Synthesis and biological evaluation of novel steroid-linked nitrogen mustards

Two novel steroid-linked nitrogen mustard conjugates 1a and 1b were synthesized by using estrogenic acid 4 coupled with aniline mustard 8 and phenol mustard 13 in an esterification or amidation procedure. Preliminary cytotoxic screening on cancer cell lines in vitro showed that, the steroid-ester linked nitrogen mustard conjugate 1a exhibited obvious increasing of activities.