Figure 3: HPLC chromatogram of irradiated and nonirradiated diethyl 4,4’ – methylenebis (N -phenylcarbamate). Detection was carried out by UV (248 nm) and ECD (900 mY). The structure of peaks (a)-{i} are determined as indicated in the footnote; (a) is a starting compound. They are produced predominantly by the cleavage at C-C linkage.