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1.
Abdel‐Sattar S. Hamad Elgazwy Mayssoune Y. Zaki Nahed N. Eid Ahmed I. Hashem 《Heteroatom Chemistry》2003,14(6):570-574
A series of 2‐phenyl‐5‐alkenyl‐1,3,4‐oxadiazoles were synthesized in high yields from the corresponding dicarbonylhydrazides through cyclodehydration. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:570–574, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10197 相似文献
2.
New 5′‐acetyl‐3′‐1,3,4‐thiadiazoliminothymidines 11, 14 were prepared, via spontaneous rearrangments, by cycloaddition of 5′‐acetyl‐3′‐deoxy‐3′‐isothiocyanatothymidine 9 with 1‐aza‐2‐azoniaallene hexachloantimonates. Similary, 3′‐cyano analogue 19 was reacted with the same cumulenes to furnish 3′‐1,2,4‐triazolo‐thymidines 22, 24 , and 26 . Deblocking of the acylated products afforded the free nucleosides. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:298–303, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10146 相似文献
3.
An efficient soluble poly(ethylene glycol) (PEG) supported liquid‐phase parallel synthetic method for 2,5‐disubstituted 1,3,4‐oxadiazoles and 1,3,4‐thiadiazoles is described. 2‐Aryl‐5‐(4′‐methoxycarbonylphenoxymethyl)‐1,3,4‐oxadiazoles and 2‐aryloxymethyl‐5‐(4′‐methoxycarbonylphenoxyacetamido)‐1,3,4‐thiadiazoles are synthesized in high yield and high purity using this polymer supported strategy. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:664–669, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20253 相似文献
4.
New electroluminescent materials of 1,3,4‐oxadiazole–1,2,3‐triazole and 1,3,4‐oxadiazole–1,2,3‐triazole–pyridine hybrid derivatives were synthesized and characterized. Following spectroscopic studies and characterization of their electronic properties, 1,3,4‐oxadiazole–1,2,3‐triazole hybrids and 1,3,4‐oxadiazole–1,2,3‐triazole–pyridine derivatives were found to be potentially efficient blue electroluminescent materials. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:322–328, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20210 相似文献
5.
Oleksandr V. Golovchenko Stepan G. Pilyo Vladimir S. Brovarets Alexander N. Chernega Boris S. Drach 《Heteroatom Chemistry》2004,15(6):454-458
Available 2‐acylamino‐3,3‐dichloroacrylonitriles, when treated with hydrazine hydrate, provide 2‐alkyl‐ or 2‐aryl‐5‐hydrazino‐1,3‐oxazole‐4‐carbonitriles that readily add alkyl or aryl isothiocyanates and the adducts formed recyclize on heating. Finally, the synthesis results in 5‐alkyl(aryl)amino‐1,3,4‐thiadiazol‐2‐yl(acylamino)acetonitriles or the products of their further cyclization, 2‐(5‐amino‐1,3‐ oxazol‐2‐yl)‐1,3,4‐thiadiazole derivatives. The structures of the novel substituted 1,3,4‐thiadiazoles are corroborated spectroscopically as well as by X‐ray diffraction method. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:454–458, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20041 相似文献
6.
Treatment of 3‐(3‐methylbenzofuran‐2‐yl)‐3‐oxopropanenitrile ( 1 ) with phenyl isothiocyanate afforded the thioacetanilide derivative 3 , which when reacted with α‐haloketones, α‐halodiketones, and hydrazonoyl chlorides gives thiophene, 1,3‐oxathiole, and 1,3,4‐thiadiazole derivatives 6a,b, 10a,b and 14a–g , respectively. Treatment of 3‐methyl‐2‐benzofurancarboxylic acid hydrazide ( 15 ) with benzaldehyde followed by bromine afforded the 1,3,4‐oxadiazole derivative 18 . Treatment of the acid hydrazide 15 with phenyl isothiocyanate gave the thiosemicarbazide 20 . Compound 20 could be converted into 1,3,4‐oxadiazole, 1,2,4‐triazole‐3‐thione, and 1,3,4‐thiadiazole derivatives 21, 22 , and 23 , respectively. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:294–300, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20298 相似文献
7.
