Synthesis and Properties of α-Phosphate-Modified Nucleoside Triphosphates.

This review article is focused on the progress made in the synthesis of 5'-α-P-modified nucleoside triphosphates (α-phosphate mimetics). A variety of α-P-modified nucleoside triphosphates (NTPαXYs, Y = O, S; X = S, Se, BH, alkyl, amine, N-alkyl, imido, or others) have been developed. There is a unique class of nucleoside triphosphate analogs with different properties.

Phosphoramidate Azole Oligonucleotides for Single Nucleotide Polymorphism Detection by PCR.

Detection of the Kirsten rat sarcoma gene () mutational status is an important factor for the treatment of various malignancies. The most common -activating mutations are caused by single-nucleotide mutations, which are usually determined by using PCR, using allele-specific DNA primers. Oligonucleotide primers with uncharged or partially charged internucleotide phosphate modification have proved their ability to increase the sensitivity and specificity of various single nucleotide mutation detection.

Synthesis of Oligonucleotides Carrying Inter-nucleotide -(Benzoazole)-phosphoramide Moieties.

In this work, we present new oligonucleotide derivatives containing inter-nucleotide -benzimidazole, -benzoxazole, -benzothiazole, and 1,3-dimethyl--benzimidazole (benzoazoles) phosphoramide groups. These modifications were introduced via the Staudinger reaction with appropriate azides during standard automated solid-phase oligonucleotide synthesis. The principal structural difference between the new azido modifiers and those already known is that they are bulk heterocyclic structures, similar to purine nucleoside bases.

Synthesis of the new nucleoside 5'-alpha-iminophosphates using Staudinger reaction.

Efficient protocols were developed for the synthesis of a new compounds - nucleoside 5'-α-iminophosphates using the Staudinger reaction. These substances are alpha-phosphate mimetic nucleotide in which an oxygen atom is replaced by a corresponding imino (=N-R)-group. Various 5'-iminomonophosphates of nucleosides were obtained.

Data set on the synthesis and properties of 2',3'-dideoxyuridine triphosphate conjugated to SiO nanoparticles.

SiO nanoparticles were used as a transport system for cellular delivery of phosphorylated 2',3'-dideoxyuridine to increase its anticancer potency. This data set is related to the research article entitled "2',3'-Dideoxyuridine triphosphate conjugated to SiO nanoparticles: synthesis and evaluation of antiproliferative activity" (Vasilyeva et al., 2018) [1].

2',3'-Dideoxyuridine triphosphate conjugated to SiO nanoparticles: Synthesis and evaluation of antiproliferative activity.

A conjugate of triphosphorylated 2',3'-dideoxyuridine (ddU) with SiO nanoparticles was obtained via the CuAAC click chemistry between a γ-alkynyl ddU triphosphate and azido-modified SiO nanoparticles. Assessment of cytotoxicity in human breast adenocarcinoma MCF7 cells demonstrated that ddU triphosphate conjugated to SiO nanoparticles exhibited a 50% decrease in cancer cell growth at a concentration of 183 ± 57 µg/mL, which corresponds to 22 ± 7 µM of the parent nucleotide, whereas the parent nucleoside, nucleotide and alkynyl triphosphate precursor do not show any cytotoxicity. The data provide an example of remarkable potential of novel conjugates of SiO nanoparticles with phosphorylated nucleoside analogues, even those, which have not been used previously as therapeutics, for application as new anticancer agents.

DNA fluorescent labeling with naphtho[1,2,3-cd]indol-6(2H)-one for investigation of protein-DNA interactions.

Fluorescently labeled DNA to study protein-DNA interactions was synthesized using the Cu(I)-catalysed cycloaddition (CuAAC) reaction. For this purpose, a new azido-containing fluorophore based on the naphtho[1,2,3-cd]indol-6(2H)-one derivative was obtained. The fluorescent properties of naphtho[1,2,3-cd]indol-6(2H)-one derivatives and labeled DNA were studied.

