This is the molecule of thymine. The formula for thymine is C₁₀H₁₄N₂O₅. Its molecular weight is 242.23 amu. The melting point of thymine is 186-7'C, its boiling point is 200-1'C, and its density is .915220. Thymine is the base of all nucleotides. Nucleotides are macromolecules that control the development of organisms and the production of other substances essential to life.