title: Reactions of ethyleneimine with guanosine and deoxyguanosine.
abstract: Ethyleneimine was reacted with guanosine in aqueous medium and the products were purified by Sephadex G-10 and high-performance liquid chromatography (HPLC). Two products were identified by UV-spectroscopy: imidazole-ring opened 7-alkylguanosine and 1-alkylguanosine, accounting for 80% and 14% of all adduct radioactivity, respectively. When the incubation with ethyleneimine and guanosine or deoxyguanosine was carried out at pH 6.0 for 1 h intact 7-alkylation products were detected. The half-life of imidazole ring opening of 7-alkylguanosine was 11, 5 and 2.8 min at pH-values 7.0, 7.7 and 8.0, respectively, as measured fluorometrically at 25 degrees C. The respective half-life of alkylated deoxyguanosine was 21 min at pH 7.7. The half-life of depurination of alkylated deoxyguanosine was 42 min at pH 6.0 and 25 degrees C.
mesh_terms: D001388:Aziridines; D001389:Azirines; D055598:Chemical Phenomena; D002621:Chemistry; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D003849:Deoxyguanosine; D006151:Guanosine; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet
chemical_list: D001388:Aziridines; D001389:Azirines; D006151:Guanosine; C033132:aziridine; D003849:Deoxyguanosine