Differentiation between isomeric phenylglycidyl ether adducts of 2'-deoxyguanosine and 2'-deoxyguanosine-5'-monophosphate using liquid chromatography/electrospray tandem mass spectrometry.

The reaction between phenylglycidyl ether and 2'-deoxyguanosine or 2'-deoxyguanosine-5'-monophosphate yields a variety of different nucleoside and nucleotide adducts. The corresponding mixtures were analyzed by liquid chromatography/electrospray tandem mass spectrometry and the product ion spectra of the different isomers are discussed using the correct cone voltage and collision energy. The latter were selected by looking at the energy-resolved spectra. From these data the formation of N7 and N2 isomers was proposed. However, detailed NMR analysis of the latter proved this isomer to be the N(1)-alkylated adduct. The reaction between phenylglycidyl ether and 2'-deoxyguanosine or 2'-deoxyguanosine-5'-monophosphate yields a variety of different nucleoside and nucleotide adducts. The corresponding mixtures were analyzed by liquid chromatography/electrospray tandem mass spectrometry and the product ion spectra of the different isomers are discussed using the correct cone voltage and collision energy. The latter were selected by looking at the energy-resolved spectra. From these data the formation of N7 and N2 isomers was proposed. However, detailed NMR analysis of the latter proved this isomer to be the N(1)-alkylated adduct. 2'-Deoxyguanosine-5'-monophosphate was alkylated by phenylglycidyl ether at the 5'-phosphate position. If the nucleotide base moiety was alkylated, the corresponding tandem mass spectrometric data strongly suggested alkylation of N7. In the case of bis-PGE-dGMP adduct, evidence was found for simultaneous 5'-phosphate and N7-alkylation.2'-Deoxyguanosine-5'-monophosphate was alkylated by phenylglycidyl ether at the 5'-phosphate position. If the nucleotide base moiety was alkylated, the corresponding tandem mass spectrometric data strongly suggested alkylation of N7. In the case of bis-PGE-dGMP adduct, evidence was found for simultaneous 5'-phosphate and N7-alkylation.