title: C4-cyclodimers of psoralen engaging the 4',5'-double bond.
mesh_terms: D055598:Chemical Phenomena; D002621:Chemistry; D004247:DNA; D011564:Furocoumarins / Q000528:radiation effects*; D010777:Photochemistry; D014466:Ultraviolet Rays
chemical_list: D011564:Furocoumarins; D004247:DNA