Estrogen, in binding to bone-associated receptors, acts like a key that sets and activates a security system, the security system that protects against osteoporosis. But for some individuals, the binding of natural estrogen to breast cells carries the risk of unlocking the door to cancer. The observation that was critical in developing tamoxifen was that the receptors in different organ systems were slightly different proteins. Then inspiration had to go to work to devise a range of estrogen-like chemicals, and see which ones fit which locks the best. About a million infants and children a year die from this ravaging disease, caused by a parasite that literally consumes their red blood cells from the inside out.
Adults go on to lives of recurrent episodes of fever and debility.
Worse yet, the parasites are becoming resistant to drugs of the quinine type, which have long been mainstays of malaria treatment. American scientists looked for this familiar herb in parks around Washington, D.C., repeated the findings of their Chinese colleagues, and added to the knowledge about artemisinin by determining its chemical structure and preparing related molecules. Malaria parasites which are resistant to quinine are still susceptible to artemisinin, and better yet, artemisinin can treat the most dangerous form of malaria, when the parasite enters the brain. Devising that approach, and modifying artemisinin to be longer-acting, tested chemists' skill and inspiration. Tamoxifen is patterned on natural estrogen, but with some synthetic modification.