Nemorubicin (Methoxymorpholinyl doxorubicin) is a Doxorubicin derivative with potent antitumor activity. Nemorubicin is highly cytotoxic to a variety of tumor cell lines presenting a multidrug-resistant phenotype. Nemorubicin not only intercalate into the duplex DNA, but also result in significant ligands for G-quadruplex DNA segments, stabilizing their structure. Nemorubicin requirs an intact nucleotide excision repair (NER) system to exert its activity.