title: Photocyclization of diethylstilbestrol. Isolation of a stable, self-trapping dihydrophenanthrene intermediate.
mesh_terms: D003500:Cyclization; D004054:Diethylstilbestrol / Q000528:radiation effects*; D004355:Drug Stability; D006900:Hydroxylation; D007536:Isomerism; D008027:Light; D010616:Phenanthrenes / Q000302:isolation & purification*; D010777:Photochemistry
chemical_list: D010616:Phenanthrenes; D004054:Diethylstilbestrol