- Investigation of Masked N-Acyl-N-isocyanates: Support for Oxadiazolones as Blocked N-Isocyanate Precursors
-
In contrast to carbon-substituted isocyanates that are common building blocks, N-substituted isocyanates remain underdeveloped and reports on their N-acyl derivatives (i. e. amido-isocyanates) are exceedingly rare. Herein, amido-isocyanates were investiga
- Gagné-Monfette, William,Vincent-Rocan, Jean-Fran?ois,Lutes, Owen C.,O'Keefe, Geneviève F.,Jeanneret, Alexandria D. M.,Blanger, Claire,Ivanovich, Ryan A.,Beauchemin, André M.
-
supporting information
p. 14051 - 14056
(2021/09/14)
-
- Copper-Catalyzed Selective N-Arylation of Oxadiazolones by Diaryliodonium Salts
-
Here, we report the method for copper-catalyzed N-arylation of diverse oxadiazolones by diaryliodonium salts under mild conditions in high yields (up to 92%) using available CuI as a catalyst. The developed method allows utilizing both symmetric and unsymmetric diaryliodonium salts bearing auxiliary groups such as 2,4,6-trimethoxyphenyl (TMP). We found that the steric effects in aryl moieties determined the chemoselectivity of N- and O-arylation of the 1,2,4-oxadiazol-5(4H)-ones. Mesityl-substituted diaryliodonium salts demonstrated the high potential as a selective arylation reagent. The structural study suggests that steric accessibility of N-atom in 1,2,4-oxadiazol-5(4H)-ones impact to arylation with sterically hindered diaryliodonium salts. The synthetic application of proposed method was also demonstrated on selective arylation of 1,3,4-oxadiazol-2(3H)-ones and 1,2,4-oxadiazole-5-thiol. (Figure presented.).
- Soldatova, Natalia S.,Semenov, Artem V.,Geyl, Kirill K.,Baykov, Sergey V.,Shetnev, Anton A.,Konstantinova, Anna S.,Korsakov, Mikhail M.,Yusubov, Mekhman S.,Postnikov, Pavel S.
-
supporting information
p. 3566 - 3576
(2021/06/16)
-
- DMF as Methine Source: Copper-Catalyzed Direct Annulation of Hydrazides to 1,3,4-Oxadiazoles
-
An unprecedented Cu-catalyzed direct annulation of hydrazides with N,N-dimethylformamide (DMF) was developed, providing an efficient synthesis of valuable 1,3,4-oxadiazoles. This process features the short reaction time and can be safely conducted on gram scale. The reaction also facilitated the convenient synthesis of 1,3,4-oxadiazole-2(3H)-ones. Moreover, the mechanistic studies suggest that the source of CH is from the N-methyl group of DMF. (Figure presented.).
- Wang, Shoucai,Wang, Kai,Kong, Xiangfei,Zhang, Shuhua,Jiang, Guangbin,Ji, Fanghua
-
p. 3986 - 3990
(2019/07/31)
-
- Synthesis and In Vitro Anticancer Activity of Novel 1,3,4-Oxadiazole-Linked 1,2,3-Triazole/Isoxazole Hybrids
-
A series of new 1,3,4-oxadiazole-linked 1,2,3-triazole/isoxazole derivatives were designed and synthesized. All the synthesized compounds were screened for in vitro anticancer activity against four human cancer cells: HeLa (cervical), MDA-MB-231 (breast), DU-145 (prostate), and HEPG2 (liver). Among 17 compounds tested, 7a, 7c, and 7d showed potent activity toward four cell lines.
- Madhavilatha,Bhattacharjee, Debanjan,Sabitha, Gowravaram,Reddy, B. V. Subba,Yadav,Jain, Nishant,Reddy, B. Jagan Mohan
-
p. 863 - 870
(2018/02/12)
-
- Application of N-Acylbenzotriazoles in the Synthesis of 5-Substituted 2-Ethoxy-1,3,4-oxadiazoles as Building Blocks toward 3,5-Disubstituted 1,3,4-Oxadiazol-2(3H)-ones
-
5-Substituted-2-ethoxy-1,3,4-oxadiazoles were conveniently prepared through a one-pot sequential N-acylation/dehydrative cyclization between ethyl carbazate and N-acylbenzotriazoles in the presence of Ph3P-I2 as a dehydrating agent. Subsequent treatment with a stoichiometric amount of alkyl halides (X = Cl, Br, I) enables a rapid access to a variety of 3,5-disubstituted 1,3,4-oxadiazol-2(3H)-ones in good to excellent yields.
