resistant virus and a method of using the same.
