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• 961-07-9 2'-Deoxyguanosine 
• 88847-89-6 7,8-dihydro-8-oxo-2'-deoxyguanosine 

Relevant academic research and scientific papers

Identification of the α and β anomers of 1-(2-deoxy-D-erythro- pentofuranosyl)-oxaluric acid at the site of riboflavin-mediated photooxidation of guanine in 2′-deoxyguanosine and thymidylyl-3′-5′- deoxyguanosine

Products of riboflavin-mediated photosensitization of 2′- deoxyguanosine (dG) and thymidylyl-(3′-5′)-2′-deoxyguanosine (TpdG) by 350-nm light in oxygen-saturated aqueous solution have been isolated and identified as 1-(2-deoxy-β-erythro-pentofuranosyl) oxaluric acid (β-dOx) and thymidylyl-(3′-5′)-1-(2-deoxy-β-D-erythro- pentofuranosyl) oxaluric acid (Tpβ-dOx), respectively. In aqueous solution the modified β-deoxyribonucleoside is slowly converted to the α-anomer, generating α-dOx and Tpα-dOx. These modified nucleosides and dinucleoside monophosphates have been isolated by HPLC and characterized by proton and carbon NMR spectroscopy, fast atom bombardment mass spectrometry, and enzymatic analyses. Both α-dOx and Tpα-dOx slowly convert back into the modified β-deoxyribonucleoside, indicating that the furanosidic anomers are in dynamic equilibrium. Relative to TpdG, the rate of hydrolysis of Tpβ-dOx and Tpα-dOx by spleen phosphodiesterase is greatly reduced. Hot piperidine (1.0 M, 90°C, 30 min) destroys Tpβ-dOx and Tpα-dOx. Riboflavin-mediated photosensitization of TpdG in D 2O instead of H2O has no detectable effect on the yield of Tpβ-dOx, suggesting that oxaluric acid is generated through a Type-I reaction mechanism, likely through the intermediary on initially generated 8-oxo-7,8-dihydro-2′-deoxyguanosine.

Formation of a diimino-imidazole nucleoside from 2′-deoxyguanosine by singlet oxygen generated by methylene blue photooxidation

Singlet oxygen (1O2) is capable of inducing genotoxic, carcinogenic and mutagenic effects. It has previously been reported that the reaction of 1O2 with 2′-deoxyguanosine, which is a major target of 1O2 among the DNA constituents, leads to formation of various oxidized products including 8-oxo-7,8-dihydro-2′-deoxyguanosine and spiroiminodihydantoin, amino-imidazolone and diamino-oxazolone nucleosides. In addition to these products, we report that a novel diimino-imidazole nucleoside, 2,5-diimino-4-[(2-deoxy-β-D-erythro-pentofuranosyl)amino]-2H,5H- imidazole (dD), is formed by reaction of 2′-deoxyguanosine with 1O2 generated by irradiation with visible light in the presence of methylene blue under aerobic conditions. Its identification is based on identical chromatographic and spectroscopic data with an authentic compound, which we recently isolated and characterised from the reaction mixture of 2′-deoxyguanosine with reagent HOCl and a myeloperoxidase-H2O2-Cl- system. The yield of dD was increased by D2O and decreased by azide. dD was not generated from 8-oxo-7,8-dihydro-2′-deoxyguanosine. These results indicate that dD is generated by 1O2 directly from 2′-deoxyguanosine, but not via 8-oxo-7,8-dihydro-2′-deoxyguanosine. dD may play a role in the genotoxicity of singlet oxygen in cells.

Photooxydation sensibilisee de la desoxy-2' guanosine par des phtalocyanines et naphtalocyanines. Determination de l'importance des mecanismes de type I et de type II

The photodynamic properties of sulfonated derivatives of phthalocyanine and naphthalocyanine were investigated using 2'-deoxyguanosine as a model compound for DNA.The major degradation photoproducts of this nucleoside were characterized and classified into two categories.The degradation involving the radical mechanism (type I) led to the formation of 2,2-diamino-5-oxazolone.The two main photooxidation products involving type II mechanism were characterized as the 4R* and 4S* diastereoisomers of 9-(2-β-D-deoxyerythropentofuranosyl)-4,8-dihydro-4-hydroxy-8-oxoguanine.In addition, 8-oxo-7,8-dihydro-2'-deoxyguanosine was shown to be generated (probably through type II mechanism).By identifying and quantifying these photoproducts, the ratio of type I/type II photoprocess was established for three (aluminum, gallium and zinc) disulfonated phthalocyanines and a tetrasulfonated aluminum naphthalocyanine.It was found that the type II mechanism is predominant.

Etude comparative de l'oxydation radicalaire de l'ADN et de ses nucleosides par les radicaux hydroxyles et les ions ferryles issus de la reaction de Fenton

A comparative study of the reaction of hydroxyl radicals and Fenton type oxidative species with DNA and 2'-deoxyribonucleosides was investigated.This study was based on the characterization of the diamagnetic products resulting from the chemical transformation of the transient radicals.Emphasis was placed on the radical oxidative reactions of the purine nucleosides.It is interesting to note that oxidative purine radicals can be reduced by reagents such as ascorbic acid or N,N,N',N'-tetramethyl-1,4-p-phenylenediamine.The observed differences in the nature of the decomposition products resulting from the Fenton reaction are not consistent with the nature of the oxidative species (hydroxyl radicals or ferryl ions) involved, but due to the presence of ferrous sulfate.