Ming‐Hsiang Shin Fung Fuh Wong Chun‐Min Lin Wen‐Yi Chen Mou‐Yung Yeh 《Heteroatom Chemistry》2006,17(2):160-165
New potential bluish‐green electroluminescent materials of 1,3,4‐oxadiazole–triazolopyridin‐ one–carbazole derivatives were synthesized and characterized for single‐layer devices. Carbazole, pyridine, and triazolopyridinone were completely introduced into 1,3,4‐oxadiazole skeletal to play assistant roles in controlling fundamental photolytic process due to the electron‐donating nature, excellent photoconductivity, and flexible structure properties. Following the spectroscopic studies and the measurements of cyclic voltammogram, 1,3,4‐oxadiazole–triazolopyridinone–carbazole derivatives were highly efficient bluish‐green electroluminescent materials. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:160–165, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20201 相似文献
8.
A simple and efficient method was developed for the synthesis of 1‐(substituted)‐3‐(5‐(substituted)‐1,3,4‐thiadiazol‐2‐yl) ureas from heterocyclic amino compounds and phenyl‐5‐(pyridine‐3‐yl)‐1,3,4‐thiadiazol‐2‐ylcarbamate( 2 ) or phenyl‐5‐(trifluoro‐methyl)‐1,3,4‐thiadiazol‐2‐ylcarbamate( 5 ) under solvent conditions using microwave irradiation. The products were obtained in satisfactory yield as we expected. The reactions can be realized by conventional heating, but we find that the condition of microwave is better according to the reaction time. New 1‐(substituted)‐3‐(5‐(substituted)‐1,3,4‐thiadiazol‐2‐yl) urea derivatives are reported. The products were characterized by 1H NMR, ESI‐MS, and Elemental analysis. The crystal structure of compound 6h was determined by X‐ray single crystal diffraction. © 2008 Wiley Periodicals, Inc. Heteroatom Chem 19:621–629, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20489 相似文献
9.
Alaa A. Hassan Kamal M. El‐Shaieb Raafat M. Shaker Dietrich Dpp 《Heteroatom Chemistry》2005,16(1):12-19
1,4‐Disubstituted thiosemicarbazides 1b–f reacted with ethenetetracarbonitrile ( 5 ) in di‐ methylformamide with formation of 2‐substituted 5‐phenyl‐1,3,4‐thiadiazoles 2a–f and 2‐substituted 5‐phenyl‐1,3,4‐oxadiazoles 4a–f . Upon addition of 5 to 1c–e in chlorobenzene, 3‐amino‐2‐benzoyl‐4,5,5‐tri‐ cyano‐2,5‐dihydro‐1H‐pyrazole‐1‐[N‐(4‐tricyanovi‐nyl)phenyl]carbothioamide ( 12 ), 5‐benzylamino‐, and 5‐allylamino‐4‐benzoyl‐2,3‐dihydro‐[1,3,4]thiadiazol‐ 2,2‐dicarbonitrile ( 13a,b ) and 5‐amino‐1‐benzoylpyrazole‐3,4‐dicarbonitrile ( 14 ) as well as 2‐phenyl‐ 4H‐[1,3,4]‐oxadiazine‐5,6‐dicarbonitrile ( 15 ) were formed. Rationales for the role of the solvent and the conversions observed are presented. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:12–19, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20071 相似文献
10.