- Wet-Osot, Sirawit,Phakhodee, Wong,Pattarawarapan, Mookda
-
p. 9923 - 9929
(2017/09/23)
-
- Computer-assisted design, synthesis, binding and cytotoxicity assessments of new 1-(4-(aryl(methyl)amino)butyl)-heterocyclic sigma 1 ligands
-
In this work we applied a blend of computational and synthetic techniques with the aim to design, synthesize, and characterize new σ1 receptor (σ1R) ligands. Starting from the structure of previously reported, high-affinity benzoxazolone-based σ1 ligands, the three-dimensional homology model of the σ1R was exploited for retrieving the molecular determinants to fulfill the optimal pharmacophore requirements. Accordingly, the benzoxazolone moiety was replaced by other heterocyclic scaffolds, the relevant conformational space in the σ1R binding cavity was explored, and the effect on σ1R binding affinity was ultimately assessed. Next, the compounds designed in silico were synthesized, and their affinity and selectivity toward σ1and σ2receptors were tested. Finally, a representative series of best σ1R binders were assayed for cytotoxic activity on the SH-SY5Y human neuroblastoma cell line. Specifically, the new 4-phenyloxazolidin-2-one derivatives 2b (i.e., (R)-2b and (S)-2b) emerged as potential leads for further development as σ1R agents, as they were found endowed with the highest σ1R affinity (Kiσ1 values in the range 0.95–9.3?nM), and showed minimal cytotoxic levels exhibited in the selected, cell-based test, in line with a σ1R agonist behavior.
- Zampieri, Daniele,Vio, Luciano,Fermeglia, Maurizio,Pricl, Sabrina,Wünsch, Bernhard,Schepmann, Dirk,Romano, Maurizio,Mamolo, Maria Grazia,Laurini, Erik
-
p. 712 - 726
(2016/07/06)
-
- Synthesis of 5-substituted-3H-[1,3,4]-oxadiazol-2-one derivatives: A carbon dioxide route (CDR)
-
A carbon dioxide route (CDR) for making biologically important 5-substituted-3H-[1,3,4]-oxadiazol-2-ones (SHOs) has been accomplished through synthesis and cyclization of a variety of hydrazides as the key intermediates. All of these hydrazides were prepared readily in 89-97% yields by reacting acid chlorides with a hydrazine monohydrate in the initial step. Then, SHOs were obtained in high yields from hydrazides by reacting them with carbon dioxide under basic conditions. More notable than the high yields, is that the present CDR process for the first time has succeeded in providing a straightforward cyclization reaction leading to SHO formation with simple reagents in ethanol solution.
- Brahmayya,Dai, Shenghong A.,Suen
-
p. 65351 - 65357
(2015/08/18)
-
- Highly chemo- and regioselective allylic substitution with tautomerizable heteroarenes
-
Tautomerizable heteroarenes, bearing multiple interconvertible nucleophilic centers exhibit high chemo- and regioselective allylation irrespective of allylating agents used under Pd-catalysis. The achieved selectivity may be attributed to the dominant lactam form of heteroarenes and Pd-catalyzed intramolecular allylic substitution. A generalized green protocol for chemo- and regioselective allylation of biologically relevant heteroarenes with allyl alcohols in dimethyl carbonate (DMC) as solvent was developed. Excellent selectivity was observed during intermolecular competition study demonstrating the differential nucleophilicity of tautomerizable heteroarenes and differential allyl palladium forming ability of a variety of allyl alcohols.
- Kumar, Dinesh,Vemula, Sandeep R.,Cook, Gregory R.
