共查询到20条相似文献,搜索用时 0 毫秒
1.
Pavol Kois Zdenek Tocik Maria Spassova Wu-Yun Ren Ivan Rosenberg Jaume Farras Soler 《Nucleosides, nucleotides & nucleic acids》2013,32(10):1093-1109
Abstract In order to find the effects of unnatural nucleosides on the stability of duplex, several oligonucleotides containing 1-(2-deoxy-2-fluoro-β-D-arabinofuranosyl)-uracil(FAU),-cytosine (FAC) and -thymine (FMAU) were synthesized by two alternative approaches: phosphoramidite method on an ABI 392 synthesizer and H-phosphonate procedure on our GeneSyn I universal module synthesizer. It was shown from the melting profiles that the presence of FMAU has a large stabilizing effect on the duplex. Replacement of thymidine with FAU, or deoxycytidine with FAC resulted in the formation of less stable duplexes. Temperature-dependent CD spectroscopy demonstrated that the structures of the fluorine containing oligomers are very similar to those of unmodified oligomers. 相似文献
2.
Abstract The use of the Fmoc group for the protection of the hydroxy functions of the sugar moiety gave an improved overall yield of 2′-deoxy-5-azacytidine (6β), due to the mildly-basic conditions required for its removal from the protected nucleoside. 相似文献
3.
Ramon Eritja Victor E. Marquez Ramon Güimil García 《Nucleosides, nucleotides & nucleic acids》2013,32(7-9):1111-1114
Abstract The preparation of a protected derivative of 5-aza-2′-deoxycytidine carrying the 2-(p-nitrophenyl)ethyl group is described. The new derivative is useful for the preparation of oligonucleotides containing 5-aza-2′-deoxycytidine using a special methodology that avoids the use of ammonia. 相似文献
4.
Ekambar R. Kandimalla Jamal Temsamani Sudhir Agrawal 《Nucleosides, nucleotides & nucleic acids》2013,32(3-5):1031-1035
Abstract 2′-O-methylribonucleoside methylphosphonamidites are synthesized and incorporated into oligonucleotides to obtain chimeric antisense oligonucleotides. The resulting oligonucleotide binds to their target RNA/DNA sequences efficiently and stable in a medium containing bovine serum. 相似文献
5.
Natalya Ramzaeva Helmut Rosemeyer Frank Seela 《Nucleosides, nucleotides & nucleic acids》2013,32(3-5):947-950
Abstract The rate and velocity of the photoconversion of 2-chloro-2′-deoxyadenosine into 2′-deoxyisoguanosine within oligonucleotides was found to be sequence-specific and depends on the nearest neighbor. 相似文献
6.
Laureen C. Colis Debasis Chakraborti Pablo Hilario Christopher McCarty Ashis K. Basu 《Nucleosides, nucleotides & nucleic acids》2013,32(2):67-77
Two different approaches to synthesize oligonucleotides containing the 2 ′-deoxyguanosine adducts formed by nitropyrenes are described. A direct reaction of an unmodified oligonucleotide with an activated nitropyrene derivative is a convenient biomimetic approach for generating the major adducts in DNA. A total synthetic approach, by contrast, involves several synthetic steps, including Buchwald-Hartwig Pd-catalyzed coupling, but can be used for incorporating both the major and minor adducts in DNA in high yield. 相似文献
7.
Darya S. Novopashina Olesya S. Totskaya Maria I. Meschaninova Dmitry A. Stetsenko Alya G. Venyaminova 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):821-825
We have developed a new method for the preparation of oligodeoxyribonucleotides and oligo(2′-O-methylribonucleotides) that contain a 2′-phosphorylated ribonucleoside residue, and optimized it to avoid 2′ -3′ -isomerization and chain cleavage. Structures of the 2′ -phosphorylated oligonucleotides were confirmed by MALDI-TOF MS and enzymatic digestion, and the stability of their duplexes with DNA and RNA was investigated. 2′-Phosphorylated oligonucleotides may be useful intermediates for the introduction of various chemical groups for a wide range of applications. 相似文献
8.
