title: Determination of N9/N7-isomer ratio of alkyl (guaninyl)acetates by electrospray ionization tandem mass spectrometry.
abstract: N9- and N7-substituted (guaninyl)acetic esters were studied by electrospray ionization tandem mass spectrometry (ESI-MS/MS) in order to determine their ratio in alkylation reactions. The loss of ammonia is significantly different for the N9- and N7-alkylated guanine regioisomer pairs. More importantly, the abundance of the [MH-17]+ ion is in linear correlation with the N9-isomer content. Therefore, the ratio of regioisomers can be determined in a mixture containing these compounds.
authors.affiliation: Department of Medicinal Chemistry, University of Szeged, Dóm tér 8, H-6720 Szeged, Hungary.
authors.forename: Györgyi
authors.initials: G
authors.lastname: Ferenc
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Kele
authors.forename: Lajos
authors.initials: L
authors.lastname: Kovács
mesh_terms: D000085:Acetates / Q000737:chemistry*; D006147:Guanine / Q000737:chemistry*; D009584:Nitrogen / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013237:Stereoisomerism
chemical_list: D000085:Acetates; D006147:Guanine; D009584:Nitrogen