-
supporting information
p. 4300 - 4306
(2015/08/11)
-
- Palladium-catalyzed oxidative O-H/N-H carbonylation of hydrazides: Access to substituted 1,3,4-oxadiazole-2(3 H)-ones
-
A novel palladium-catalyzed oxidative annulation reaction for the C-O, C-N bond formations is developed. The intramolecular cyclocarbonylation provides an efficient and direct approach for the construction of valuable 1,3,4-oxadiazole-2(3H)-ones and their
- Ji, Fanghua,Li, Xianwei,Guo, Wei,Wu, Wanqing,Jiang, Huanfeng
-
p. 5713 - 5718
(2015/06/16)
-
- Transition-metal-free oxidative iodination of 1,3,4-oxadiazoles
-
Transition-metal-free oxidative iodination of 2-substituted 1,3,4-oxadiazoles was achieved by using sodium iodide as the halide source and Selectfluor as the oxidant. Variously substituted products were obtained in moderate to good yields under operationa
- Dannenberg, Carl Albrecht,Bizet, Vincent,Zou, Liang-Hua,Bolm, Carsten
-
supporting information
p. 77 - 80
(2015/02/02)
-
- Microwave assisted synthesis of 1,3,4-oxadiazole/thiohydantoin hybrid derivatives via dehydrative cycliztion of semicarbazide
-
A series of compounds containing both 1,3,4-oxadiazole and thiohydantoin were synthesized as a promising scaffold for application in medicinal chemistry. The key step of the synthesis is a microwave-assisted cyclization of semicarbazides possessing a thiohydantoin moiety at one of the acyl termini using POCl3 as a dehydrating reagent. A wide range of semicarbazides were prepared through the substitution of hydrazides with an N-acylated thiohydantoin derived from the cyclization of the corresponding isothiocyanate with an amino acid and subsequent N-acylation of the resultant thiohydrantion. Consequently, the 58 number of 1,3,4-oxadiazole derivatives having a thiohydantoin substituent were prepared in good overall yields. Thiohydantoin 134-Oxadiazole Semicarbazide Microwave Amino acid Acknowledgments. This research was conducted under the Industrial Infrastructure Program for Fundamental Technologies and Institute for Advancement of Technology through the Inter-ER Cooperation Projects (R0002016) which are funded by the Ministry of Trade, Industry & Energy, Korea to YDG and Open Translational Research Center for Innovative Drug (2012M3A9C1053532) which are funded by National Research Foundation of Korea.
- Yang, Seung-Ju,Lee, Jae-Min,Lee, Gee-Hyung,Kim, NaYeon,Kim, Yong-Sang,Gong, Young-Dae
-
p. 3609 - 3617
(2015/02/05)
-
- The use of a Mitsunobu reagent for the formation of heterocycles: A simple method for the preparation of 3-alkyl-5-aryl-1,3,4-oxadiazol-2(3H)-ones from carboxylic acids
-
The reaction of carboxylic acids with Mitsunobu reagents, prepared by the reaction of triphenylphosphine with dialkyl azodicarboxylates, followed by heating at 180-190 °C under solvent-free conditions, afforded 3-alkyl-5-aryl-1,3,4-oxadiazol-2(3H)-ones. This facile and convenient method readily provides the 1,3,4-oxadiazolone ring systems in good yields using a one-pot protocol starting from the corresponding carboxylic acids. It was also demonstrated that the presence of a catalytic base facilitates the final ring closure forming the 1,3,4-oxadiazol-2(3H)-one.
- Sugimoto, Osamu,Arakaki, Tomoyo,Kamio, Hiroka,Tanji, Ken-Ichi
-
supporting information
p. 7314 - 7317
(2014/07/07)
-
- Synthesis of 5-aryl-3H-[1,3,4]oxadiazol-2-ones from N′-(chloro-aryl- methylene)-tert-butylcarbazates using basic alumina as an efficient and recyclable surface under solvent-free condition
-
The synthesis of biologically important 5-aryl-3H-[1,3,4]oxadiazol-2-ones has been carried out by heating the easily synthesized N′-(chloro-aryl- methylene)-tert-butylcarbazates on basic alumina surface under solvent-free condition. The dual characteristic of basic alumina as a solid support as well as a nucleophile is successfully exploited in these reactions. The method provides special attributions such as reduced reaction times, easier work-up procedures, and good to excellent yields as well as increased purity of products and most importantly environmentally friendly protocols. The basic alumina is easily recovered and utilized for further reactions several times without serious loss of activity.
- Debnath, Kamalesh,Pathak, Sudipta,Pramanik, Animesh
-
p. 896 - 899
(2013/02/25)
-
- Propylene oxide assisted one-pot, tandem synthesis of substituted-1,3,4- oxadiazole-2(3H)-ones in water
-
It has been developed for the synthesis of substituted-1,3,4-oxadiazole- 2(3H)-one derivatives via a novel one-pot, tandem procedure assisted by propylene oxide. The 5-substitued-1,3,4-oxadiazole-2(3H)-ones and 3,5-disubstitued-1,3,4-oxadiazole-2(3H)-ones were, respectively, obtained from three-component reaction of acylhydrazines, carbon disulfide, and propylene oxide, and four-component reaction of acylhydarazines, carbon disulfide, propylene oxide, and organic halides. The reactions were carried out using water as solvent in the presence of potassium phosphate to afford the expected products in good to excellent yields.