《Nucleosides, nucleotides & nucleic acids》2013,32(5-8):635-639
Abstract A facile synthesis of oligodeoxynucleotides (ODN) containing 2′-deoxy-6-thioinosine (dI6S) based on the convertible nucleoside O6-phenyl-2′-deoxyinosine is presented. After standard solid-phase DNA synthesis and removal of the cyanoethyl protecting groups with DBU treatment with aqueous sodium hydrogen sulfide introduces the sulfur functionality, deprotects the other nucleobases and cleaves the ODN from the solid support in a one-pot reaction. In addition, the extinction coefficient of 2′-deoxy-6-thioinosine is determined by enzymatic fragmentation of the resulting ODN in the presence of adenosine deaminase. 相似文献
9.
P. Herdewijn R. Charubala R. Pauwels E. De Clercq W. Pfleiderer 《Nucleosides, nucleotides & nucleic acids》2013,32(1-2):441-442
Abstract The antiviral activity of (E)-5-(2-bromovinyl)-2′-deoxyuridine (BVdUrd), acyclovir and other antiherpetic nucleosides depends on a selective phosphorylation by the herpesvirus-induced thymidine kinase in the infected cells. Viruses not encoding a specific thymidine kinase (TK) activity are resistant to the action of these nucleoside analogues. The nucleoside monophosphates are as such poorly taken up by the cells. In order to circumvent the necessity of intracellular phosphorylation, we synthesized four core oligonucleotides bearing a biological active nucleoside at the 2′end. It was hypothesized that these core oligonucleotides, like core 2–5A itself, would be taken up within the cell and that, following intracellular 2′-5′ phosphodiesterase cleavage, the 5′-monophosphate of the active product would be formed. In these circumstances, activity against TK- strains could be expected. 相似文献
10.
《Nucleosides, nucleotides & nucleic acids》2013,32(5-8):1383-1385
Abstract Oligonucleotides carrying 2′-aldehyde groups were synthesized and coupled to peptides containing an N-terminal cysteine, aminooxy or hydrazide group to give peptide-oligonucleotide conjugates in good yield. The synthesis of a novel phosphoramidite reagent for the incorporation of 2′-O-(2,3-diaminopropyl)uridine into oligonucleotides was also described. Resultant 2′-diaminooligonucleotides may be useful intermediates in further peptide conjugation studies. 相似文献
11.
《Nucleosides, nucleotides & nucleic acids》2013,32(5-8):1159-1161
Abstract 3′-Deoxy-3′-C-methyleneuridine nucleoside 1 1 has been incorporated into oligodeoxynucleotides. Relative to the unmodified references, oligomers containing nucleoside 1 displayed reduced binding affinities towards complementary DNA and RNA with a tendency towards RNA-selective hybridization. 相似文献
12.
Andrew M. Kawasaki Martin D. Casper Thazha P. Prakash Sheri Manalili Henri Sasmor Muthiah Manoharan 《Nucleosides, nucleotides & nucleic acids》2013,32(6-7):1419-1420
Abstract We have synthesized the novel 2′-O-AOE- and MIOE-5-methyluridine and -adenosine nucleosides and successfully incorporated them into oligonucleotides. The 2′-O-modifications significantly enhance hybridization against RNA (1.2 deg C/substitution) and furthermore, exhibits specificity for RNA vs. DNA. The nuclease resistance (SVPD) of 2′-O-AOE and MIOE modified oligonucleotides is comparable to that of 2′-O-MOE. 相似文献
13.
14.
Prasanna Jayalath Subhash Pokharel Eduardo Véliz Peter A. Beal 《Nucleosides, nucleotides & nucleic acids》2013,32(2):78-88
The RNA-editing adenosine deaminases (ADARs) catalyze deamination of adenosine to inosine in double stranded structure found in various RNA substrates, including mRNAs. Here we describe the synthesis of a phosphoramidite of 2 ′-deoxy-2 ′-mercaptoadenosine and its incorporation into an ADAR substrate. Surprisingly, no deamination product was observed with this substrate indicating replacing the 2 ′-OH with a 2 ′-SH at the editing site is highly inhibitory. Modeling of nucleotide binding into the active site suggests the side chain of T375 of human ADAR2 to be in proximity of the 2 ′-substituent. Mutation of this residue to cysteine caused a greater that 100-fold reduction in deamination rate with the 2 ′-OH substrate. 相似文献
15.
