Derivatives of plumbagin can be selectively cytotoxic to breast cancer cells. Derivative ‘A’ (Acetyl Plumbagin) has emerged as a lead molecule for testing against estrogen positive breast cancer and has shown low hepatotoxicity as well as overall lower toxicity in nude mice model. The toxicity of derivative ‘A’ was determined to be even lower than vehicle control (ALT and AST markers). The possible mechanism of action identified based on the microarray experiments and pathway mapping shows that derivative ‘A’ could be acting by altering the cholesterol-related mechanisms. The low toxicity profile of derivative ‘A’ highlights its possible role'as future anti-cancer drug and/or as an adjuvant drug to reduce the toxicity of highly toxic chemotherapeutic'drugs.