Results 171 to 180 of about 4,245 (200)

The new era of 1,2,4-oxadiazoles

Organic & Biomolecular Chemistry, 2009
The synthesis, the chemical and photochemical reactivity, and the use of 1,2,4-oxadiazoles in materials and as bioactive compounds have been reviewed. The material in this survey includes some historical background, general features, state-of-the-art applications together with a critical discussion about current limitations and suggestions for future ...
PACE, Andrea, PIERRO, Paola
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Polydifluoromethylene-bis-1,2,4-oxadiazoles

Bulletin of the Academy of Sciences, USSR Division of Chemical Science, 1966
1. The reaction of the nitriles of perfluorodicarboxylic acids with hydroxylamine gave the amidoximes of perfluoroglutaric, perfluoroadipic and perfluorosebacic acids. 2. 5,5′-Alkyl-3,3′-polydifluoromethylene-bis-1,2,4-oxadiazoles are easily formed when the amidoximes of the perfluoroglutaric, perfluoroadipic and perfluorosebacic acids ...
I. L. Knunyants, M. P. Krasuskaya, D. P. Del'tsova   +2 more
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Synthesis of 3‐Carbamoyl‐1,2,4‐oxadiazoles.

ChemInform, 2002
AbstractFor Abstract see ChemInform Abstract in Full Text.
V. N. Yarovenko, S. A. Kosarev, I. V. Zavarzin, M. M. Krayushkin   +3 more
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Liquid Crystalline Pyridine Containing 1,2,4-Oxadiazoles

Molecular Crystals and Liquid Crystals Science and Technology. Section A. Molecular Crystals and Liquid Crystals, 2001
New mesomorphic 1,2,4-oxadiazoles containing as an electron-acceptor substituent the pyridine cycle with different position of the nitrogen atom with respect to the oxadiazole cycle have been synthesized. The reaction of the isonicotinic and nicotinic amidoximes with various acid chlorides smoothly provided the corresponding mesogenic 3-(4-pyridinyl ...
L. A. KARAMYSHEVA, I. F. AGAFONOVA, S. I. TORGOVA, B. A. UMANSKII, STRIGAZZI, Alfredo   +4 more
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ChemInform Abstract: 3,5‐DISUBSTITUTED‐1,2,4‐OXADIAZOLES AND 4,5‐DIHYDRO‐3,5‐DISUBSTITUTED‐1,2,4‐OXADIAZOLES

Chemischer Informationsdienst, 1979
AbstractAus den Amidoximen (IV) erhält man mit Säurechloriden die Oxadiazole (II), die mit Borwasserstoff zu den Dihydroverbindungen (I) reduziert werden.
H. L. YALE, E. R. SPITZMILLER
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Fluorinated banana-shaped 1,2,4-oxadiazoles

SPIE Proceedings, 2002
A series of banana-shaped diesters derivated of 3,5-bis-(p- hydroxyphenyl)-1,2;4-oxadiazole and p-alkyloxy- fluoro(difluoro)benzoic acids were synthesized and investigated by optical microscopy and DSC method. The influence of the alkyloxy-substituent lengths and of the F- group position in the molecule on its mesomorphic properties is discussed.
L. A. Karamysheva, I. F. Agafonova, T. A. Geivandova, Sofia I. Torgova, M. Becchi   +4 more
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New synthesis of 1,2,4-oxadiazoles

Tetrahedron, 1990
The interaction of amidoximes with nitriles in the presence of ZnCl 2 and HCl affords 1,2,4-oxadiazoles. The reaction of N-15-labeled amidoximes with nitriles was studied. Elimination of the amino group of the amidoxime fragment was observed in the oxadiazole formation and N-monoalkyl and N,N-dialkylamidoximes can be used in the synthesis of 1,2,4 ...
V.N. Yarovenko, V.K. Taralashvili, I.V. Zavarzin, M.M. Krayushkin   +3 more
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Some trans-phenylazo-1,2,4-oxadiazoles

Journal of the Chemical Society, Perkin Transactions 1, 1974
Some trans-phenylazoformamide oximes (4) have been prepared from trans-benzenediazocyanides (3) and hydroxylamine, and converted into trans-3-phenylazo-1,2,4-oxadiazoles (5) by reaction with amide acetals or trialkyl orthoformates. Some 5-unsubstituted 3-phenylazo-1,2,4-oxadiazoles have been reduced to 3-amino-1-aryl-1,2,4-triazoles (8), but di-imide ...
Jack A. Maddison, Peter W. Seale, Edward P. Tiley, William K. Warburton   +3 more
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Synthesis of glycosyl-triazole linked 1,2,4-oxadiazoles

Carbohydrate Research, 2007
The synthesis of four different types of oxadiazoles containing a terminal acetylenic group is described. Reaction of these oxadiazoles with various azidoglycosides via a copper-catalyzed [3+2] cycloaddition ('click chemistry') afforded the corresponding glycosyl-triazole linked 1,2,4-oxadiazoles in good yields.
Janaína V, dos Anjos, Denis, Sinou, Sebastiao J, de Melo, Rajendra M, Srivastava   +3 more
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Tandem Reactions of 1,2,4-Oxadiazoles with Allylamines

Organic Letters, 2011
A reaction of 3-chloro-1,2,4-oxadiazoles with allylamine and diallylamine has been investigated. 3,3a,4,5-Tetrahydroisoxazolo[3,4-d]pyrimidines are produced through a tandem ANRORC/[3 + 2]cycloaddition pathway consisting of the addition of allylamine to the 1,2,4-oxadiazole, followed by ring opening, nitrone formation, and finally cycloaddition.
PALUMBO PICCIONELLO, Antonio, PACE, Andrea, BUSCEMI, Silvestre   +2 more
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