51600-12-5Relevant academic research and scientific papers
Direct One-Pot Synthesis of Nucleosides from Unprotected or 5-O-Monoprotected d -Ribose
Downey, A. Michael,Richter, Celin,Pohl, Radek,Mahrwald, Rainer,Hocek, Michal
supporting information, p. 4604 - 4607 (2015/09/28)
New, improved methods to access nucleosides are of general interest not only to organic chemists but to the greater scientific community as a whole due their key implications in life and disease. Current synthetic methods involve multistep procedures employing protected sugars in the glycosylation of nucleobases. Using modified Mitsunobu conditions, we report on the first direct glycosylation of purine and pyrimidine nucleobases with unprotected d-ribose to provide β-pyranosyl nucleosides and a one-pot strategy to yield β-furanosides from the heterocycle and 5-O-monoprotected d-ribose.
In search of flavivirus inhibitors: Evaluation of different tritylated nucleoside analogues
Chatelain, Grégory,Debing, Yannick,De Burghgraeve, Tine,Zmurko, Joanna,Saudi, Milind,Rozenski, Jef,Neyts, Johan,Van Aerschot, Arthur
supporting information, p. 249 - 255 (2013/10/01)
Following up on a hit that was identified in a large scale cell-based antiviral screening effort, a series of triphenylmethyl alkylated nucleoside analogues were synthesized and evaluated for their in vitro antiviral activities against the dengue virus (DENV) and the yellow fever virus (YFV). Hereto, trityl moieties were attached at various positions of the sugar ring combined with subtle variations of the heterocyclic base. Several triphenylmethyl modified nucleosides were uncovered being endowed with submicromolar in vitro antiviral activity against the YFV. The most selective inhibitor in this series was 3′,5′-bis-O-tritylated-5-chlorouridine (1b) affording a selectivity index of over 90, whereas the 3′,5′-bis-O-tritylated inosine congener (5b) displayed the highest activity, but proved more toxic. The finding of these lipophilic structures being endowed with high antiviral activity for flaviviruses, should stimulate the interest for further structureeactivity research.
A solvent free and selective method for preparation of triphenylmethyl ethers of alcohols and nucleosides
Zekri, Negar,Alamdari, Reza Fareghi,Khalafi-Nezhad, Ali
experimental part, p. 299 - 304 (2012/04/23)
A very simple and efficient method is described for protection of alcohols and nucleosides with trityl(triphenylmethyl), mono and dimethoxytrityl chlorides in the presence of triethylamine under microwave irradiation. High selectivity was observed for tritylation of 5'-OH function of nucleosides.
An efficient and selective method for the preparation of triphenylmethyl ethers of alcohols and nucleosides
Zekri, Negar,Alamdari, Reza Fareghi
experimental part, p. 563 - 568 (2010/08/05)
A very simple and efficient method is described for the protection of alcohols and nucleosides with benzyl monomethoxytrityl and benzyl dimethoxytrityl ethers in the presence of diethylazodicarboxylate and a catalytic amount of ceric triflate. High selectivity was observed for the tritylation of 5'-OH function of nucleosides.
Nucleosides. Part LI. The 2-(4-Nitrophenyl)ethoxycarbonyl (npeoc) and 2-(2,4-Dinitrophenyl)ethoxycarbonyl (dnpeoc) Groups for Protection of Hydroxy Functions in Ribonucleosides and 2'-Deoxyribonucleosides
Schirmeister, Helga,Himmelsbach, Frank,Pfleiderer, Wolfgang
, p. 385 - 401 (2007/10/02)
The common 2'-deoxypyrimidine and -purine nucleosides, thymidine (4), O4-thymidine (17), 2'-deoxy-N4-cytidine (26), 2'-deoxy-N6-adenosine (39), and 2'-deoxy-N2--O6-guanosine (52) were further protected by the 2-(4-nitrophenyl)ethoxycarbonyl (npeoc) and the 2-(2,4-dinitrophenyl)ethoxycarbonyl (dnpeoc) group at the OH functions of the sugar moiety to form new partially and fully blocked intermediates for nucleoside and nucleotide syntheses.The corresponding 5'-O-monomethoxytrityl derivatives 5, 18, 30, 40, and 56 were also used as starting material to synthesize some other intermediates which were not obtained by direct acylations.In the ribonucleoside series, the 5'-O-monomethoxytrityl derivatives 14, 36, 49, and 63 reacted with 2-(4-nitrophenyl)ethyl chloroformate (1) to the corresponding 2',3'-bis-carbonates 15, 37, 50, and 64 which were either detritylated to 16, 38, 51, and 65, respectively, or converted by 1,8-diazabicycloundec-7-ene (DBU) treatment to the 2',3'-cyclic carbonates 66-69.The newly synthesized compounds were characterized by elemental analyses and UV and 1H-NMR spectra.
