Structural Modification for Antitumor Nitrogenous Steroids

Natural steroids have been showing notable cytotoxic activities, which are quite interesting lead compounds for the development of anticancer drug including estramustine and prednimustine. Considering that these semi-synthetic molecules are nitrogen mustard functionalized steroidal derivatives, the present review is focused on the methodologies of introducing nitrogen atom or nitrogen-containing heterocycles on A similar to D rings or side chains of steroids, and analysis of the structure-activity relationship (SAR) for these man-made cytotoxic steroids.