The synthesis and biological evaluation of a series of 3-substituted 5-carboxamido derivatives of amsacrine (m-AMSA) are described. This series was developed as the result of previous quantitative structure-activity relationship (QSAR) studies of the antitumor activity of 9-anilinoacridine derivatives. In agreement with these studies, this class of compounds, possessing a variety of small nonpolar groups at the 3-position, together with very hydrophilic carboxamido groups at the 5-position, have high in vivo activity against animal leukemia models.