[Antiherpesviral activity of acycloguanosine H-phosphonate in experiments using laboratory animals].

A study of the antiherpesviral activity of acycloguanosine (ACG) H-phosphonate (ACG-P) on a model of fatal herpesvirus infection in inbred BALB/c albino mice has established that ACG-P reduces death rates in the animals, considerably increases their average lifespan, and significantly decreases brain virus titers with both 60% mortality in the control and 92% mortality in the control group. There was also a significant inhibition of herpes simplex virus type 1 (HSV-1) replication in the brain tissue of animals receiving ACG-P on a model of ACG-resistant HSV-1/L2/RACG(TK-).

[Cloning, expression, isolation and properties of thymidine kinase herpes simplex virus, strain L2].

A thymidine kinase UL23 gene (EC 2.7.1.145) from an acyclovir-sensitive strain L2 of herpes simplex virus type 1 was cloned and expressed in E. coli. Enzyme was purified by chromatography to a homogeneous state controlled by PAG electrophoresis. The Michaelis constants for the reactions with thymidine and an acyclovir were determined. It was found that enzyme phosphorilate some modified nucleosides such as d2T, d4T, d2C, 3TC, FLT, BVDU, GCV. A comparison of the purified enzyme properties and properties ofthymidine kinase of other strains of herpes simplex virus, previously published was carried out. It is shown that enzyme is inhibited by acyclovir H-phosphonate.

[Phosphoramidate derivatives of acyclovir--herpes virus replication inhibitors].

A number of new phosphoramidates of acyclovir--compounds of interest as anti-virals against resistant strains of virus herpes was synthesized. Several methods of synthesis of these compounds were suggested. Optimal method appeared to be the obtaining of phosphoramidates through the phosphomonocloride with its subsequent treatment with various amines. Two compounds have shown moderate activity against HSV-1.

[Comparative study of resistance to acycloguanosine and acycloguanosine H-phosphonate in herpes simplex virus].

The ability of acycloguanosine H-phosphate to inhibit the reproduction of herpes simplex virus type 1 (HSV-1) variants, including its acycloguanosine (acyclovir)-resistant ones, was studied. Acycloguanosine H-phosphate-resistant HSV-1 variants were obtained. It was found that these variants were cross-resistant to thymidine kinase-dependent HSV reproduction inhibitors, but preserved sensitivity to Apa-A and phosphonoacetic acid.

[The erythrocyte and plasma glutathione system under peptic ulcer].

In erythrocytes and blood plasma of patients with the complicated peptic ulcer and postresectional syndromes there was the increase of conjugated dienes (and in the second group the increase in antioxidant activity). Under these conditions the main change was the sharp and identical decrease in glutathione activity. In patients with uncomplicated peptic ulcer there was sharp increase in erythrocyte and plasma glutathione activity and plasma GSH. In operated but basically healthy patients plasma glutathione peroxidase remained decreased but plasma GSH sharply increased. Evidently complicated peptic ulcer is characterized by decreased functioning of the glutathione system. Activation of this system and the decrease or disappearance of manifestations of oxidative stress are associated with a favorable course of this disease, especially at uncomplicated peptic ulcer. The revealed changes significantly differ from those observed in viral hepatitis, bile excretory treat diseases and strokes.

[New derivatives of alkyl- and aminocarbonylphosphonic acids containing 3'-azido-3'-deoxythymidine].

New 5'-phosphonates of 3'-azido-3'-deoxythymidine were synthesized and shown to be low-toxic and markedly active in MT-4 cell cultures infected with HIV-1.

[Enzymatic synthesis of bis(5'-nucleosidyl) tetra- or triphosphates].

The total fraction of aminoacyl-tRNA synthases from Escherichia coli has been shown to catalyze the synthesis of the bis(5'-nucleosidyl) oligophosphates Ap4AZT, Ap4d4T, Ap43TC, and Ap4ACV, as well as Ap3AZT and Ap3d4T, from [alpha-32P]ATP and the corresponding nucleoside-5'-tri(or di)phosphate. The resulting compounds, characterized by HPLC, are resistant to alkaline phosphatase. Ap4AZT, Ap4d4T, and Ap43TC are formed with approximately equal efficiency, whereas the efficiencies of the synthesis of Ap4ACV, Ap3AZT, and Ap3d4T are three- to fivefold lower. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2005, vol. 31, no. 6; see also http://www.maik.ru.

[New non-nucleoside substrates for terminal deoxynucleotidyl transferase: the synthesis and the dependence of substrate properties on structure].

