Learn about chemist Percy Julian's work to synthesize cortisone. Julian's work made cortisone—a steroid used to treat rheumatoid arthritis—more easily accessible to millions of patients. Julian knew from earlier studies that plants and animals produced steroids with the same carbon-ring structure, so he isolated large quantities of molecules that closely resembled human cortisone from a cheap and abundant plant source—soybeans. Learn more about this topic, from the NOVA program Percy Julian: Forgotten Genius.