2518-61-8Relevant academic research and scientific papers
IBX/KI promoted synthesis of 2, 5-disubstituted 1, 3, 4-oxadiazoles
Khan, P. Rasvan,Durgaprasad,Reddy, S. Gopal,Reddy, G. Raveendra,Hussein, Ibnelwaleed A.,Reddy, B.V. Subba
, p. 64 - 69 (2018/03/05)
Background: Oxadiazoles are privileged scaffolds in different areas of medicinal, pesticidal, polymer and material science. They act as anticancer, benzodiazepine receptor agonists, antimicrobial, analgesic, diuretic and tyrosinase inhibitors etc. A number of compounds containing an oxadiazole moiety are in late stage clinical trials including zibotentan and furamizole. Despite numerous methods are reported, the majority of them suffer from major drawbacks such as the use of strong alkaline or acidic conditions, highly toxic and corrosive reagents and also involve the use of costly reagents, elevated temperatures and longer reaction times. Inspired by the potential application of hypervalent iodonium reagents in organic synthesis, we would like to explore the readily available IBX and KI reagents for the facile synthesis of 1, 3, 4-oxadiazoles. Method: Oxidative cyclization has successfully been developed for the synthesis of 2, 5-disubstituted 1, 3, 4-oxadiazoles. Results: An efficient process for the one-pot synthesis of 2, 5-disubstituted 1, 3, 4-oxadiazoles has been developed using IBX/KI system at 25°C. The reaction was successful with a wide range of substrates such as aromatic and heterocyclic aldehyde and arylhydrazides to afford the corresponding unsymmetrical 2, 5-disubstituted 1, 3, 4-oxadiazoles. The mild reaction conditions, cost-effective reagents and short reaction time are noteworthy advantages of this methodology. Conclusion: We have developed a one-pot strategy for the synthesis of 1, 3, 4-oxadiazioles using a combination of IBX/KI at ambient temperature. This one-pot procedure proved to be quite general and worked well with a wide variety of aryl and heterocyclic aldehydes and variety of acylhydrazides. The advantage of this method lies in the simplicity of experimental procedure and the ready accessibility of the reagents, which render this, an experimentally attractive method for the preparation of unsymmetrical 1, 3, 4-oxadiazoles.
Microwave-mediated Green synthesis of oxadiazole derivatives against inflammatory disease
Sahoo, Biswa Mohan,Panda, Jnyanaranjan,Banik, Bimal Krishna,Sahoo, Binayani
, p. 1307 - 1310 (2020/06/27)
A rapid and efficient microwave-mediated Green synthesis of oxadiazole derivatives (2a-e) is described based on reaction between benzohydrazide and various substituted benzoic acids. The use of microwave irradiation to carry out chemical reactions provide
Structure activity relationships, multidrug resistance reversal and selectivity of heteroarylphenyl ABCG2 inhibitors
K?hler, Sebastian C.,Vahdati, Sahel,Scholz, Matthias S.,Wiese, Michael
, p. 483 - 500 (2018/02/14)
An overexpression of the transmembrane ATP-binding cassette transporter G2 (ABCG2, BCRP) in cancer tissues is supposed to play a role in the multidrug resistance (MDR) of tumors resulting in an inefficient chemotherapy. Therefore, co-administration of sel
2,5-Diaryloxadiazoles and their precursors as novel inhibitors of cathepsins B, H and L
Garg, Shweta,Raghav, Neera
, p. 64 - 74 (2016/07/06)
High levels of cathepsins indicated in various pathological conditions like arthritis, cancer progressions, and atherosclerosis explains the need to explore potential inhibitors of these proteases which can be of great therapeutic significance. We, in the present work, report the synthesis of some 2,5-diaryloxadiazoles from N-subsitutedbenzylidenebenzohydrazides. The synthesized compounds were screened for their inhibitory potential on cathepsins B, H and L. Structure Activity Relationship studies show that 2,5-diaryloxadiazoles were less inhibitory than their precursors. 1i and 2k have been found to be most inhibitory to cathepsins B and L. Their Ki values have been calculated as 11.38 × 10-8 M and 66.4 × 10-8 M for cathepsin B and 4.2 × 10-9 M and 47.31 × 10-9 M for cathepsin L, respectively. However, cathepsin H activity was maximally inhibited by compounds, 1e and 2c with Ki values of 4.4 × 10-7 M and 5.6 × 10-7 M, respectively. Enzyme kinetic studies suggest that these compounds are competitive inhibitors to the enzymes. The results have been compared with docking results obtained using iGemDock.
