Secretin
Secretin was the first hormone to be identified. In 1902, William Bayliss and Ernest Starling were studying how the nervous system controls the process of digestion. It was known that the pancreas secreted digestive juices in response to the passage of food (chyme) through the pyloric sphincter into the duodenum. They discovered (by cutting all the nerves to the pancreas in their experimental animals) that this process was not, in fact, governed by the nervous system. They determined that a substance secreted by the intestinal lining stimulates the pancreas after being transported via the bloodstream. They named this intestinal secretion "secretin". Secretin was the first such "chemical messenger" identified. This type of substance is now called a hormone, a term coined by Bayliss in 1905.
Gordon Alles
Gordon A. Alles (November 26, 1901 – January 21, 1963), was an American chemist and pharmacologist who did much research on the isolation and properties of insulin for the treatment of diabetics. He is also credited with discovering and publishing the psychological effects of amphetamine, and for methylenedioxyamphetamine (MDA). He is the first person to have prepared amphetamine sulfate, although not the amphetamine molecule. Alles first reported the physiological properties amphetamine as a synthetic analog of ephedrine, and therefore received credit for this discovery. He enjoyed large royalties from Smith, Kline & French (SKF) because he sold his patent rights for amphetamine to the company and it enjoyed large sales. Several popular products sold by SKF contained amphetamine including Benzedrine pills and inhalers, Dexedrine pills, and Dexamyl tablets. Counterfeit drugs appeared, trying to violate Alles' 'weak' patent, e.g., "Profetamine".