Hung‐Te Chang Kuo‐Chen Chiang Fung Fuh Wong Chun‐Sheng Huang Yang‐Ming Liao Wen‐Fa Kuo Shaw‐Bing Won Mou‐Yung Yeh 《Heteroatom Chemistry》2007,18(4):438-442
The synthesis of potential fluorescent active 4‐(5‐aryl‐1,3,4‐oxadiazol‐2‐yl)phenylhydrazine derivatives was accomplished in three steps. The key step was the dehydration cyclization of 1,2‐diacylhydrazines to form the 1,3,4‐oxadiazole ring by use of acetic anhydride/perchloric acid mixture as the dehydrating agent. The sydnone moiety served as the masked hydrazines, which could be demasked by HCl for further application. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:438–442, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20318 相似文献
11.
3‐Methyl‐2‐benzofurancarboxylic acid hydrazide ( 2 ) reacts with carbon disulfide and pota‐ ssium hydroxide to give the corresponding potassium carbodithioate salt 3 . Treatment of the latter salt with hydrochloric acid, hydrazine hydrate, and with phen‐ acyl bromide afforded the corresponding 1,3,4‐oxadia‐ zole‐5‐thione 4 , 4‐amino‐1,2,4‐triazole‐5‐thione 5 , and thiazolidine‐2‐thione 9 derivatives, respectively. The reaction of either 1,3,4‐oxadiazole‐5‐thione 4 or 4‐amino‐1,2,4‐triazole‐5‐thione 5 with phenacyl bromide resulted in the formation of 1,2,4‐triazolo[3, 4‐b]‐1,3,4‐thiadiazine derivative 8 . Treatment of compounds 3 or 4 with hydrazonoyl halides 10a–d furn‐ ished the same 1,3,4‐thiadiazol‐2‐ylidene derivatives 11a–d . The 7‐arylhydrazono‐1,2,4‐triazolo[3,4‐ b ]‐1, 3,4‐thiadiazine derivatives 12a–d were obtained either by treatment of 4‐amino‐1,2,4‐triazole‐5‐thione 5 with hydrazonoyl halides 10a–d or by coupling of the 1,2,4‐triazolo[3,4‐b]‐1,3,4‐thiadiazine derivative 8 with diazonium salts. © 2005 Wiley Periodicals, Inc. Heteroatom Chem 16:621–627, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20162 相似文献
12.
The reaction of 2H‐2‐oxobenzo[b]pyran‐3‐hydrazide ( 2 ) with carbon disulfide in basic DMF afforded potassium thiocarbamate 3 , which readily underwent heterocyclization upon its reaction with hydrazine and/or phenacyl bromide to yield 1,2,4‐tiazole ( 4 ) and thiazole 7 derivatives, respectively. Condensation of 4 with substituted phenacyl bromide and/or chloranil gave 1,2,4‐triazole[3,4‐b]thiadiazine ( 5a,b ) and 3,10‐bis‐[2H‐2‐oxobenzo[b]pyran‐3‐yl]‐6,13‐dichloro‐bis‐1,2,4‐triazolo[3,4‐b]‐1,3,4‐thiadiazino[5′,6′‐b:5′,6′‐e]cyclohexa‐1,4‐diene ( 6 ), respectively. Cyclization of thiosemicarbazide 10 by refluxing it in sodium hydroxide and/or phosphoryl chloride afforded triazole 13 and thiadiazole 15 derivatives, respectively. Also, 10 reacted with phenacyl bromide in the presence of anhydrous sodium acetate to give the oxothiazolidine derivative 17 . The structure of the synthesized compounds were confirmed by elemental analyses, IR, 1H NMR, and mass spectra. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:114–120, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10109 相似文献
13.
Błażej Gierczyk Michał Cegłowski Marcin Kaźmierczak Maciej Zalas 《Magnetic resonance in chemistry : MRC》2012,50(9):637-641
The 1H, 13C and 15N spectra of aryl‐substituted 1,3,4‐thiadiazoles were recorded. The results obtained were correlated with Hammett coefficients. The experimental results were compared with DFT‐calculated chemical shifts. The results obtained were compared with those for 1,3,4‐oxadiazoles and 1,3,4‐selenadiazoles. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
14.
