Photoreaction of 8‐methoxypsoralen With Thymidine

Abstract—The photoreaction of 8‐methoxypsoralen (8‐MOP) with thymidine in solid film state yielded two 4′, 5′‐monoadducts (a pair of diastereomers) and three 3,4‐monoadducts. The stereochemistry of two 4′, 5′‐monoadducts was found to becis‐synandtrans‐synand one 3,4‐monoadduct wascis‐anti.In addition to these monoadducts, 3,4‐, 4′, 5′‐biadducts were also formed during the reaction, but the isolation of each isomer of these adducts was not successful; however, the formation of these biadducts was confirmed by UV, IR, TLC and photosplitting experiments.