- Yan, Xu,Zhou, Shuo,Wang, Yuanqiang,Ge, Zemei,Cheng, Tieming,Li, Runtao
-
experimental part
p. 7978 - 7983
(2012/09/21)
-
- Room-temperature copper-catalyzed oxidation of electron-deficient arenes and heteroarenes using air
-
No pressure: The oxidation of aromatic C-H bonds at room temperature was realized through a copper-catalyzed "oxygenase-type" oxidation of arenes and heteroarenes in the presence of air (see scheme). The reaction involves an oxygen-atom transfer from O2 in the air onto the substrates. Copyright
- Liu, Qiang,Wu, Pan,Yang, Yuhong,Zeng, Ziqi,Liu, Jie,Yi, Hong,Lei, Aiwen
-
supporting information; experimental part
p. 4666 - 4670
(2012/06/30)
-
- Antimycobacterial activity of new 3,5-disubstituted 1,3,4-oxadiazol-2(3H)-one derivatives. Molecular modeling investigations
-
3H-1,3,4-Oxadiazol-2-one derivatives were synthesized and tested for their in vitro antimycobacterial activity. Oxadiazolone derivatives showed an interesting antimycobacterial activity against the reference strain of Mycobacterium tuberculosis H37Rv. Molecular modeling investigations were performed and showed that the active compounds possess all necessary features to target the protein active site of the mycobacterial cytochrome P450-dependent sterol 14α-demethylase in the sterol biosynthesis pathway as the calculated free energy of binding were in agreement with the corresponding MIC values.
- Zampieri, Daniele,Mamolo, Maria Grazia,Laurini, Erik,Fermeglia, Maurizio,Posocco, Paola,Pricl, Sabrina,Banfi, Elena,Scialino, Giuditta,Vio, Luciano
-
experimental part
p. 4693 - 4707
(2009/10/24)
-
- Efficient phosphonium-mediated synthesis of 2-amino-1,3,4-oxadiazoles
-
We present an efficient, room temperature procedure for the preparation of 2-amino-1,3,4-oxadiazoles. Oxadiazol-2-ones can be activated for SnAr substitution using phosphonium reagents (e.g., BOP). This approach provides convenient access to N,
- Levins, Christopher G.,Wan, Zhao-Kui
-
supporting information; experimental part
p. 1755 - 1758
(2009/04/12)
-
- 1-Thia-3,4-diazolidine-2,5-dione Functionality: A Photochemical Synthon for the Azo Group
-
The 1-thia-3,4-diazolidine-2,5-dione functional group was shown to yield azo compounds upon photolysis.This photoreaction when combined with the known ability of this group to react in a Diels-Alder fashion or as a dinucleophile toward alkylating agents greatly increases the utility of this functionality.The dual reactivity of this group was demonstrated in the synthesis of a number of 3,4-dialkyl-1-thia-3,4-diazolodone-2,5-diones.The photolysis of these compounds produced either thermally stable cyclic azo compounds or the decomposition products of thermally unstable azo compounds.
- Squillacote, Michael,Felippis, James De
-
p. 3564 - 3571
(2007/10/02)
-
- Syntheses and thermal rearrangements of 2-phenyl-4-alkoxycarbonyl-1,3,4-oxadiazol-5(4H)-ones and related sulfur compounds
-
Syntheses of nine 2-phenyl-4-alkoxycarbonyl-1,3,4-oxadiazol-5(4H)-ones are described.On heating about 200 deg C, these compounds decarboxylate and give 2-phenyl-4-alkyl-1,3,4-oxadiazol-5(4H)-ones.Although many analogies suggest that the rearrangement proceeds through the cyclisation of a 1,5-dipole, arising from the decarboxylation of the heterocycle, no direct evidence for such a mechanism was obtained.On the contrary, the synthesis and the thermal rearrangement of four related sulfur compounds show that such a postulated intermediate cannot explain all the experimental results.
- Golfier, M.,Guillerez, M. G.
-
-
- Synthesis of 5-Aryl-3-carbazoyl-1,3,4-oxadiazol-2(3H)-one. Derivatives and their Ring Transformation into 5-Benzamido-1,2,4-triazolidine-3,5-dione Derivatives
-
Some 5-aryl-3-carbazoyl-1,3,4-oxadiazol-2(3H)-one derivatives 6 and 9 have been synthesized in two ways.The expected thermal ring transformation into 2,5-disubstituted 1,3,4-oxadiazoles did not occur but, by acid hydrolysis of 5-aryl-3-3-benzylidene-2-me
- Milcent, Rene,Barbier, Geo,Tzirenstchikow, Tatiana,Lebreton, Luc
-
p. 231 - 236
(2007/10/02)
-
- Heterocyclic Photorearrangements. Photochemical Behaviour of Some 3,5-Disubstituted 1,2,4-Oxadiazoles in Methanol at 254 nm
-
Photochemical behaviour of some 3,5-disubstituted 1,2,4-oxadiazoles in methanol at 254 nm has been investigated.Ring photoisomerization to the 1,3,4-oxadiazole heterocycle or formation of open chain compounds involving the nucleophilic solvent was shown to depend on the nature and the position of the substituent.Photoinduced ring closure into the benzimidazole system, involving a 3-N-phenylamino side chain sequence and a photolytic intermediate of the oxadiazole heterocycle, is also reported.