Synthesis and Conformational Analysis of Phosphate-Methylated RNA Dinucleotides
Quaedflieg, Peter J. L. M.,Heiden, Arthur P. van der,Koole, Leo H.,Coenen, Annie J. J. M.,Wal, Sjoerd van der,Meijer, Emmo M.
, p. 5846 - 5859 (2007/10/02)
Synthesis of RNA dimers having a methyl phosphotriester group as the internucleoside linkage is reported; six pairs of diastereoisomerically pure systems were prepared, i.e., r(CpU) (15), r(ApU) (16), r(CpC) (17), r(ApC) (18), r(CpG) (19), and r(ApG) (20).Compounds 15-20 are stabilized by a 2'-O-methyl group in the 5'-terminal residue.The present systems represent the third class of backbone-modified RNA oligomers, following the 2'-O-methylribonucleotide phosphorothioates and the 2'-O-methylribonucleotide methyl phosphonates.Our synthetic approach comprises the use of 9-fluorenylmethoxycarbonyl (Fmoc) groups for transient protection of the exocyclic NH2 groups of the bases A, C, and G, levulinoyl (Lev) groups for the transient protection of the 2'- and 3'-OH groups of the 3'-terminal residue, methanolic K2CO3 for the simultaneous removal of Fmoc and Lev groups with full preservation of the methyl phosphotriester function, and finally reversed-phase HPLC separation of the SP and RP diastereoisomers.The availability of the six dimers in diastereoisomerically pure form enabled us to examine the molecular conformation using high-field NMR and circular dichroism (CD) spectroscopy.These studies led to the following conclusions: (i) NMR J-coupling analysis: the central C4'-C5' (γ) and C5'-O5' (β) bonds in 15-20 show less preference for the γ+ and βt rotamers, in comparison with their natural analogues, i.e., base stacking is diminished upon introduction of the two methyl groups on O2' and on the phosphate group; (ii) CD analysis: 15-20 show substantially reduced molecular ellipticities when compared to the natural counterparts, which also reveals that base stacking is reduced; (iii) UV and variable-temperature 1H NMR measurements: (SP)- and (RP)-19 show self-association, via the formation of a right-handed miniduplex with two C-G base pairs ((SP)-19, Tm = 9.3 deg C, concn = 36.6 μM; (RP)-19, Tm = 8.7 deg C, concn = 48.1 μM).The present conformational data on (RP)- and (SP)-15-20 are in agreement with literature data on other phosphate-triesterified oligonucleotides, e.g., the trimer d(TPOEtGPOEtG) and the tetramer d(TPOEtTPOEtCPOEtA).While the latter systems also showed little base-base stacking, it was estabished that they readily form a local duplex with a complementary natural RNA sequence.Hence we anticipate that phosphate-methylated 2'-O-methyl RNA oligomers, longer than the dimer systems described in the present work, will also hybridize easily with complementary natural RNA.
Nucleosides, XXXVII. - Synthesis and Properties of 2'-O- and 3'-O-(tert-Butyldimethylsilyl)-5'-O-(4-methoxytrityl)- and 2',3'-Bis(O-tert-butyldimethylsilyl)ribonucleosides - Starting Materials for Oligoribonucleotide Syntheses
Flockerzi, Dieter,Silber, Gunter,Charubala, Ramamurthy,Schlosser, Wilhelm,Varma, Rajendra Singh,et al.
, p. 1568 - 1585 (2007/10/02)
The synthesis of aminoacylated 5'-O-(4-methoxytrityl)ribonucleosides of adenosine (1), guanosine (9), cytidine (31), uridine (17), and 5,6-dihydrouridine (23) have been optimized and these compounds (4, 12, 33, 18 and 24) silylated by tert-butyldimethylsilyl chloride.The corresponding 2'- and 3'-mono-O- as well as 2',3'-bis-O-(tert-butyldimethylsilyl) derivatives have been isolated by combination of chromatographical methods and fractional crystallization procedures in preparative scale.The characterization of the newly synthesized compounds was achieved by UV and 13C-NMR spectra.
