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121.
[structure: see text] An efficient total stepwise solid-phase synthesis of oligonucleotide-(3'-->N)-peptide conjugates is described that makes use of either a controlled pore glass support or macroporous polystyrene beads. Extending our previous homoserine linker approach, we prepared a range of conjugates containing one of four different cell or nuclear penetration peptides together with oligonucleotides containing 2'-deoxynucleoside or 2'-O-methylribonucleoside phosphodiesters, or gapmers containing 2'-deoxyphosphorothioates. The route also allows incorporation of a fluorescent label within the conjugate for cell uptake studies. 相似文献
122.
123.
Solodovnikov S. P. Tumanskii B. L. Bashilov V. V. Lebedkin S. F. Sokolov V. I. 《Russian Chemical Bulletin》2002,51(6):1009-1014
The ESR spectra of the products of oxidation of solutions and powders of Y@C82 and La@C82 with fuming sulfuric acid were studied. Based on the oxidation conditions and the sequence of spectral patterns, the spectra were attributed to the radical cations M@C82
n+ (n = 2, 4), dimers M3+
2@C164
+, and polyendometallofullerenes. 相似文献
124.
1-(2-Oxiranyl)-1,4-alkanediones were prepared from the ethylene acetals of ethyl 4-oxoalkanoates via the oxidation of the intermediate 1,2-dialkylcyclopropanols having a protected carbonyl group in an aliphatic chain. Intramolecular acetalization of these epoxy dicarbonyl compounds gave alkylated 6,8-dioxabicyclo[3.2.1]octan-2-ones in good yields. The latter were found suitable to be precursors for (±)-endo-brevicomin and its 2-hydroxy derivative, as well as (±)-endo-isobrevicomin and (±)-frontalin. 相似文献
125.
126.
Alexander S. Lyakhov Dmitry O. Ivashkevich Sergei V. Voitekhovich Pavel N. Gaponik 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(12):m563-m564
The title compound, [CuCl2(C5H11N5)], is the first structurally characterized molecular chelate complex involving an α‐aminoalkyltetrazole. There are two complex molecules in the asymmetric unit. The ligand molecules are bidentate. Both Cu atoms reveal rather distorted square‐planar coordinations. The complex molecules are linked together by van der Waals interactions only. 相似文献
127.
L. F. Chertanova B. I. Buzykin A. A. Gazikasheva M. P. Sokolov 《Russian Chemical Bulletin》1992,41(12):2162-2167
The crystal and molecular structures of the products of the halogenation of the dimorpholide of ethoxyvinylphosphonic acid were determined by the method of x-ray structure analysis. It was established that (dimorpholinophosphoryl)chloroacetaldehyde only exists in the crystals as the Z-enol [(Z)-1-hydroxy-2-(dimorpholinophosphoryl)-2-chloroethene] with intra- and intermolecular H-bonds (=CH...O=P and OH...O=P). The (dimorpholinophosphoryl)dibromomethane forms centrosymmetric eight-membered cyclic dimers in the crystals due to intermolecular CH...O=P H-bonds. The structure of the morpholine and phosphoryl groups in both compounds was discussed.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan' Scientific Center, Russian Academy of Sciences, 420083 Kazan'. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 12, pp. 2730–2737, December, 1992. 相似文献
128.
Dmitry Yu. Naumov Natalia V. Kuratieva 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(1):i9-i10
The structure of rhombohedral (R) iron(III) tris[dihydrogenphosphate(I)] or iron(III) hypophosphite, Fe(H2PO2)3, has been determined by single‐crystal X‐ray diffraction. The structure consists of [001] chains of Fe3+ cations in octahedral sites with symmetry bridged by bidentate hypophosphite anions. 相似文献
129.
Dmitry A. Zyuzin Svetlana V. Cherepanova Elena B. Burgina Victor G. Kostrovskii 《Journal of solid state chemistry》2006,179(10):2965-2971
Genesis of the structure of zirconia particles prepared by precipitation of amorphous hydrated zirconia by ammonia from the ZrO(NO3)2 solution followed by a mild hydrothermal treatment (HTT) of precipitate, washing and calcination under air up to 1000 °C has been studied by X-ray diffraction (XRD), Raman and FTIRS. As revealed by FTIRS of lattice modes, the local structure of amorphous zirconia subjected to HTT is close to that in m-ZrO2. This helps to obtain nearly single-phase monoclinic nanozirconia (particle size 5-15 nm) already after a mild calcination at 500 °C. Stability of this phase with nanoparticles sizes below the critical value determined by thermodynamic constraints is due to its excessive hydroxylation demonstrated by FTIRS. Dehydroxilation and sintering of these nanoparticles at higher (600-650 °C) temperatures of calcination leads to reappearance of the (111) “cubic” reflection in XRD patterns. Modeling of XRD patterns revealed that this phenomenon could be explained by polysynthetic (001) twinning earlier observed by HRTEM. 相似文献
130.
T. V. Mitkina D. Yu. Naumov O. A. Gerasko F. M. Dolgushin C. Vicent R Llusar M. N. Sokolov V. P. Fedin 《Russian Chemical Bulletin》2004,53(11):2519-2524
The inclusion compound of macrocyclic cavitand cucurbit[8]uril (CB[8]) with the nickel(II) complex containing the tetraazamacrocyclic ligand cyclam, {[Ni(cyclam)]@CB[8]}Cl2··16H2O (1), and the inclusion compounds of CB[8] with the copper(II) bis-ethylene-diamine complex, {trans-[Cu(en)2(H2O)2]@CB[8]}Cl2·{CB[8]}·42H2O (2a) and {trans-[Cu(en)2(H2O)2]@CB[8]}Cl2·17H2O (2b), were synthesized and characterized by X-ray diffraction analysis, IR and ESR spectroscopy, and electrospray mass spectrometry. Guest—host inclusion compounds can be directly synthesized starting from a metal complex and cucurbit[8]uril, as was exemplified by the preparation of compounds 2a and 2b.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2414–2419, November, 2004. 相似文献