- Self-Assembly of Functionalized Lipophilic Guanosines into Cation-Free Stacked Guanine-Quartets
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The hierarchical self-assembly of various lipophilic guanosines exposing either a phenyl or a ferrocenyl group in the C(8) position was investigated. In a solution, all the derivatives were found to self-assemble primarily into isolated guanine (G)-quartets. In spite of the apparent similar bulkiness of the two substituents, most of the derivatives form disordered structures in the solid state, whereas a specific 8-phenyl derivative self-assembles into an unprecedented, cation-free stacked G-quartet architecture.
- Campitiello, Marilena,Cremonini, Alessio,Squillaci, Marco A.,Pieraccini, Silvia,Ciesielski, Artur,Samorì, Paolo,Masiero, Stefano
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p. 9970 - 9978
(2021/07/31)
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- Pd(0)/Cu(I)-mediated direct arylation of 2′-deoxyadenosines: Mechanistic role of Cu(I) and reactivity comparisons with related purine nucleosides
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(Chemical Equation Presented) Pd/Cu-mediated direct arylation of 2′-deoxyadenosine with various aryl iodides provides 8-arylated 2′-deoxyadenosine derivatives in good yields. Following significant reaction optimization, it has been determined that a subst
- Storr, Thomas E.,Baumann, Christoph G.,Thatcher, Robert J.,De Ornellas, Sara,Whitwood, Adrian C.,Fairlamb, Ian J. S.
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supporting information; experimental part
p. 5810 - 5821
(2009/12/26)
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- A facile two-step synthesis of 8-arylated guanosine mono- and triphosphates (8-aryl GXPs)
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We report a simple and high-yielding two-step procedure for the preparation of 8-arylated guanosine mono- and triphosphates (8-aryl GXPs). The key step of our synthesis is the Suzuki-Miyaura coupling of unprotected 8-bromo GMP and 8-bromo GTP with various
- Collier, Alice,Wagner, Gerd
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p. 4526 - 4532
(2008/09/19)
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- Suzuki-Miyaura cross-coupling of unprotected halopurine nucleosides in water - Influence of catalyst and cosolvent
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Reaction conditions for the Suzuki-Miyaura cross-coupling of unprotected halopurine nucleosides with arylboronic acids in aqueous media were investigated. A series of arylated purine nucleosides was prepared in water without an organic cosolvent, using either Pd(PPh3)4 or Pd(OAc)2/TPPTS as the catalyst. Copyright Taylor & Francis Group, LLC.
- Collier, Alice,Wagner, Gerd K.
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p. 3713 - 3721
(2007/10/03)
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- Efficient one-step Suzuki arylation of unprotected halonucleosides, using water-soluble palladium catalysts
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Modification of nucleosides to give pharmaceutically active compounds, mutagenesis models, and oligonucleotide structural probes continues to be of great interest. The aqueous-phase modification of unprotected halonucleosides is reported herein. Using a catalyst derived from tris(3-sulfonatophenyl)phosphine (TPPTS) and palladium acetate, 8-bromo-2′-deoxyguanosine (8-BrdG) is coupled with arylboronic acids to give 8-aryl-2′-deoxyguanosine adducts (8-ArdG) in excellent yield in a 2: 1 water: acetonitrile solvent mixture. The TPPTS ligand was found to be superior to water-soluble alkylphosphines for this coupling reaction. The coupling chemistry has been extended to 8-bromo-2′-deoxyadenosine (8-BrdA) and 5-iodo-2′-deoxyuridine (5-IdU), as well as the ribonucleosides 8-bromoguanosine and 8-bromoadenosine. Good to excellent yields of arylated adducts are obtained in all cases. With use of tri(4,6-dimethyl-3-sulfonatophenyl)phosphine (TXPTS), the Suzuki coupling of 8-BrdA and 5-IdU can be accomplished in less than 1 h at room temperature. This methodology represents an efficient and general method for halonucleoside arylation that does not require prior protection of the nucleoside.
- Western, Elizabeth C.,Daft, Jonathan R.,Johnson II, Edward M.,Gannett, Peter M.,Shaughnessy, Kevin H.
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p. 6767 - 6774
(2007/10/03)
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- Reactions of Benzenediazonium Ions with Guanine and Its Derivatives
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Guanine reacts with several benzenediazonium ions rapidly in aqueous solution at pH 10.5 to form 8-(arylazo)guanines in good yield.The reaction of guanine with 4-bromobenzenediazonium ion forms ε-guanine about 50-fold more rapidly than the reaction of adenine with this ion to yield 6-purine under these experimental conditions.Guanosine reacts much more slowly than guanine with the benzenediazonium ions in aqueous solution at pH 8.5 or 10.5 to give 8-arylguanosines.The structures of these products were established by their spectroscopic properties and by their quantitative conversion to 8-arylguanines. 5'-Guanylic acid also reacts quite slowly with the benzenediazonium ions in aqueous solution at pH 10.5.Only the compounds with strong electron-withdrawing groups yield N-2 triazenes at ambient temperature.No 8-aryl or 8-arylazo compounds are formed with 5'-guanylic acid at this temperature.However, 4-bromo- and 4-sulfobenzenediazonium ions react with 5'-guanylic acid at higher temperatures to yield the 8-aryl-5'-guanylic acids in low yield.The structures of these products were proven by hydrolysis to 8-arylguanines.The 8-arylguanosines and the 8-aryl-5'-guanylic acids are formed via free-radical phenylation reactions.The factors governing the reactivity of the adenines and the guanines are discussed.
- Hung, Ming-Hong,Stock, Leon M.
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p. 448 - 453
(2007/10/02)
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