PHOTOCHEMISTRY OF THE THIO-ANALOGUE OF THE DNA (6-4) PHOTOPRODUCT DEWAR VALENCE ISOMER : STRUCTURE OF A NEW PHOTOPRODUCT

Abstract Short wavelength (254 nm) irradiation of the thio-analogue 7 of the Dewar valence isomer of the DNA (6-4) pyrimidine-pyrimidinone photoproduct led to the formation of a “tetramer” which has been given structure 10 .