Abstract: The present invention is related to the use of novel agents effective for differential killing of abnormal cells such as cancer cells without damaging or being toxic to normal cells. Further these agents may be used for treating a host of ailments including various types of cancers, skin diseases, prevention and reversal of ageing process, prevention of inflammatory reactions, cure of bacterial infections, cure of fungal infections, etc. The agents are prepared by air oxidation of natural oils optionally in the presence of a catalyst wherein the isolated agents have Iodine value 40-60% of the starting oil, Saponification value 20-60 higher than that of the starting oil, Peroxide value 2-3 times that of the starting oil. These agents on saponification and acidification yield free fatty acids and ether linked fatty acid dimmer wherein the dimmer also acts as an active.