Breast cancer is reported to be one of the commonest cancers and the most common cause of cancer death among women worldwide, and especially young women in the developing world. Anti-cancer agents, which combine two biologically active compounds in one such as hybrid steroids attain both hormone and cytotoxic effects on cancer cells. The aim of the present study is to synthesize and evaluate new potential chemotherapeutic anti-breast cancer agents. Several pyridazino-, pyrimido-, quinazolo-, oxirano- and thiazolo-steroid derivatives were synthesized. The most structurally promising, compounds...