Synthesis of 2-amino-5-nitro-4H-pyran-3-carbonitriles

Reaction of 2-carbomethoxy-ω-nitroacetophenone with arylmethylenemalononitriles gives the previously unknown 2-amino-4-aryl-5-nitro-6-(2-carbomethoxyphenyl)-4H-pyran-3-carbonitriles. N. D. Zelinskii Institute of Organic Chemistry, Russian Academy of Sciences, Moscow 117913. E-mail: muskat@cacr.ioc.ac.ru. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1661–1663, December, 1998.     

An electrochemical signal switch–based (on–off) aptasensor for sensitive detection of insulin on gold-deposited screen-printed electrodes

Journal of Solid State Electrochemistry - Insulin hormone is of great importance for many diseases, especially for diabetes management. Therefore, different detection strategies have been used for...     

Reactions of sulfur ylides with α,β-unsaturated thioamides: Synthesis of dihydrothiophenes and cyclopropanes

The reactions of stabilized sulfonium ylides with arylmethylenecyanothioacetamides proceed stereoselectively to yield 2-amino-4,5-dihydrothiophenes and cyclopropane-thiocarboxamides. The structures of the latter compounds were confirmed by X-ray diffraction analysis.     

Synthesis and structure of 2-amino- 5-azolyl-3-cyano-4H-pyrans

Previously unknown 5-azolylpyrans were obtained by reactions ofN-acetonyl- andN-phenacylimidazoles, -triazoles, and -tetrazoles with arylmethylenemalononitriles. The structure of 2-amino-3-cyano-6-methyl-5-(5-nitrotetrazol-2-yl)-4-phenyl-4H-pyran was established by X-ray structural analysis.Deceased.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 2050–2055, August, 1996.     

Lightlike Hypersurfaces of a Golden Semi-Riemannian Manifold

We introduce lightlike hypersurfaces of a golden semi-Riemannian manifold. We investigate several properties of lightlike hypersurfaces of a golden semi-Riemannian manifold. We prove that there is no radical anti-invariant lightlike hypersurface of a golden semi-Riemannian manifold. In particular, we obtain some results for screen semi-invariant lightlike hypersurfaces of a golden semi-Riemannian manifold. Moreover, we study screen conformal screen semi-invariant lightlike hypersurfaces.     

Arylglyoxal oximes as putative C-nucleophiles in eliminative nucleophilic substitution process

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Synthesis and Crystal Structure of Mixed-valence Hexanuclear Manganase Oxide Complex,Hexakis(μ<Subscript>2</Subscript>-pivalato)-tetrakis(μ<Subscript>3</Subscript>-pivalato)-mono(pyridine)-tris(pivalic acid)-bis(μ<Subscript>4</Subscript>-oxo)dimanganese(III) tetramanganase(II)

Abstract  The complex, [Mn₆O₂(OOCCMe₃)₁₀(HOOCCMe₃)₃(py)], has a hexanuclear structure with a Mn₆O₂ core. This complex crystallizes in the monoclinic space group P2₁/n with a = 17.757(5) ?, b = 27.413(5) ?, c = 22.348(5) ?, β = 90.233(5)°, V = 9,040(4) ?³ and Z = 4. It contains a [Mn₆O₂]¹⁰⁺ core that can be described as two edge-sharing Mn₄ tetrahedra at the centre of each of which tetrahedron lies a μ₄-O²⁻ ion. All Mn atoms are six-coordinate and possess distorted octahedral geometry. Mn₄ exhibits butterfly arrangement with both μ₄-O atoms on the same side of the molecule. The complex is mixed-valence , and the Mn^III centers are assigned as the two central metal ions bridged by two O²⁻ ions. Index abstract  The complex, [Mn₆O₂(OOCCMe₃)₁₀(HOOCCMe₃)₃(py)], has a hexanuclear structure with a Mn₆O₂ core. This complex crystallizes in the monoclinic space group P2₁/n with a = 17.757(5) ?, b = 27.413(5) ?, c = 22.348(5) ?, β = 90.233(5)°, V = 9040(4) ?³ and Z = 4. It contains a [Mn₆O₂]¹⁰⁺ core that can be described as two edge-sharing Mn₄ tetrahedra at the centre of each of which tetrahedron lies a μ₄-O²⁻ ion. All Mn atoms are six-coordinate and possess distorted octahedral geometry. Mn₄ exhibits butterfly arrangement with both μ₄-O atoms on the same side of the molecule. The complex is mixed-valence , and the Mn^III centers are assigned as the two central metal ions bridged by two O²⁻ ions.