Bruce S. Ross Guillermo Vasquez Sheri Manalili Elena Lesnik Richard Griffey 《Nucleosides, nucleotides & nucleic acids》2013,32(7-9):1547-1549
Abstract A short multigram synthesis of 2′-O-methylpseudouridine and its phosphoramidite derivative is described which avoids the use of protecting groups on the nitrogens. A binding study of oligonucleotides containing this modification suggest an increased binding affinity to RNA when compared to oligonucleotides incorporating 2′-O-methyluridine. 相似文献
16.
V. Bhat B. C. Ugarkar K. Grirara E. Stocker P. A. Domenico V. A. Sayeed 《Nucleosides, nucleotides & nucleic acids》2013,32(8):1061-1065
Abstract A convenient synthesis of 2′,3′-dideoxycytidine (ddC, 6) from 2′-deoxycytidine (1) has been achieved employing a base-catalyzed elimination of 3′-O?methanesulfonyl group as the key step. 相似文献
17.
《Nucleosides, nucleotides & nucleic acids》2013,32(5-8):1251-1254
Abstract We present procedures for nucleoside and oligonucleotide synthesis, binding affinity (T m) and structural analysis (CD spectra) of 2′-deoxy-2′,2″-difluoro-α-D-ribofuranosyl and 2′-deoxy-2′,2″-difluoro-β-D-ribofuranosyl oligothymidylates. Possible reasons for the thermal instability of duplexes formed between these compounds and RNA or DNA targets are discussed. 相似文献
18.
Xiao Liu Xueliang Xia Chenghai Sun Cai Lin Yiqian Zhou Muzammal Hussain 《Nucleosides, nucleotides & nucleic acids》2016,35(9):479-494
The preparation of 2′-deoxy-2′-siprodifluorocyclopropany-lnucleoside analogs has been achieved from α-d-glucose in several steps. The key step in the synthesis was the introduction of the difluorocyclopropane through a difluorocarbene type reaction at the 2′-position. Then, a series of novel 2′-deoxy-2′-spirodifluorocyclopropanyl nucleoside analogs were synthesized using the Vorbrüggen method. All the synthesized nucleosides were characterized and subsequently evaluated against hepatitis C and influenza A virus strains in vitro. 相似文献
19.
Palmarisa Franchetti Loredana Cappellacci Mario Grifantini Giulio Lupidi Giuseppe Nocentini Anna Barzi 《Nucleosides, nucleotides & nucleic acids》2013,32(5):1059-1076
Abstract The syntheses of 7-amino-3-(β-D-ribofuranosyl)-3H-1,2,3-triazolo[4,5-b]pyridine (8-aza-1-deazaadenosine) (2) and 7-amino-3-(2-deoxy-β-D-erythro-pentofuranosyl)-3H-1,2,3-triazolo[4,5-b]pyridine (2′-deoxy-8-aza-1-deazaadenosine) (3) by glycosylation of the anion of 7-chloro-3H-1,2,3-triazolo[4,5-b]pyridine are described. The anomeric configuration as well as the position of glycosylation were determined by 1H, 13 NMR, UV and N.O.E. difference spectroscopy. The cytotoxicity of these nucleosides against several murine and human tumor cell lines is discussed. Compounds 2 and 3 proved to be good inhibitors of adenosine deaminase. 相似文献
20.
Anna V. Kachalova Timofei S. Zatsepin Elena A. Romanova Dmitry A. Stetsenko Michael J. Gait Tatiana S. Oretskaya 《Nucleosides, nucleotides & nucleic acids》2013,32(10-12):1693-1707
Abstract Chemical syntheses of 2′-O-(allyloxycarbonyl)methyladenosine, 2′-O-(methoxycarbonyl)methyladenosine and 2′-O-(2,3-dibenzoyloxy)propyluridine 3′-2-cyanoethyl-N,N-diisopropyl phosphoramidite building blocks are described. These monomers were used successfully to incorporate carboxylic acid, 1,2-diol and aldehyde functionalities into synthetic oligonucleotides. 相似文献