The synthesis of a series of oligonucleotides containing 5-substituted pyrimidines as well as 7-substituted 7-deazapurines bearing diyne groups with terminal triple bonds is reported. The modified nucleosides were prepared from the corresponding iodo nucleosides and diynes by the Sonogashira cross-coupling reaction. They were converted into phosphoramidites and employed in solid-phase synthesis...

The chemical functionalization at C-5’ position of nucleosides has been significantly less studied compared to the C-1’, C-2’ and C-3’ sugar positions in spite its potential important role for biological activity. We describe here synthesis new carbothioate which were then engaged a Liebeskind-Srogl reaction with various boronic acids preparation diversely modified C-5’-acyl nucleosides. Applie...

The synthesis of 5' - deoxynucleoside 5' - phosphonates which contains a 5' - CP bond in place of the 5' -COP bond of the naturally occuring nucleotides is described. The preparation of phosphonate derivatives of acyclo - nucleosides and a simple method for the conversion of 1-? -D-ribofuranosyl pyrimidines to the corresponding 1-? -D-arabinofuranosyl pyrimidines are also explained

5-Alkylcytidine nucleosides were synthesized via a photocoupling reaction. 5-Propylcytidine and 5-propyl-2-deoxycytidine have been prepared through the reduction of 5-(3-propenyl)cytidine and its 2'-deoxy derivative, which in turn were prepared by photoirradiation of cytidine or 2'-deoxycytidine in the presence of 3-iodopropene. 5-(2-Hydroxyethyl)cytidine and its derivatives were obtained from ...

The chemistry of natural nucleosides and their analogues has been widely studied due to their potential as fungicidal, antitumor, and antiviral agents. 1 Consequently, extensive modifications have been made to both the heterocyclic base and the sugar moiety in order to avoid the drawbacks shown by nucleosides or analogues in certain applications. For organic chemists, enzymatic-catalyzed reacti...

The direct and chemoselective 3'-phosphoramidation, phosphorylation and acylation of nucleosides are described. Upon the discovery of a novel 3'-phosphorylamidation of therapeutic nucleoside analogues with DBU, we explored the mechanism of this rare selectivity through a combination of NMR spectroscopy and computational studies. The NMR and computational findings allowed us to develop a predict...

Research on metabolism of nucleotides and their derivatives has gained increasing interest in the recent past. This includes de novo synthesis, analysis of salvage pathways, breakdown and transport of nucleotides, nucleosides and nucleobases. To perform a further step towards the analysis of nucleoside transport in Arabidopsis, we incubated leaf discs with various radioactively labelled nucleos...

In this study, we describe the cloning and characterization of a proton-dependent, broadly selective nucleoside transporter from Caenorhabditis elegans. Recently, we constructed a broadly selective nucleoside transporter which accepts both purine and pyrimidine nucleosides. Based on these studies, we hypothesized that CNTs with novel substrate selectivities exist in nature and that a CNT homolo...

The present study was undertaken to determine the effect of nucleosides on nuclear and cytoplasmic maturation of mouse oocytes. Oocyte-cumulus complexes (OCCs) were collected from large antral follicles 4 h after eCG-hCG treatment and cultured in maturation medium with or without nucleosides (4 ribo- and 4 deoxyribonucleosides) for 12 h. A majority of the oocytes examined developed to the metap...

The 1H, 13C, and 15N NMR spectra of neutral and protonated forms of the nucleosides 1-methyladenosine (m1A), 7-methylguanosine (m7G) and ethenoadenosine (EA), as a model compound, have been analyzed in order to assign the site of protonation in m1A and m7G. Protonation of these nucleosides occurs in the pyrimidine ring of m1A and EA and in the imidazole ring of m7G, with the charge being distri...