Conjugates of phosphorylated zalcitabine and lamivudine with SiO nanoparticles: Synthesis by CuAAC click chemistry and preliminary assessment of anti-HIV and antiproliferative activity.

Conjugates of phosphorylated dideoxynucleoside antiviral drugs dideoxycytidine (zalcitabine) and lamivudine with SiO nanoparticles were obtained via the copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) click chemistry between a nucleoside triphosphate containing an alkynyl group at the γ-phosphate or azidothymidine triphosphate and SiO nanoparticles containing alkyl azide or alkynyl groups, respectively. 4-(Prop-2-yn-1-yloxy)butylamino group has been attached to the γ-phosphate group of dideoxycytidine (zalcitabine) and lamivudine 5'-triphosphates via the phosphoramidate linkage. New compounds were shown to be potent killers of human colon carcinoma cells.

Application of Cu(I)-catalyzed azide-alkyne cycloaddition for the design and synthesis of sequence specific probes targeting double-stranded DNA.

Efficient protocols based on Cu(I)-catalyzed azide-alkyne cycloaddition were developed for the synthesis of conjugates of pyrrole-imidazole polyamide minor groove binders (MGB) with fluorophores and with triplex-forming oligonucleotides (TFOs). Diverse bifunctional linkers were synthesized and used for the insertion of terminal azides or alkynes into TFOs and MGBs. The formation of stable triple helices by TFO-MGB conjugates was evaluated by gel-shift experiments.

On Field-Effect Photovoltaics: Gate Enhancement of the Power Conversion Efficiency in a Nanotube/Silicon-Nanowire Solar Cell.

Recent years have seen a resurgence of interest in crystalline silicon Schottky junction solar cells distinguished by the use of low density of electronic states (DOS) nanocarbons (nanotubes, graphene) as the metal contacting the Si. Recently, unprecedented modulation of the power conversion efficiency in a single material system has been demonstrated in such cells by the use of electronic gating. The gate field induced Fermi level shift in the low-DOS carbon serves to enhance the junction built-in potential, while a gate field induced inversion layer at the Si surface, in regions remote from the junction, keeps the photocarriers well separated there, avoiding recombination at surface traps and defects (a key loss mechanism).

SiO₂ nanoparticles as platform for delivery of 3'-triazole analogues of AZT-triphosphate into cells.

A system for delivery of analogues of AZT-triphosphates (AZT*TP) based on SiO₂ nanoparticles was proposed. For this purpose, a simple and versatile method was developed for the preparation of SiO₂∼dNTP conjugates using the 'click'-reaction between AZTTP and premodified nanoparticles containing the alkyne groups. The substrate properties of SiO₂∼AZT*TP were tested using Klenow fragment and HIV reverse transcriptase.

Novel fluorescent pyrimidine nucleosides containing 2,1,3-benzoxadiazole and naphtho-[1,2,3-CD] Indole-6 (2H)-one fragments.

A series of novel fluorescent pyrimidine nucleosides containing 2,1,3-benzoxadiazole or naphtho[1,2,3-cd]indole-6 (2h)-one fragments was designed and synthesized. Introduction of fluorescent fragments into the position 5 of the uridine or cytidine heterocycle was carried out in two ways: by Sonogashira Coupling Reaction and CuI-catalyzed cycloaddition ("click" reaction). The obtained nucleoside derivatives became fluorescent due to the inserted fragments.

Extraordinary hydrogen evolution and oxidation reaction activity from carbon nanotubes and graphitic carbons.

The hydrogen evolution reaction, 2H(+) + 2e(–) → H2, and its converse, the hydrogen oxidation reaction, H2 → 2H(+) + 2e(–), are central to any realization of a hydrogen economy. Various forms of carbon have been used for decades as the precious metal catalyst support in these reactions. Here we report the unexpected result that single-wall carbon nanotubes and some graphitic carbons, activated by brief exposure to electrochemical potentials that induce hydrogen evolution in intercalating acids combined with extended soak times in such acids, acquire an activity for these reactions that exceeds that of known nonprecious metal catalysts.

