Comparison of Synthetic Psoralen Derivatives and 8‐MOP in the Inhibition of Lymphocyte Proliferationa

Psoralens are a family of furocoumarins that naturally occur in nature in small amounts in a variety of common vegetables, including figs and limes, and in larger quantities in plants originally identified in the Nile valley and in India.' These molecules have the remarkable quality of being activated by ultraviolet A (UVA) from a biologically inert form to one capable of forming covalent bonds with the pyrimidine bases of DNA.