sentences:  A number of structurally modified analogs of mitoxantrone were synthesized and structure-activity relationship studies made.BBR 2778 was originally synthesized by University of Vermont researchers Miles P. Hacker and Paul A. Krapcho and initially characterized in vitro for tumor cell cytotoxicity and mechanism of action by studies at the Boehringer Mannheim Italia Research Center, Monza, and University of Vermont, Burlington.Other studies have been completed at the University of Texas M. D. Anderson Cancer Center, Houston, the Istituto Nazionale Tumori, Milan, and the University of Padua.