Victor A. Timoshchuk

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The polymerase chain reaction (PCR) is widely used for applications which require a high level of specificity and reliability, such as genetic testing, clinical diagnostics, blood screening, forensics and biodefense. Great improvements to PCR performance have been achieved by the use of Hot Start activation strategies that aim to prevent DNA polymerase(More)
A new method for the synthesis of fluorescent nucleosides has been developed. It has been shown that a reaction of benzoquinone with aminopropenyl group at C-5-position of 2'-deoxyuridine or 2'-deoxycytidine and aminopropynyl group at the C-7-position of 8-aza-7-deazaadenosine under extremely mild conditions affords conjugated benzoxazole derivatives of(More)
Long single-stranded DNAs and RNAs possess considerable secondary structure under conditions that support stable hybrid formation with oligonucleotides. Consequently, different oligomeric probes can hybridize to the same target with efficiencies that vary by several orders of magnitude. The ability to enzymatically generate structure-free single-stranded(More)
At present, the chemistry of spatially screened phenols is being extensively developed. This fact is explained both by the practical value of these compounds (antioxidants, radiation protectors, drugs) and their role in investigations of the fundamental biochemical reactions in the cell, since these processes frequently involve reversible reactions of the(More)
The bioantioxidant activity of the synthesized by us on the base of the diatomic phenol compound--3,5-di-t-butylpyrocatechol--has been studied. It was shown that this substance exhibits more pronounced antioxidant properties than tocopherol on the lipid peroxidation process in the rat brain homogenate appears in concentrations right up to 10(-8)-10(-7) M.(More)
The effects of hypoxia on the morphological and functional parameters are studied in confluent cultures of astrocytes derived from the brain of newborn rats. Morphofunctional alterations emerge 16–20 h after hypoxia and manifest themselves as nuclear and cellular hypertrophy, cell vacuolization, and decreased mitotic activity. The intensity of alterations(More)
The goal of this work is to produce high yields of long-lived AQ(*-)/dA(*+) charge transfer (CT) excited states (or photoproducts). This goal fits within a larger context of trying generally to produce high yields of long-lived CT excited states within DNA nucleoside conjugates that can be incorporated into DNA duplexes. Depending upon the energetics of the(More)
A straightforward enzymatic protocol for converting regular DNA into pseudo-complementary DNA could improve the performance of oligonucleotide microarrays by generating readily hybridizable structure-free targets. Here we screened several highly destabilizing analogs of G and C for one that could be used with 2-aminoadenine (nA) and 2-thiothymine (sT) to(More)
N4-Benzoylcytosine 1-(methyl 2,3,4-tri-O-acetyl-β-D-glucopyranosiduronate) has been obtained with a yield of 70% by the glycosylation of the trimethylsilyl derivative of N4-benzoylcytosine with methyl 1,2,3,4-tetra-O-acetyl-β-D-glucopyranuronate in the presence of three equivalents of SnCl4 as condensing agent. Cytosine 1-(β-D-glucopyranosiduronamide) (IV)(More)
A study of C-nucleophilic substitution at the C4-position on pyrimidine and C6-position on 2'-deoxyguanosine to produce novel nucleosides is presented with the spectroscopic properties of their respective substitution products. C4-(1,2,4-triazol-1-yl) pyrimidine nucleosides 1 were treated with nitroalkanes, malononitrile, acetylacetone, ethyl nitroacetate,(More)