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1.
Reaction of 4H‐pyrimido[2,1‐b]benzothiazole‐2‐thiomethyl‐3‐cyano‐4‐one (1) with hydrazine hydrate/aryl hydrazine/heteryl hydrazine in the presence of anhydrous potassium carbonate and dimethyl formamide afforded 3‐amino‐4‐oxo‐(2H)/aryl/heteryl pyrazolo[3′,4′:4,5]pyrimido[2,1‐b]benzothiazoles in good yield. These pyrazole derivatives on diazotization followed by replacement with hydroxy, chloro, bromo, iodo and on reduction gave the corresponding 3‐substituted derivatives. 相似文献
2.
Sambhaji P. Vartale Nilesh K. Halikar Shivraj B. Sirsat Yogesh D. Pawar 《Journal of heterocyclic chemistry》2013,50(2):351-354
Pyrazolo pyrimido pyrimidine ( 4a–k ) was prepared by the reaction of compound 3‐cyano‐4‐imino‐2‐(methylthio)4H‐pyrido[1,2‐a]pyrimidine ( 3 ) with hydrazine hydrate, phenyl hydrazine, 2‐hydrazino benzothiazole, and 6‐substituted hydrazine benzothiazole in N,N‐dimethylformamide and anhydrous potassium carbonate. These synthesized compounds were characterized by elemental analysis IR, 1H NMR, and mass spectral data. 相似文献
3.
Ahmet ener M. Kasim ener Ishak Bildmci Rahmi Kasimogullari Yunus Akamur 《Journal of heterocyclic chemistry》2002,39(5):869-875
The 1H‐pyrazole‐3‐carboxylic acid 2 , obtained from the furan‐2,3‐dione 1 and N‐Benzylidene‐N'‐(3‐nitrophenyl) hydrazine, was converted via reactions of its acid chloride 3 with various alcohols or N‐nucleo‐philes into the corresponding ester or amide derivatives 4 or 5 , respectively. Nitrile 6 and anilino‐pyrazole acid 7 derivatives of 2 were also obtained by dehydration of 5a in a mixture of SOCl2 with DMF and reduction of 2 with sodium polysulphide, respectively. While cyclocondensation reactions of 2 or 7 with phenyl hydrazine or hydrazine hydrate and 6 with only anhydrous hydrazine lead to derivatives of pyrazolo[3,4‐d]‐pyridazinone 8 and pyrazolo[3,4‐d]pyridazine amine 9 , respectivel. The reaction of 2 with 2‐hydrazinopyri‐dine provided hydrazono‐pyrazole acid derivative 10 , which was decarboxylated to give hydrazono‐pyra‐zole derivative 11 . Pyrazolo[4,3‐d]oxazinone 12 and 2‐quinolyl pyrazolo[3,4‐d]pyridazine 13 derivatives were also prepared by cyclocondensation reactions of 2 with hydroxylamine hydrochloride and 7 with acetaldehyde, respectively. 相似文献
4.
The electrochemical behaviour of hydrazine at a 1‐benzyl‐4‐ferrocenyl‐1H‐[1,2,3]‐triazole‐triazole/carbon nanotube modified glassy carbon electrode has been studied. The modified electrode shows an excellent electrocatalytic activity for the oxidation of hydrazine and accelerates electron transfer rate. The electrocatalytic current increases linearly with hydrazine concentration in the range 0.5–700.0 μm and the detection limit for hydrazine was 33.0 ± 2.0 nm . The diffusion coefficient (D = 2.5 ± 0.1 × 10?5 cm2 s?1) and kinetic parameters such as the electron transfer coefficient, (α = 0.52) and the heterogeneous rate constant (k′ = 5.5 ± 0.1 × 10?3 cm s?1) for hydrazine were determined using electrochemical approaches. Finally, the method was employed for the determination of hydrazine in water samples. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
5.
