This image illustrates the chemical structures of the five main nucleobases found in DNA and RNA. The pyrimidines, thymine (DNA), uracil (RNA), and cytosine are shown on top while the purines, adenine ...

Adenine was first discovered in 1885 by the German physiologist Albrecht Kossel. He isolated adenine from the pancreas of oxen and named it "adenine" derived from the Greek word "aden," meaning gland.