- Incorporation of Sulfate or Selenate Groups into Oxotellurates(IV): I. Calcium, Cadmium, and Strontium Compounds
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Seven new mixed oxochalcogenate compounds in the systems MII/XVI/TeIV/O/(H), (MII= Ca, Cd, Sr; XVI= S, Se) were obtained under hydrothermal conditions (210 °C, one week). Crystal structure determinati
- Weil, Matthias,Shirkhanlou, Mahdi
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- Incorporation of Sulfate or Selenate Groups into Oxotellurates(IV): II. Compounds with Divalent Lead
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Four mixed oxochalcogenate compounds in the systems PbII/XVI/TeIV/O/(C), (XVI = S and Se) were obtained as minority phases under hydrothermal conditions (210 °C, one week). Their compositions as determined on the basis of single-crystal X-ray diffraction data are Pb3(SeO4)(TeO3)2, Pb7O4(SeO4)2(TeO3), Pb5(SeO4)2(TeO4)(CO3), and Pb2(SO4)(TeO3). All crystal structures are centrosymmetric, and in each case the oxochalcogenate anions are isolated from each other. The Pb2+ cations exhibit distorted coordination polyhedra with coordination numbers ranging from six to ten, in the majority of cases with a “one-sided” coordination by oxygen atoms. The presence of the very rare square-pyramidal TeIVO44– anion distinguishes the structure of Pb5(SeO4)2(TeO4)(CO3) from the other structures, where the oxotellurate(IV) anions exist in the TeO32– trigonal-pyramidal configuration.
- Weil, Matthias,Shirkhanlou, Mahdi
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- Incorporation of Sulfate or Selenate Groups into Oxotellurates(IV): III. Compounds with Magnesium or Zinc
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The mixed oxochalcogenate compounds Mg2(SO4)(TeO3)(H2O), Mg3(SO4)(TeO3)(OH)2(H2O)2, Zn2(SeO4)(TeO3), and Zn4(SO4)(TeO3)3 were obtained under hydrothermal conditions (210 °C, autogenous pressure). Structure analyses using single-crystal X-ray data revealed tellurium in all four compounds to be present in oxidation state +IV, whereas sulfur or selenium atoms exhibit an oxidation state of +VI. In the crystal structures of the two magnesium compounds, [MgO5(H2O)] octahedra [Mg2(SO4)(TeO3)(H2O) structure, isotypic with the Co and Mn analogues] or [MgO4(OH)2] and [MgO4(OH)2(H2O)2] octahedra [Mg3(SO4)(TeO3)(OH)2(H2O)2structure, novel structure type] as well as trigonal-pyramidal TeO32– anions make up metal oxotellurate sheets, which are bridged by SO42– anions. The polar crystal structure of Zn2(SeO4)(TeO3) is isotypic with Zn2(MoO4)(TeO3) and consists of [ZnO4] tetrahedra, [ZnO6] octahedra, SeO42– and TeO32– anions as principal building units that are connected into a framework structure. Such a structural arrangement, with basically the same coordination polyhedra as in Zn2(SeO4)(TeO3) but with SO42– instead of SeO42– anions, is also found in the tellurium-rich compound Zn4(SO4)(TeO3)3 that crystallizes in a novel structure type.
- Weil, Matthias,Shirkhanlou, Mahdi
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- Containing selenium compound of cordycepin salt and its preparation and use
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The invention relates to a cordycepin salt containing a selenium compound, a preparation method of the cordycepin salt and an application. The structure of the cordycepin salt containing the selenium compound is shown in a general formula (I), and n=1 or 2, x=3 or 4. The cordycepin salt containing the selenium compound has a high anti-tumor effect.
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Paragraph 0058; 0059
(2018/05/16)
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- For anticancer containing selenium compound and its preparation and use
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The invention relates to an anticancer analgesic selenium-containing compound and a preparation method and an application thereof. The structure of the selenium-containing compound is as shown in the general formula (I), wherein n=1 or 2, x=2 or 4; and chiral center (*) is R/S-(+/-) or S-(-) configuration. The selenium-containing compound provided by the invention has anticancer and analgesic functions, has a more excellent analgesic effect than tetrahydropalmatine or rotundine, can be used in cancer pain, even cancer pain in middle and advanced stage, has no addition and can be used to effectively improve life quality of patients.
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Paragraph 0065; 0066
(2017/12/01)
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- Synthesis and structure of cyclic selenium oxide SeVISe2IVO7
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Nitromethane is the only presently known organic solvent for highly reactive selenium trioxide (SeO3)4. The stability of the solutions is limited and the beginning of the reaction between both components depends significantly on conc
- Touzin,Kilian,Zak
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p. 1617 - 1622
(2008/10/09)
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