Results 121 to 130 of about 451 (159)

The structures of furazans and furoxans

Chemistry of Heterocyclic Compounds, 1966
The IR spectra of furazans and furoxans are characterized by lowered values of frequencies and of integrated absorption band intensities for the C=N bands. The peculiarities of the UV absorption spectra of these compounds are similar to those of pyridine and its benzene analogs in comparison with the corresponding N-oxides.
B. E. Zaitsev, Z. V. Todres, V. A. Pozdyshev   +2 more
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Mass spectra of furoxans

Journal of Heterocyclic Chemistry, 1964
AbstractThe mass spectra of furoxans have large NO+ peaks due to the fragmentation of the ring system at C‐N and N‐O bonds. Cleavage of the substituents and to a smaller extent ring fission at C3‐C4 account for other ion peaks. The spectra are sufficiently characteristic to serve for the identification of these compounds.
H. E. Ungnade, E. D. Loughran
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Toward an Understanding of the Furoxan−Dinitrosoethylene Equilibrium

Journal of the American Chemical Society, 2001
The tautomerism of furoxan (1,2,5-oxadiazole-2-oxide) has been investigated by different computational methods comprising modern density functionals as well as single-reference and multi-reference ab initio methods. The ring-opening process to 1,2-dinitrosoethylene is the most critical step of the reaction and cannot be treated reliably by low-level ...
J, Stevens, M, Schweizer, G, Rauhut
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Synthesis and Properties of Unsubstituted Furoxan

Mendeleev Communications, 1994
For the first time a synthesis of unsubstituted furoxan, the first member of the furoxan series, has been accomplished.
Tamara I. Godovikova, Svetlana P. Golova, Yurii A. Streienko, Mikhail Yu. Antipin, Yurii T. Struchkov, Lenor I. Khmeĺnitskii   +5 more
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Steroid 16,17-furoxan derivatives

Canadian Journal of Chemistry, 1968
The syntheses of 3-methoxy-l,3,5(10)-estratrieno[16,17-c]furoxan (3) and 3-keto-4-androsteno[16, 17-c]furoxan (8) from 16-oximinoestrone methyl ether and 16-oximino-5-androsten-3β-ol-17-one, respectively, are described.
Hans Reimann, Helen Schneider
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Nonclassical furoxans — A computational study

Tetrahedron, 1996
Ab initio and density functional theoretical studies on nonclassical furoxans (4a-c; 9, 10; 15, 16; 21a, b; 23, 24) and some of their open-chain o-dinitroso isomers (5a-c; 6a-c; 7a-c; 11–14; 17–20; 22a, b; 25, 26) are presented.
Burkhard Klenke, Willy Friedrichsen
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Properties of furoxans monosubstituted with adamantanes

Chemistry of Heterocyclic Compounds, 1988
Furoxans monosubstituted with a series of adamantanes have been obtained by oxidation of anti-[1-(3-R-adamantyl)]-amphi-glyoximes. Depending on the conditions 4-(1-adamantyl)furoxan is partially isomerized to 3-(1-adamantyl)furoxan or by increasing the time of boiling and concentration of furoxan in p-xylene is isomerized to the thermodynamically ...
M. I. Kalinina, I. K. Moiseev
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Reactions of furoxans with phosphorus ylides

Tetrahedron, 1986
Abstract Benzofuroxan ( 1 ) reacts with phosphorus ylide 2 to give benzimidazole derivatives 8 and 10 , Whereas reaction of 1 with ylide 12 furnishes quinoxaline 17 via an Initial Wittig-type reaction. Similarly the reaction between the furoxano[3.4-b]quinoxalines 19a or 19b and the ylide 2 ...
N.G. Argyropoulos, J.K. Gallos, D.N. Nicolaides   +2 more
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ChemInform Abstract: FUROXANS AS NITRILE OXIDE PRECURSORS: CYCLOADDITION REACTIONS OF BIS(BENZENESULFONYL)FUROXAN

Chemischer Informationsdienst, 1982
AbstractAus Bis‐benzolsulfonyl‐furoxan (III) erhält man beim Erhitzen mit den Olefinen (II) oder Cyclohexen (IV) die Isoxazoline (I) bzw. (V).
R. A. WHITNEY, E. S. NICHOLAS
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?-Bromoacetyl derivatives of furazan and furoxan

Russian Chemical Bulletin, 1993
Bromination of acetylfurazans and furoxans has been studied. The conditions for the synthesis of bromoacetyl derivatives have been found.
A. B. Sheremetev, A. S. Kulikov, L. I. Khmel'nitskii   +2 more
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