N-(9-Fluorenylmethoxycarbonyl)-omega-aminoalkyl, N-(9-fluorenylmethoxycarbonyl)-8-amino-3,6-dioxaoctyl, and N-(9-fluorenylmethoxycarbonyl)-6-aminohexanoyl]-2-aminoethyl triphosphates were synthesized. All of them were shown to be the substrates of the calf thymus terminal deoxynucleotidyl transferase. Their substrate properties depend on the length and structure of linker between the 9-fluorenylmethoxycarbonyl and triphosphate moieties.

[Synthesis and antiherpetic activity of (Z)- and (E)-isomers of 9-(3-phosphonomethoxyprop-1-en-yl)adenine].

9-(3-Phosphonomethoxyprop-1-en-yl)adenine (Z)- and (E)-isomers were synthesized. The stereoselectivity of double bond formation was studied by variation of sulfonyl groups. The resulting phosphonates exhibited a moderate antiherpetic activity in a culture of Vero cells infected with herpes simplex type 1 virus. The Z-isomer was shown to be more effective inhibitor of virus reproduction in the case of both wild and acyclovir-resistant strain.

[Antiviral activity of vegetable triterpens, their derivatives and ribavirin phosphonates]. / Protivovirusnaia aktivnost' triterpenov rastitel'nogo proiskhozhdeniia, ikh proizvodnykh i fosfonatov ribavirina.

The purpose of the study was to investigate, in the Vero cell culture, the antiviral activity of vegetable tritrpens derivatives and ribavirin analogues against the viruses of measles, herpes simple (type 1), cytomegaloviruses and filoviruses. The toxicity and antiviral activity of compounds were determined after coloring of cells with crystal violate. Additionally, the combined action of triterpens' derivatives and ribavirin was investigated. The studied compounds showed relatively low antiviral activity, nonetheless, further research of vegetable triterpens and their derivatives as well as ribavirin analogues would be promising.

[The synthesis and antiherpetic activity of acyclovir phosphonate esters]. / Sintez i antigerpeticheskaia aktivnost' fosfonatnykh éfirov atsiklovira.

Alkyl esters of acyclovir phosphite, alkoxycarbonylphosphonate, ethoxycarbonylmethylphosphonate, and aminocarbonylphosphonate were synthesized. Most of them were shown to inhibit the replication of type 1 herpes simplex virus in Vero cell culture. The stability in phosphate buffer and human blood serum was studied for several of the derivatives. A correlation between the stability and antiviral activity of the synthesized compounds is discussed. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2004, vol. 30, no. 6; see also http://www.maik.ru.

[New phosphonoformic acid derivatives of 3'-azido-3'-deoxythymidine]. / Novye proizvodnye 3'-azido-3'-dezoksitimidina i fosfonomurav'inoi kisloty.

New 5'-alkyl ethoxy- and aminocarbonylphosphonates of 3'-azido-3'-deoxythymidine (AZT) were synthesized, and their antiviral properties in HIV-1-infected cell cultures and stability to chemical hydrolysis were studied. The AZT 5'-aminocarbonylphosphonates were shown to be significantly more stable in phosphate buffer (pH 7.2) than the corresponding ethoxycarbonylphosphonates. The therapeutic (selectivity) index of some of the compounds exceeded that of the parent AZT due to their higher antiviral activity. The English version of the paper: Russian Journal of Bioorganic Chemistry, 2004, vol. 30, no. 3; see also http://www.maik.ru.

[Synthesis of beta-H-phosphono-alpha-phosphonomethyl analogues of nucleoside 5'-diphosphates]. / Sintez beta-H-fosfonometil'nykh analogov nukleozid-5'-difosfatov.

Novel beta-H-phosphono-alpha-phosphonomethyl analogues of nucleoside 5'-diphosphates were synthesized by phosphonylation of 5'-O-phosphonomethylthymidine and 9-[2-phosphonomethyloxy)ethyl]adenine with sodium pyrophosphite. The structures of the resulting individual compounds were confirmed by NMR and UV spectroscopy.

[Preparation of 32P-labelled 2-methylthioadenosine di- and triphosphates]. / Poluchenie 32-P-mechenykh di- i trifosfatov 2-metiltioadenozina.

2-Methylthioadenosine 5'-mono- and diphosphates were prepared by chemical synthesis, and enzymatically phosphorylated to 5'-[beta-32P]-diphosphate and 5'-[gamma-32P]-triphosphate, respectively. They were isolated by HPLC and had activity exceeding 1000 Ci/mmol and radiochemical purity higher than 95%.

[Phosphorylation of 5'-O-phosphonylmethylthymidine and its incorporation into HeLa cells DNA]. / Fosforilirovanie 5'-O-fosfonilmetiltimidina i ego vkliuchenie v DNK kletok HeLa.

