Figure I. A solution of lc (0.2 mM) in 5 0 m~ phosphate buffer at pH= 7.2 was exposed to irridiation (364.5 nm) from a Hg-Xe lamp a) UV-spectra recorded during photolysis. The lowest trace at 230 and 300 nm and the highest trace at 260 nm correspond to the starting material Ic. b) Aliquots (20 mL) of the irradiated sample were analyzed by HPLC. Compound lc had a retention time of 8.9 min. The peak at 4.7 min corresponds the photolysis by- ...