Improved antitumor effects of 3'-deamino-3'-morpholino derivatives of pirarubicin

The preparation and antitumor effects of 3'-deamino-3'-morpholino derivatives of pirarubicin are described. Di-N-alkylation of pirarubicin with bis(2-iodoethyl)ether gave 3'-morpholino-pirarubicin, which was converted into its 13-tosylhydrazone, 13-deoxy derivative and 13-(S)- and 13-(R)-dihydro derivatives. Intraperitoneal administration to murine tumors indicated that the effective dose ranges of the compounds having sp3 carbon at C-13 position were broader than those of the compounds having sp2 carbon. By oral administration, 13-(S)-dihydro isomer was more effective than 13-(R)-dihydro isomer.