Potential antineoplastics. 4th communication: N-mustard derivatives of estrone).

The nitrogen mustards 5 and 9 are synthesized as potential mammatropic antineoplastic agents from estrone via 2--4 or 6--8, respectively. 5 and 9 show a binding affinity to the cytoplasmic estrogen receptor of the rat uterus of 1--10% compared to that of estrone. Both mustard compounds are irreversibly bound to the estrogen receptor.