A series of 5-substituted 1-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)cytosines 7a-d and their corresponding uracils 9a-d,f were prepared by condensation of 3-O-acetyl-5-O-benzoyl-2-deoxy-2-fluoro-D-arabinosyl bromide (5) with appropriately trimethylsilylated pyrimidines followed by saponification of the protected nucleosides 6 or 8. 1-(2-Deoxy-2-fluoro-beta-D-arabinofuranosyl)-5-iodocytosine (7e) was obtained by iodination of 7a. Iodination of 8a followed by removal of the protecting acyl-protecting groups afforded the 5-iodo nucleoside 9e. Several of these 2'-fluoro-substituted nucleosides completely obviated replication of herpes simplex virus type 1 (HSV-1) in monolayers of Vero cells at concentrations of 10-100 microgram/mL. The 5-iodocytosine analogue 7e was the most effective, showing 99.5% suppression of viral replication even at concentrations of 0.1 microgram/mL. The cytotoxicity of 7e to L5178Y or P815 cells in culture was minimal. A comparison of the efficacy of 7e against HSV-1 with other known nucleoside antiviral agents indicates that further in vitro and in vivo evaluation of 7e is warranted.

The first science flight of the balloon-borne Sunrise telescope took place in June 2009 from ESRANGE (near Kiruna/Sweden) to Somerset Island in northern Canada. We describe the scientific aims and mission concept of the project and give an overview and a description of the various hardware components: the 1-m main telescope with its postfocus science instruments (the UV filter imager SuFI and the imaging vector magnetograph IMaX) and support instruments (image stabilizing and light distribution system ISLiD and correlating wavefront sensor CWS), the optomechanical support structure and the instrument mounting concept, the gondola structure and the power, pointing, and telemetry systems, and the general electronics architecture. We also explain the optimization of the structural and thermal design of the complete payload. The preparations for the science flight are described, including AIV and ground calibration of the instruments. The course of events during the science flight is outlined, up to the recovery activities. Finally, the in-flight performance of the instrumentation is discussed.

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International audienceThe Concordiasi project is making innovative observations of the atmosphere above Antarctica. The most important goals of the Concordiasi are as follows: 1. To enhance the accuracy of weather prediction and climate records in Antarctica through the assimilation of in situ and satellite data, with an emphasis on data provided by hyperspectral infrared sounders. The focus is on clouds, precipitation, and the mass budget of the ice sheets. The improvements in dynamical model analyses and forecasts will be used in chemical-transport models that describe the links between the polar vortex dynamics and ozone depletion, and to advance the understanding of the Earth system by examining the interactions between Antarctica and lower latitudes. 2. To improve our understanding of microphysical and dynamical processes controlling the polar ozone, by providing the first quasi-Lagrangian observations of stratospheric ozone and particles, in addition to an improved characterization of the 3D polar vortex dynamics. Techniques for assimilating these Lagrangian observations are being developed. A major Concordiasi component is a field experiment during the austral springs of 2008-10. The field activities in 2010 are based on a constellation of up to 18 long-duration stratospheric super-pressure balloons (SPBs) deployed from the McMurdo station. Six of these balloons will carry GPS receivers and in situ instruments measuring temperature, pressure, ozone, and particles. Twelve of the balloons will release drop-sondes on demand for measuring atmospheric parameters. Lastly, radiosounding measurements are collected at various sites, including the Concordia station

6073neutral fraction (495 mg.) separated from it. The benzenesoluble part of the neutral fraction (340 mg.) dissolved in a small volume of benzene was poured onto a column of 20 g.of Fisher alumina and the chromatogram developed with absolute petroleum ether. The first 10 fractions (each 50 ml.) yielded 137 mg. of colorless oil which was converted into the trinitrobenzene complex. This compound was repeatedly crystallized from ethanol to a constant melting point of 157°; the yield of the analytically pure sample was 30 mg. This melting point is 20°h igher than the melting point of l-methyl-7-ethylphenanthrene trinitrobenzolate and no depression of melting point was observed on admixture of an authentic sample of pimanthrene trinitrobenzolate which melted also at 157°. The sample was decomposed by chromatography on a small column of alumina and the crystalline hydrocarbon sublimed for infrared and ultraviolet spectrum. These were identical with the spectra of an authentic specimen of pimanthrene.

A newly synthesized pyrimidine analog, 2'-fluoro-5-iodo-aracytosine (FIAC), suppressed by 90% the replication of various strains of herpes simplex virus types 1 and 2 at concentrations of 0.0025 to 0.0126 ,M. Cytotoxicity was minimal, as determined by trypan blue dye exclusion with normal Vero, WI-38, and NC-37 cell proliferation; the 50% inhibitory dose was 4 to 10 ,uM in a 4-day assay. When compared with other antiviral drugs, FIAC was active at much lower concentrations than arabinosylcytosine, iododeoxyuridine, and arabinosyladenine. It was slightly more active against herpes simplex virus type 1 than acycloquanosine and slightly more toxic to normal cells. FIAC was about 8,000 times more-active against the replication of wild-type herpes simplex virus type 1 than against a mutant strain lacking the expression of virus-specified thymimdine kinase. Since FIAC appears to be preferentially phosphorylated by the viral enzyme, this is probably responsible, at least in part, for the selectivity of its antiviral actions. Although FIAC appears to be an arabinosylcytosine analog, its antiviral activity was not reversed by deoxycytidine. The minimal cytotoxicity exhibited by FIAC for normal cells, however, was reversed by equimolar concentrations of deoxycytidine. Thymidine, which reversed the antiviral activity, was effective only when used in great excess.Biochemical studies with the herpesviruses have revealed that infection of susceptible cells in a culture leads to the expression of at least one, and possibly two or more, enzymes coded for by the infecting virus (1, 5-7, 9-13). Infection with herpes simplex virus type 1 (HSV-1), HSV-2, herpes zoster virus (HZV), cytomegalovirus, or Epstein-Barr virus results in the expression of a new deoxyribonucleic acid polymerase that has properties different from those of the normal cellular enzymes (1, 5, 9, 11-13). In addition, HSV-1, HSV-2, and HZV also induce a virusspecific nucleotide kinase (4, 6, 7, 10), whereas cytomegalovirus induces increased expression of cellular thymidine kinase. Although these enzymes are thought to be coded for by the infecting virus, proof of this has been obtained only for HSV-1 (7, 13). These virus-specified enzymes appear to have substrate requirements which differentiate them from normal cellular enzymes and which, therefore, make them excellent targets for the development of selective antiviral chemotherapeutic drugs (2, 3).Recently, Watanabe et al. (14) (14). In this report, we present further studies ofthe capacity of FIAC to suppress replication of HSV-1, HSV-2, and HZV and present evidence which indicates that the selectivity demonstrated by FLAC probably depends on the virus-specified nucleotide kinase.MATERIALS AND METHODS Virus strains. Most experiments with HSV-1 were carried out with strain 2931, which was isolated and characterized previously (8). Other HSV-1 strains included the Patton strain (obtained from M. Bernhardt, Sloan-Kettering Institute), the MacIntyre strain (obtained from the American Type Culture Collection), and ...