Substituted thiosemicarbazones 7a–e reacted with ethenetetracarbonitrile (TCNE) in ethyl acetate with formation of 5‐amino‐3‐(substituted ben‐zylidene‐amino)‐2‐phenylimino‐2,3‐dihydrothiazole‐4‐carbonitrile 8a–e 2‐amino‐6‐phenyl‐imino‐1,6‐ dihydropyrrolo[1,3,4]thiadiazine‐3‐carbonitrile 9 , and phenyl‐(5‐{substituted phenyl}‐3H‐[1,3,4]thiadiazole‐2‐ylidene)amines 10a–e . Rationales for the observed conversations are presented. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:261–266, 2006; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/hc.20198 相似文献
15.
In an effort to decrease the electron‐injection barrier from the anode electrode, four copoly(aryl ether)s ( P1 – P4 ), consisting of alternating isolated electron‐transporting [2,5‐diphenyl‐1,3,4‐oxadiazole for P1 and P3 and 5,5′‐diphenyl‐2,2′‐p‐(2,5‐bishexyloxyphenylene)‐bis‐1,3,4‐oxadiazole for P2 and P4 ] and emitting chromophores (1,4‐distyryl‐2,5‐dihexyloxybenzene for P1 and P2 and 1,4‐distyryl‐2,5‐dihexylbenzene for P3 and P4 ), have been synthesized by the nucleophilic displacement reaction between bisfluoride and bisphenol monomers. They are basically amorphous materials with 5% weight‐loss temperature above 400 °C. The photoluminescence spectra and quantum yields of these copolymers are dependent on the compositions of the two isolated fluorophores. The highest occupied molecular orbital and lowest unoccupied molecular orbital energy levels of these copolymers have been estimated from their cyclic voltammograms. All the observations directly prove that the oxidation starts at the hole‐transporting segments. The electron affinity can be enhanced by the introduction of isolated electron‐transporting segments that lead to a charge‐injection balance. Single‐layer light‐emitting diodes (Al/ P1 – P4 /ITO glass) have been fabricated. P1 and P2 reveal blue electroluminescence, and P3 and P4 reveal purple‐blue electroluminescence. Moreover, the incorporation of bisoxadiazole units increases the electron affinity and reduces the turn‐on electric field better than one oxadiazole unit. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2765–2777, 2003 相似文献
16.
Y. A. Ammar M. M. Ghorab A. M. Sh. El‐Sharief Sh. I. Mohamed 《Heteroatom Chemistry》2002,13(3):199-206
Several s‐triazoles 2, 7a, 10, 12 ; s‐triazolo[3,4‐b][1,3,4]thiadiazines ( 3–5 ); s‐triazolo[3,4‐b][1,3,4]thiadiazoles ( 6, 8, 11, 15 ); and s‐triazolo[3,4‐b][1,3,4]thiadiazepine ( 14 ) were synthesized starting from 2‐(6‐methoxy‐2‐naphthyl)propanoic acid ( 1 ) (Naproxen). The structures of the synthesized compounds were elucidated by elemental analyses and spectral data. Compounds 2, 5, 11, 12, 14 , and 15 exhibited a remarkable antifungal activity compared with the standard fungicide Mycostatine. Radiosterilization of the biologically active compounds 2, 5, 11 , and 14 in the dry state may prove to be applicable (retaining their structures unchanged up to 40 kGy). © 2002 Wiley Periodicals, Inc. Heteroatom Chem 13:199–206, 2002; Published online in Wiley Interscience (www.interscience.wiley.com). DOI 10.1002/hc.10019 相似文献
17.