Oligonucleotide functionalization by a novel alkyne-modified nonnucleosidic reagent obtained by versatile building block chemistry.

A convenient synthetic strategy has been designed to prepare an alkyne-modified synthon for automated DNA synthesis. It is based on the key O-DMTr-protected 4-(2-hydroxyethyl)morpholin-2,3-dione and building blocks obtained by its functionalization by various aliphatic amines. A respective nonnucleosidic phosphoramidite monomer containing a terminal alkyne in the side-chain was synthesized, and corresponding oligothymidylates incorporating the modification in various positions were prepared.

SiO₂ nanoparticles as platform for delivery of nucleoside triphosphate analogues into cells.

A system for delivery of analogues of 2'-deoxyribonucleoside triphosphate (dNTP) based on SiO(2) nanoparticles was proposed. A simple and versatile method was developed for the preparation of SiO(2)-dNTP conjugates using the 'click'-reaction between premodified nanoparticles containing the azido groups and dNTP containing the alkyne-modified γ-phosphate group. The substrate properties of SiO(2)-dNTP were tested using Klenow fragment and HIV reverse transcriptase.

Synthesis of novel nucleoside 5'-triphosphates and phosphoramidites containing alkyne or amino groups for the postsynthetic functionalization of nucleic acids.

A series of novel nucleoside 5'-triphosphates and phosphoramidites containing alkyne or amino groups for the postsynthetic functionalization of nucleic acids were designed and synthesized. For this purpose, the new 3-aminopropoxypropynyl linker group was used. It contains two alternative functional capabilities: an amino group for the reaction of amino-alkynyl-modified oligonucleotides with corresponding activated esters and an alkyne group for the copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction.

Material strategies for black-to-transmissive window-type polymer electrochromic devices.

Black-to-transmissive switching polymer electrochromic devices (ECDs) were designed using a set of spray-processable cathodically coloring polymers, a non-color-changing electroactive polymer poly(2,2,6,6-tetramethylpiperidinyloxy-4-yl methacrylate) (PTMA) as the charge-compensating counter electrode, and a highly conducting gel electrolyte (6.5 mS cm(-1)). The color "black" was obtained by utilizing (1) individual copolymers absorbing across the visible spectrum, and (2) blends and bilayers of several polymer electrochromes with complementary spectral absorption.

Color purity in polymer electrochromic window devices on indium-tin oxide and single-walled carbon nanotube electrodes.

Dual polymer absorptive/transmissive electrochromic (EC) window devices have been assembled using the solution-processable and high-EC-contrast polymer PProDOT-(CH(2)OEtHx)(2) as the EC material, along with a non-color-changing electroactive polymer, poly(2,2,6,6-tetramethylpiperidinyloxy-4-yl methacrylate) (PTMA), as the counter electrode material. Indium-tin oxide (ITO) and highly transmissive single-walled carbon nanotube (SWNT) film coated glass electrodes are used as electrode substrates. The use of the EC/non-color-changing polymer combination allowed us to construct window devices that rapidly switch between magenta and highly transmissive (>95% T for ITO and approximately 79% T for SWNT) states with large optical modulation (>71% DeltaT for ITO and 66% DeltaT for SWNT).

Metallocene-containing conjugated polymers.

The paper gives a review of publications on polymers with conjugated matrices (PPy, PTh, PAni, hydrocarbon or mixed chains...

Synthesis of monomers bearing at the 2'-position cyanomethoxycarbonyl group for phosphoramidite oligonucleotide synthesis.

A novel series of phosphoroamidites for the synthesis of 2-modified oligonucleotides was designed and synthesized on the base of 2'-amino uridine and 2'-amino arabinoadenosine. The amino groups in these compounds were acidified by bis-cyanomethyl esters of different dicarbonic acids. Generated reactive linker groups containing cyanomethoxycarbonyl groups are stable under conditions of oligonucleotide synthesis but could be easily functionalised in post-synthetic stage by treatment with compounds bearing primary amino groups.