text: A partial extraction procedure was developed in 1935 which involved reacting the compound with benzoyl chloride to allow it to be separated from the water-soluble components. The compound was first isolated and purified to crystals by Osamu Shimomura. The structure of the compound was confirmed some years later. Feeding experiments suggest that the compound is synthesized in the animal from three amino-acids: tryptophan, isoleucine, and arginine.