Remarkable stabilization of antiparallel DNA triplexes by strong stacking effects of consecutively modified nucleobases containing thiocarbonyl groups
摘要:
The consecutive arrangement of 2'-deoxy-6-thioguanosines (s(6)Gs) and 4-thiothymidines (s(4)Ts) in antiparallel triplex-forming oligonucleotides (TFOs) considerably stabilized the resulting antiparallel triplexes with high base recognition ability by the strong stacking effects of thiocarbonyl groups. This result was remarkable because chemical modifications of the sugar moieties and nucleobases of antiparallel TFOs generally destabilize triplex structures. Moreover, in comparison with unmodified TFOs, it was found that TFOs containing s(6)Gs and s(4)Ts could selectively bind to the complementary DNA duplex but not to mismatched DNA duplexes or single-stranded RNA. (c) 2012 Elsevier Ltd. All rights reserved.
The synthesis of a menthol derivative of 2-aminopurine as a fluorescent DNA lesion
作者:Wouter F.J. Hogendorf、Carlo P. Verhagen、Erik Malta、Nora Goosen、Herman S. Overkleeft、Dmitri V. Filippov、Gijsbert A. Van der Marel
DOI:10.1016/j.tet.2009.10.023
日期:2009.12
An efficient synthetic route to the phosphoramidite of a menthol functionalized guanosine analog is presented. Two procedures were executed for the key introduction of the 6′-allyl menthyl moiety. Stille vinylation on 6-O-tosylguanosine followed by cross-metathesis using an excess of allyl menthyl ether proved to be less efficient than a Stillecoupling on the same tosylate using an advanced menthyl-allyl
Previously, we reported 2-N-carbamoylguanine (cmG) as a guanine analog. We further studied the synthetic protocol and hybridizationproperties of oligodeoxynucleotides (ODNs) incorporating cmG. These ODNs were synthesized using the phosphoramidite of cmG without protection of the 6-O position. However, the isolated products were contaminated with deacylated products having guanine in place of cmG.
BODIPY-modified 2′-deoxyguanosine as a novel tool to detect DNA damages
作者:Takeji Takamura-Enya、Ryoko Ishii
DOI:10.1016/j.bmcl.2011.05.084
日期:2011.7
BODIPY-modified 2'-deoxyguanosine was synthesized for use as a detection reagent for genotoxic compounds. BODIPY-FL is a well known fluorescence reagent whose fluorescent light emission diminishes near a guanine base by a photo-induced electron transfer process. We attached BODIPY-FI to the 5' position of the deoxyribose moiety of 2'-deoxyguanosine. Although this compound has low fluorescence activity, when depurination by the action of alkylating reagents and dG oxidation by singlet oxygen occurred, the emission of strong fluorescence was observed. BODIPY-dG was found, therefore, to be a very useful tool for selectively detecting DNA damaging activity particularly in natural environmental extracts. (C) 2011 Elsevier Ltd. All rights reserved.
Remarkable stabilization of antiparallel DNA triplexes by strong stacking effects of consecutively modified nucleobases containing thiocarbonyl groups
The consecutive arrangement of 2'-deoxy-6-thioguanosines (s(6)Gs) and 4-thiothymidines (s(4)Ts) in antiparallel triplex-forming oligonucleotides (TFOs) considerably stabilized the resulting antiparallel triplexes with high base recognition ability by the strong stacking effects of thiocarbonyl groups. This result was remarkable because chemical modifications of the sugar moieties and nucleobases of antiparallel TFOs generally destabilize triplex structures. Moreover, in comparison with unmodified TFOs, it was found that TFOs containing s(6)Gs and s(4)Ts could selectively bind to the complementary DNA duplex but not to mismatched DNA duplexes or single-stranded RNA. (c) 2012 Elsevier Ltd. All rights reserved.
<i>O</i>
<sup>6</sup>
-Alkylguanine DNA Alkyltransferase Repair Activity Towards Intrastrand Cross-Linked DNA is Influenced by the Internucleotide Linkage
作者:Derek K. O'Flaherty、Christopher J. Wilds
DOI:10.1002/asia.201501253
日期:2016.2
Oligonucleotides containing an alkylene intrastrand cross‐link (IaCL) between the O6‐atoms of two consecutive 2′‐deoxyguanosines (dG) were prepared by solid‐phase synthesis. UV thermal denaturation studies of duplexes containing butylene and heptylene IaCL revealed a 20 °C reduction in stability compared to the unmodified duplexes. Circular dichroism profiles of these IaCL DNA duplexes exhibited signatures