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81.
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We report a general synthetic approach to the preparation of highly functionalized amine and amino acid derivatives of [60]fullerene starting from readily available chlorofullerene C(60)Cl(6). The synthesized water-soluble amino acid derivative of C(60) demonstrated pronounced antiviral activity, while the cationic amine-based compound showed strong antibacterial action in vitro.  相似文献   
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Abstract

In this article, we present the preparation, characterization, and catalytic performance of bimetallic Co93Fe07 and Ni80Fe20 active mass loaded on synthetic nanodiamonds (SNDs) in the carbon dioxide (CO2) methanation. The pristine SNDs possessing a developed specific surface are thermally stable and inert to the reaction mixture of CO2 and dihydrogen. However, it is shown that 100% conversion of CO2 into methane can be reached at the lower temperature than that for a massive Co93Fe07 or Ni80Fe20 catalyst when 20?wt.% of the catalyst mass was loaded on the surface of SNDs. The catalytic activity of the prepared bimetallic/SNDs composites is estimated as the minimum temperature at the maximum conversion of CO2 at atmospheric pressure: it is 325 and 290?°C for Co93Fe07/SNDs and Ni80Fe20/SNDs, respectively. Thermal desorption studies showed that the methanation over Co-Fe/SNDs and Ni-Fe/SNDs catalysts run through the stage of CO2 dissociation into carbon and oxygen atoms and their subsequent interaction with hydrogen to form methane and water molecules. Scanning electron microscopy studies have shown that the presence of transition metal-rich sites on the surface of the carrier contributes to the improvement of efficiency of the Ni80Fe20 catalyst action.  相似文献   
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The crystal structures of 5-nitro- and 5-ethoxycarbonyl-substituted 6-phenyl-4-(3-fluorophenyl)-3,4-dihydro-(1H)-pyrimidin-2-ones were determined by X-ray diffraction analysis. Conformational peculiarities of the structures have been revealed and compared with data for other biologically active dihydropyrimidinones.  相似文献   
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Based on structural data of lipid A from Chlamydia trachomatis strains, chemically pure tetra- and pentaacyl 1,4′-bisphosphoryl as well as the related 4′-monophosphoryl derivatives of lipid A were synthesized. (R)-3-Hydroxyicosanoic acid as a chiral constituent was prepared via Noyori-reduction of methyl-3-oxoicosanoic acid. Synthetic intermediates were O-acylated with myristoic acid residues at positions 3 and 3′ and N-acylated with (R)-3-hydroxyicosanoic acid at both glucosamine units. Efficient purification methods for highly hydrophobic long-chain tri-, tetra- and pentaacyl progenitors of lipid A have been developed. Purity and homogeneity of the synthetic target compounds were confirmed by NMR and MS-data as well as a sensitive immunostaining approach. The tetra- and pentaacyl species serve as biomedical probes to investigate the endotoxic potential of chlamydial lipid A and to clarify its role in Chlamydia associated infections.  相似文献   
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