Synthesis and biological evaluation of novel daunorubicin-estrogen conjugates

The synthesis of two novel daunorubicin-estro-en conjugates with a steroida l and a non-steroidal ligand was undertaken in an attempt to target the cyt otoxicity of anthracycline to estrogen-receptor positive cells. These conju gates (3 and 4), in contrast to their corresponding ligands, displayed weak binding affinities of 0.079 and 0.851 for the estrogen receptor. Conjugate 3 was consistently more cytotoxic than 4, which however showed some select ivity to estrogen receptor positive cell lines. (C) 2001 Elsevier Science I nc. All rights reserved.