[3H]5'-O-Phosphonylmethylthymidine with a specific activity of 71 Ci/mmol was obtained by isotope exchange. Its incubation with a HeLa cell culture resulted in the formation of [3H]-labeled 5'-O-(beta-phosphoryl-alpha-phosphonylmethyl)thymidine, 5'-O-(beta,gamma-diphosphoryl-alpha-phosphonylmethyl)thymidine, and [3H]DNA. This proved the ability of 5'-O-phosphonylmethylthymidine to undergo phosphorylation and incorporation into the DNA of human cells.

[Synthesis and antiherpes activity of acyclovir phosphoesters]. / Sintez i antigerpeticheskaia aktivnost' fosfornykh éfirov atsiklovira.

9-(Hydroxyethyloxymethyl)guanine (acyclovir) phosphite and fluorophosphate were synthesized by the reactions of acyclovir with phosphorus trichloride in triethyl phosphate and with fluorophosphoric acid in the presence of 2,4,6-triisopropylbenzenesulfonyl chloride, respectively, and characterized by the data of 1H and 31P NMR and mass spectra. These products selectively inhibit reproduction of the herpes simplex virus type 1 in the Vero cell culture, the phosphite being also substantially active against a herpes virus strain resistant to acyclovir.

[Synthesis and some biochemical properties of phosphonyl acyclic analogs of 2'-deoxyadenosine nucleotides]. / Sintez i nekotorye biokhimicheskie svoistva fosfonil'nykh atsiklicheskikh analogov 2'-dezoksiadenozinovykh nukleotidov.

9-[2-(phosphonomethylcarbonylamino)ethyl]adenine, 9-[(2-phosphonoethyl)aminocarbonylmethyl]adenine, 9-[2-[(2-phosphonoethyl)carbonylamino]ethyl]adenine, and their diphosphates were synthesized. All three diphosphates were shown to incorporate into the 3'-terminus of the DNA chain during the synthesis of the avian myeloblastosis virus catalyzed by reverse transcriptase. However, they do not serve as substrates for DNA polymerase alpha from human placenta, polymerase beta from calf thymus, or terminal deoxynucleotidyl transferase from calf thymus.

[New nucleotide inhibitors of human DNA polymerase alpha]. / Novye nukleotidnye ingibitory DNK-polimerazy alpha cheloveka.

2'-Deoxythymidine 5'-triphosphate and 2'-deoxyadenosine 5'-triphosphate analogs containing a methylene group between the alpha phosphorus and 5' oxygen were synthesized. The substrate properties of these compounds toward some mammalian DNA polymerases and retroviral reverse transcriptases were evaluated using a system containing phage M13mp10 DNA, a synthetic oligonucleotide, and the enzyme. The compounds containing a hydroxyl at the 3' position were incorporated into the DNA chain by DNA polymerase alpha and terminal deoxynucleotidyl transferase, but were not recognized by retroviral reverse transcriptases and mammalian DNA polymerases epsilon and beta. The selectivity of the compounds synthesized was capitalized on during simultaneous isolation of DNA polymerases alpha and epsilon from human placenta. A methylene group was also introduced into the acyclovir molecule. It was shown that this modification inactivates furanose-related nucleotide analogs, but has a minor effect on the substrate properties of acyclic nucleotide analogs.

[Conformation of crystalline 3'-nitro-2',3'-dideoxythymidine and properties of its 5'-triphosphate as a terminator substrate of retroviral reverse transcriptase]. / Konformatsiia 3'-nitro-2',3'-didezoksitimidina v kristalle i svoistva ego 5'-trifosfata kak terminatornogo substrata obratnykh transkriptaz retrovirusov.

The structure of new nucleoside--3'-nitro-2',3'-dideoxythymidine (NIT) possessing moderate anti HIV activity in MT-4 cell culture was investigated by X-ray analysis. These data showed that conformation of NIT in crystal is similar to that of one of crystallographically independent forms of 3'-azido-2',3'-dideoxythymidine. 3'-Nitro-2',3'-dideoxythymidine 5'-triphosphate (NITTP) was synthesized and its ability to inhibit human and viral DNA polymerases was studied. NITTP proved to be effective and highly selective terminating substrate of DNA synthesis catalyzed by HIV and AMV reverse transcriptases. Human DNA polymerase alpha as well as DNA polymerase beta (rat liver), terminal deoxynucleotidyltransferase (calf thymus) or HSV-1 and CMV DNA polymerases did not incorporate NITTP into a growing DNA chain.