New synthesis of 1,2,4-oxadiazoles (original) (raw)
Related papers
ChemInform, 1997
The cycloaddition of nitrile oxides to amidoximes is a general method for the sinthesis of 3,5disubstituted 1,2,4-oxadia.zole-4oxides with the same or different substituents. The yields are only moderate since an equivalent amount of the nitrile oxide is consumed by reaction with the amine released in the fragmentation of the primary cycloadducts and reforms the amidoxime. With excess nitrile oxides the 1,2,4-oxadiazole-4+=kies undergo a dispropotionation reaction to yield nitroso carbnyl intermediates and 1,2,4_oxadiazoles. 0 1997, Elsevier Science Ltd. All rights reserved.
Tetrahedron, 1997
The cycloaddition of nitrile oxides to amidoximes is a general method for the sinthesis of 3,5disubstituted 1,2,4-oxadia.zole-4oxides with the same or different substituents. The yields are only moderate since an equivalent amount of the nitrile oxide is consumed by reaction with the amine released in the fragmentation of the primary cycloadducts and reforms the amidoxime. With excess nitrile oxides the 1,2,4-oxadiazole-4+=kies undergo a dispropotionation reaction to yield nitroso carbnyl intermediates and 1,2,4_oxadiazoles. 0 1997, Elsevier Science Ltd. All rights reserved.
Synthesis of Some 3-Aryl-1,2,4-oxadiazoles Carrying a Protected L-Alanine Side Chain
Journal of the Brazilian Chemical Society, 1998
A síntese de alguns derivados dos 1,2,4-oxadiazóis (4a-d) partindo das arilamidoximas apropriadas (1a-d) e do ácido N-t-butoxycarbonil-O-benzil-L-aspártico é descrita. As estruturas destes novos compostos foram determinadas por meios espectroscópicos. The synthesis of some 1,2,4-oxadiazole derivatives (4a-d) starting from arylamidoximes 1a-d and N-t-butoxycarbonyl-O-benzyl-L-aspartic acid is described. The structures of these new products have been determined by spectroscopic methods.
Synthesis of 2-amino-5-(5R-1,2,4-oxadiazolyl-3)-1,3,4-oxadiazoles
Russian Chemical Bulletin, 1993
The interaction of 2-amino-l,3,4-oxadiazole-5-carboxamidoxime with nitriles in the presence of ZnC12 and HC1 or with trichloroacetic anhydride affords 2-amino-5-(5R-1,2,4oxadiazolyl-3)-l,3,4-oxadiazoles. Their reactions with N-nucleophiles have been studied.
1988
In the I& decade we have been involved in a program directed for developing new approaches for the synthesis of polyf unctionally heterocycles utilising simple and laboratory available starting materials [1-31. During this pha,se of our work we could contribute effort for exploring the synthetic potentialities of trichloroncetonit,rile [4], malononitrile , and hydrazonyl halides [6, 71 in heterocyclic synthesis. I n continuation of this work we report here on the utility of a-ehlorobenzaldoxime (1) in heterocyclic synthesis.
Synthesis and biological activity of 2-(4,5-dihydroisoxazol-5-yl)-1,3,4-oxadiazoles
Bioorganic Medicinal Chemistry Letters, 2009
Acid hydrazides were coupled with acrylic acid derivatives and cyclodehydration gave 1,3,4-oxadiazoles. Lastly, in-situ nitrile oxide formation from aryl oximes treated with sodium hypochlorite, and subsequent 1,3-dipolar cycloaddition to the exomethylene moiety delivered 2-(4,5-dihydroisoxazol-5-yl)-1,3,4-oxadiazoles. This library was evaluated in a high-throughput screen at Dow AgroSciences. Several compounds were active against fungal pathogens and pest insects.
Oxadiazole: Synthesis, characterization and biological activities
Journal of Saudi Chemical Society, 2012
The synthesis of novel achiral and chiral amides incorporating 1,3,4-oxadiazole ring are reported. All the synthesized amides are characterized 1 H, 13 C, FTIR and elemental analysis techniques. Synthesized compounds are screened for microbial and cytotoxic activities.
Synthetic trends followed for the development of 1,3,4-oxadiazole based compounds
IP Innovative Publication Pvt. Ltd., 2017
1,3,4-oxadiazoles, heterocycles bearing one oxygen and two nitrogen atoms in a five membered ring have their application in the diverse areas of medicine. Enough literature is available demonstrating antibacterial, antifungal, anticonvulsant, antiviral, antidiabetic and antimalarial potential of the moiety. Owing to their wide applications, scientists across the globe are engaged in the design and development of oxadiazole derived medicinal agents. This motif can also be traced in a number of drug molecules. Most commonly adopted method for their synthesis includes he reaction between acid hydrazides and acid chorides/carboxylic acids or direct cyclization of diacylhydrazines in the presence of different dehydrating agents like phosphorus oxychloride, thionyl chloride, phosphorus pentaoxide and polyphosphoric acid. This manuscript covers different conventional and non-conventional approaches adopted for the synthesis of 1,3,4-oxadiazole derivatives.