METHOD FOR PREPAREING 1,3,4-OXADIAZOL UNDER SOLVENT-FREE CONDITION
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Paragraph 0074-0079; 0112-0113; 0127-0128, (2017/02/24)
The present invention relates to a synthesis method of 1,3,4-oxadiazol, comprising: 1) under a solvent-free condition and by means of a mechanical pulverization method, making a hydrazide compound react with an aldehyde compound and thereby synthesizing a N-acylhydrazone compound; and 2) under a solvent-free condition, adding an iodine-based oxidizing agent to the N-acylhydrazone compound to synthesize 1,3,4-oxadiazol via oxidative cyclization. The solventless synthesis method of 1,3,4-oxadiazol according to the present invention is easy to perform and handle, and has the advantage of synthesizing 1,3,4-oxadiazol at high selectivity and yield. Also, the solventless synthesis method of the present invention can prevent the formation of side products caused by the minute amount of water that usually remains in solvents, and can further prevent synthesized intermediates from being converted back into the starting materials by the water.COPYRIGHT KIPO 2016
Efficient synthesis of 1,3,4-oxadiazoles promoted by NH4Cl
Gnanasekaran, Krishna Kumar,Nammalwar, Baskar,Murie, Maeghan,Bunce, Richard A.
supporting information, p. 6776 - 6778 (2015/01/09)
An efficient and inexpensive approach to the synthesis of 2-substituted and 2,5-disubstituted 1,3,4-oxadiazoles from arylhydrazides and orthoesters is reported using catalytic NH4Cl. The conditions are mild, and thus, compatible with a variety of functional groups. The optimized reaction is performed using 30 mol % of NH4Cl in 100% EtOH and is generally complete within 1 h for non-aromatic orthoesters and 2-10 h for aromatic orthoesters. The reaction permits both electron-releasing and electron-withdrawing groups on the arylhydrazide substrate. Most products are formed in high yields and require only minimal purification. Compared with earlier reports, the current reactions proceed in shorter time and require less of the orthoester.
SYNTHESIS OF 2,5-DISUBSTITUTED 1,3,4-OXADIAZOLES FROM TRICHLOROMETHYLARENES AND ACYLHYDRAZINES
Poddubnyi, I. S.,Belen'skii, L. I.,Krayushkin, M. M.
, p. 602 - 607 (2007/10/02)
A preparative synthesis of 2,5-disubtituted 1,3,4-oxadiazoles by the reaction of trichloromethylarenes with hydrazides of carboxylic acids of the aliphatic, aromatic and heteroaromatic series in methanol or ethanol in the presence of pyridine was developed.
Triethyl phosphite mediated synthesis of indazoloquinazolinoperimidines, oxadiazoloindazoles and thiadiazoloindazoles
Reddy, V Rama Kishan,Reddy, P S N,Ratnam, C V
, p. 499 - 502 (2007/10/02)
2-(2-Aminophenyl)perimidine (1) on treatment with 2-nitrobenzaldehydes (2) in acetic acid gives 5,6-dihydro-6-(2-nitroaryl)quinazolinoperimidines (4) which on permanganate oxidation yield 6-(2-nitroaryl)quinazolinoperimidines (5). 5-on triethylphosphite (TEP) mediated deoxygenative cyclisation afford indazoloquinazolinoperimidines (6).Similarly, 5-aryl-2-(2-nitrophenyl)oxadiazoles (9) and 2-arylamino-5-(2-nitrophenyl)thiadiazoles (14) on treatment with TEP give 2-aryloxadiazoloindazoles (10) and2-(N-ethylarylamino)thiadiazoloindazoles (16) respectively.
Oxydations d'hydrazones par le bioxyde de plomb: nouvelles syntheses d'oxadiazoles-1,3,4 et de derives de l'amino-4 triazol-1,2,4 one-5
Milcent, Rene,Barbier, Geo
, p. 77 - 80 (2007/10/02)
Aromatic aldehyde aroylhydrazones when oxidized with lead dioxide, in acetic acid, gave quickly the corresponding 1,3,4-oxadiazoles in good yields.Aromatic aldehyde carbodihydrazones on the other hand, gave derivatives of 4-amino-3-aryl-1,2,4-triazol-5-ones, in dimethylformamide as solvent.To explain these results, some radical mechanisms are proposed.
