Photo-alteration of hydantoins against UV light and its relevance to prebiotic chemistry

► 5-Substituted hydantoins are the photochemical precursors of hydantoin. ► UV-irradiated 5-substituted hydantoins are the hydrolytic precursors of Gly and Ala. ► Stability of hydantoins against UV radiation is: Hyd ≫ M-Hyd > E-Hyd ≧ DM-Hyd ≧ EM-Hyd.