Moriyuki Sato Shinji Nakashima Yuko Uemoto 《Journal of polymer science. Part A, Polymer chemistry》2003,41(17):2676-2687
Thermotropic liquid‐crystalline (LC) semirigid polyesters based on three terphenyl analogues of 1,3,4‐thiadiazole (2,5‐diphenyl‐1,3,4‐thiadiazole)s (DPTD) linking undecamethyleneoxy chain at different substituted positions were synthesized from three disubstituted (4,4′‐, 3,4′‐, and 3,3′‐) dioxydiundecanols of DPTD and four diesters, and the relationships between polymer structures and LC and optical properties were investigated. DSC measurements, texture observations, and wide‐angle X‐ray analyses revealed that the polymers composed of DPTD moiety having a more linear molecular structure and 1,4‐phenylene unit or short aliphatic chain tend to exhibit LC smectic C and/or A phases. The following observations were made: (1) the emergence of smectic C and/or A phases in all the polymers on the basis of 4,4′‐disubstituted DPTD, (2) formation of enantiotropic smectic C and/or A phases in the polymers containing a 1,4‐phenylene unit in the main chain, (3) formation of a more stable smectic C phase in the polymers having a short aliphatic [(CH2)4] chain, and (4) a decrease of the mesomorphic property of the polyesters in the order of 4,4′‐DPTD > 3,4′‐DPTD > 3,3′‐DPTD. Solution and solid‐state ultraviolet–visible and photoluminescent spectra indicated that all the polyesters display maximum absorbances and blue emissions arising from the DPTD moiety, whose peak maxima were shifted to lower wavelengths in the order of 4,4′‐DPTD > 3,4′‐DPTD > 3,3′‐DPTD as well as the aforementioned LC property. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2676–2687, 2003 相似文献
18.
《Magnetic resonance in chemistry : MRC》2003,41(9):689-692
15N NMR chemical shifts of 2‐aryl‐1,3,4‐oxadiazoles were assigned on the basis of the 1H–15N HMBC experiment. Chemical shifts of the nitrogen and carbon atoms in the oxadiazole ring correlate with the Hammett σ‐constants of substituents in the aryl ring (r2 ≥ 0.966 for N atoms). 15N NMR data are a suitable and sensitive means for characterizing long‐range electronic substituent effects. Additionally, 13C NMR data for these compounds are presented. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
19.
Natsuko Sato Ken Tanaka Shunsuke Masaki Shinichi Yamazaki Kunio Kimura Ai Nishichi 《Journal of polymer science. Part A, Polymer chemistry》2007,45(14):2855-2866
Fluorine‐containing poly(aryl ether 1,3,4‐ozadiazole)s were synthesized by the nucleophilic aromatic substitution reaction of 2,5‐bis(2,3,4,5,6‐pentafluorophenyl)‐1,3,4‐oxadiazole and various bisphenols in the presence of potassium carbonate. The polymerizations were carried out at 30 °C in 1‐methyl‐2‐pyrrolidinone to avoid the gelation caused by a crosslinking reaction at para and ortho carbons to the 1,3,4‐oxidiazole ring. The obtained polymers were all para‐connected linear structures. The obtained fluorine‐containing poly(aryl ether 1,3,4‐ozadiazole)s showed excellent solubility and afforded tough, transparent films by the solution‐casting method. They also exhibited a high glass transition temperature depending on the molecular structure, and the glass transition temperature could be controlled by the bisphenols in the range of 157–257 °C. They showed good thermal stability and excellent hydrophobicity due to the incorporation of the 2,3,5,6‐tetrafluoro‐1,4‐phenylene moiety. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2855–2866, 2007 相似文献
20.
Zheng‐Jun Quan Rong‐Guo Ren Yu‐Xia Da Zhang Zhang Xi‐Cun Wang 《Heteroatom Chemistry》2011,22(5):653-658
Treatment of mercapto‐heterocyclic compounds with diethyl phosphite in the presence of 4‐dimethylaminopyridine (DMAP) in tetrachloroethylene has given the S‐ethylated product in good yields and high chemoselectivity. This procedure is compatible with a wide range of SH‐compounds such as 1,3,4‐oxadiazole‐2‐thiol, 1,3,4‐thiadiazole‐2‐thiol, benzo[d]thiazole‐2‐thiol, and substituted benzenethiol. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 22:653–658, 2011; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20729 相似文献