- Buscemi, Silvestre,Cicero, Maria G.,Vivona, Nicolo,Caronna, Tullio
-
p. 931 - 935
(2007/10/02)
-
- Some 1-Aroyl-4,4-dialkylsemicarbazides and Their Cyclization to Afford 5-Aryl-1,3,4-oxadiazol-2(3H)-ones
-
Some 1-aroyl-4,4-dialkylsemicarbazides have been prepared by reacting aroyl-hydrazides with dimethyl- or diethyl-carbamoyl chloride.In boiling DMF they lose dimethylamine or diethylamine to give 5-aryl-1,3,4-oxadiazol-2(3H)-ones. - Keywords: 1-Aroyl-4,4-d
- Davidson, John S.
-
p. 1027 - 1030
(2007/10/02)
-
- 1,3,4-Oxadiazolin-2-ones from Carbo-t-butoxyhydrazones
-
5-Substituted-1,3,4-oxadiazolin-2-ones 2 were synthesized by the oxidation of carbo-t-butoxyhydrazones 1 of aromatic aldehydes with lead tetraacetate or, preferably, iodosobenzene diacetate.In some instances 5-acetoxy-1,3,4-oxadiazoles 3 were obtained along with 2.The oxidation of carboethoxyhydrazones 4 gave 2-ethoxy-1,3,4-oxadiazoles 5.
- Baumgarten, Henry E.,Hwang, Deng-Ruey,Rao, T. N.
-
p. 945 - 949
(2007/10/02)
-
- Fungicidal 5-oxo-4-trisubstituted tin-1,3,4-oxadiazolines
-
Compounds of the formula: STR1 wherein R is aryl of 6 to 10 carbon atoms; substituted aryl substituted with 1 to 5 substituents selected from halogen, nitro, lower alkyl of 1 to 6 carbon atoms, lower alkoxy of 1 to 6 carbon atoms, lower alkylthio of 1 to
- -
-
-
- Synthesis of Some New 5-Aryl/Aryloxymethyl-2-Chloro-1,3,4-Oxadiazoles and their Oxadiazoloquinazolone Derivatives as Potential Pesticides
-
Several 5-aryl/aryloxymethyl-2-chloro-1,3,4-oxadiazoles (III) have been prepared by treating 2-aryl/aryloxymethyl-Δ2-1,3,4-oxadizolin-5-ones (IIa) with POCl3/PCl5.The latter were prepared by cyclisation of their corresponding N-aroylaryloxyacet
- Singh, H.,Yadav, L. D. S.,Bhattacharya, B. K.
-
p. 436 - 439
(2007/10/02)
-
- 1,3,4-Oxadiazol-2(3H)-one Formation from N-Acylaminobiurets and Related Compounds and from S-Benzyl 3-Acyl(thiocarbazates)
-
The formation of 1,3,4-oxadiazol-2(3H)-ones by thermal cyclisation of 1-acylsemicarbazides has been shown to occur with equal facility by use of readily available N-acylaminobiurets.Cyclisation by thermolysis of S-benzyl-3-acylcarbazates also proceeds smoothly in lower yields.
- Bentley, Kenneth W.,Burton, Michael,Uff, Barrie C.
-
p. 2019 - 2022
(2007/10/02)
-
- Synthesis of Substituted N-(2,4-Dioxo-1,2,3,4-tetrahydroquinazolinyl)benzamides and N-(2-Thiono-4-oxo-1,2,3,4-tetrahydroquinazolinyl)benzamides
-
Substuted N-(2,3-dioxo-1,2,3,4-tetrahydroquinazolinyl)benzamides (3a-g) and substituted N-(2-thiono-4-oxo-1,2,3,4-tetrahydroquinazolinyl)benzamides (4a-g) were synthetized in one step from the reaction of methyl anthranilate with 2-aryl-1,3,4-oxadiazolin-5-ones (1a-g) and 2-aryl-1,3,4-oxadiazoline-5-thiones (2a-g), respectively, in m-cresol at 150-160 deg C.Alternative routes leading to the formation of 3a and 4a are also reported.
- Chau, Nguyen,Saegusa, Yasuo,Iwakura, Yoshio
-
p. 541 - 544
(2007/10/02)
-