69075-29-2Relevant academic research and scientific papers
Large-scale synthesis of 5′-O-pixyl protected 2′- deoxynucleosides useful for oligonucleotide synthesis
Day, Robert T.,Williams, Dean,Soriano, Priscilla,Sanghvi, Yogesh S.
, p. 1135 - 1138 (2005)
Synthesis of 5′-O-pixylated 2′-deoxynucleosides 4 has been accomplished and the products are commercially available. Copyright Taylor & Francis, Inc.
Substituent and solvent effects of TMS triflate mediated C1′ epimerization of β-thymidine to α-thymidine
Sato, Yuichi,Tateno, Gohsuke,Seio, Kohji,Sekine, Mitsuo
, p. 87 - 93 (2007/10/03)
This paper deals with kinetic studies of TMSOTf-mediated C1′ epimerization of β-thymidine to α-thymidine. The effect of neighboring group participation by various 5′-hydroxy protecting groups, such as toluoyl, Et2CHC(O), Et2NC(O), and Et2NC(S), on the β→α conversion is described in detail. The time dependence of the ratio of the α and β anomers in the C1′ epimerization was estimated by 1H NMR. The α/β equilibrium constants K and the rate constants kα and kβ were calculated on the basis of the experimental data. As the result, it was concluded that, in acetonitrile, the α/β equilibrium constants K are thermodynamically affected by steric hindrance from the 5′-hydroxy protecting group. On the other hand, the rate constants kα and kβ are mainly influenced by the stability of the oxonium ion intermediate. In particular, formation of an intramolecularly cyclized iminium ion intermediate from the oxonium ion intermediate, due to the neighboring group participation by the diethylthiocarbamoyl group, tended to decrease the overall reaction rate. Finally, the α/β C1′ epimerization could be carried out with a high α anomer selectivity of 89% through the use of the Et2CHC(O) group. Thus, 5′-O-pixyl-α-thymidine could be synthesized from β-thymidine as a key intermediate for the synthesis of α-DNA in a considerably improved overall yield of 40%.
The pixyl (Px) group: A novel photocleavable protecting group for primary alcohols
Misetic, Ana,Boyd, Mary K.
, p. 1653 - 1656 (2007/10/03)
The 9-phenylxanthyl (pixyl or Px) moiety has been investigated as a potential photocleavable protecting group for primary alcohols. Alcohols 2a- e were protected in good yield by treatment with 9-chloro-9-phenylxanthene in dry pyridine at room temperature. Irradiation of the alcohol derivatives in neutral aqueous acetonitrile regenerates 2a-e and the 9-phenylxanthyl alcohol.
Modified oligodeoxyribonucleoditides
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, (2008/06/13)
Compounds for the treatment or prophylaxis of a viral infection in a mammal, which may be human, are provided. The compounds are oligodeoxyribonucleic acid derivatives, and a novel route to such compounds is also provided together with intermediates of mo
A General Approach to the Chemical Synthesis of Oligodeoxyribonucleotides
Balgobin, Neil,Josephson, Staffan,Chattopadhyaya, Jyoti B.
, p. 201 - 212 (2007/10/02)
A general procedure for the synthesis of oligodeoxynucleotides has been described using 9-phenylxanthen-9-yl as a 5'-protecting group.The building blocks 9 and 11, all sixteen of them in each category (Tables 2 and 3), have been unambiguously synthesized
THE 2-PHENYLSULFONYLETHYLCARBONYL (PSEC) GROUP FOR THE PROTECTION OF THE HYDROXYL FUNCTION
Balgobin, Neil,Josephson, Staffan,Chattopadhyaya, Jyoti B.
, p. 3667 - 3670 (2007/10/02)
The PSEC group may be used to protect the hydroxyl function in conjunction with a variety of acid and base labile protecting groups; the PSEC group may be removed by treatment of triethylamine (15 equiv.) in dry pyridine solution within 20 h at 20 deg C while other base labile protecting groups remained intact.