Venkatapuram Padmavathi Akula Balaiah Dandu Bhaskar Reddy 《Journal of heterocyclic chemistry》2002,39(4):649-653
The 1,5‐diaryl‐3,3‐disubstituted‐1,5‐pentanedione on reaction with ammonium acetate, phosphorus pentoxide and phosphorus pentasulfide gave respective 1,4‐dihydropyridine, 4H‐pyran and 4H‐thiopyran. Novel spiro heterocycles have been obtained by the cyclocondensation of 4H‐thiopyran with hydrazine, hydroxylamine, urea and thiourea. 相似文献
6.
Ahmet Şener İshak Bildirici İsrafil Tozlu Hasan Genç Kadir Arısoy 《Journal of heterocyclic chemistry》2007,44(5):1077-1081
1,5‐Diphenyl‐1H‐pyrazole‐3,4‐dicarboxylic acid‐4‐ethyl ester 2 , obtained from the 4‐ethoxycarbonyl‐5‐phenyl‐2,3‐furandione 1 and N‐benzylidene‐N′‐phenyl hydrazine, was converted via reactions of its acid chloride 3 with various alcohols or N‐nucleophiles into the corresponding ester 5 or amide derivatives 6 , respectively. In addition, 2 was decarboxylated to give ethyl 1,5‐diphenylpyrazole‐4‐carboxylate 4 . Nitrile 7 derivative of 2 was also obtained by dehydration of 6a in a mixture of SOCl2 and DMF. While cyclocondensation reaction of 2 with hydrazine hydrate leads to the formation of pyrazolo[3,4‐d]pyridazine‐4,7‐dione 8 , the reaction of 3 with anhydrous hydrazine provided a new bis pyrazole derivative 9 . 相似文献
7.
Aryl‐furyl substituted pyrazolines 2a–c and 4a–c were prepared by the reaction of α,β‐unsaturated carbonyl compounds with hydrazine or phenyl hydrazine. N‐chloroacetyl derivatives 3a–c were obtained by the N‐acetylation of 2a–c . The antibacterial activities of synthesized pyrazolines were examined by employing the disk‐diffusion technique. All synthesized compounds showed antibacterial effects in 1200 μg concentration. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:345–347, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10159 相似文献
8.
Heba Hassan 《Journal of heterocyclic chemistry》2019,56(2):646-650
Unexpectedly, the reaction of 1‐ethyl‐4‐hydroxyquinolin‐2(1H)‐one ( 1 ) with hydrazine hydrate and/or hydrazine dihydrochloride led to three different products. In addition to the expected quninolinylhydrazine, two heteropentacycles, diquinopyrrole and diquinopyridazine, were afforded, depending on reaction conditions. The structure of the new products was established upon their spectral and analytical data. 相似文献
9.
Action of Hydrazines on 2‐(2‐Oxindolin‐3‐ylidene)malononitrile, (E,Z)‐Ethyl 2‐cyano‐2‐(2‐oxindolin‐3‐ylidene)acetate and Isatin‐β‐thiosemicarbazone as a Source of Spiro Indoline‐pyrazole Systems 下载免费PDF全文
Ahmed S. A. Youssef Magdy M. Hemdan Samir A. Emara Rabaa M. Kamel 《Journal of heterocyclic chemistry》2015,52(5):1331-1336
2‐(2‐Oxindolin‐3‐ylidene)malononitrile ( 1a ) or (E,Z)‐ethyl 2‐cyano‐2‐(2‐oxindolin‐3‐ylidene)acetate ( 1b ) or isatin‐β‐thiosemicarbazone ( 1c ) undergoes reactions with prototype hydrazine hydrate itself and some of its simple congeners to give hydrazone derivatives bearing indoline‐2‐one moiety ( 2 ). The hydrazone derivatives ( 2 ) when heated with acetyl acetone or ethyl acetoacetate in dry pyridine afforded the spiro indoline derivatives ( 3a , 3b ). Also, cinnoline derivative ( 9 ) is obtained by action of hydrazine hydrate on the N‐acetyl derivative of ( 6a ). The structures of the newly synthesized compounds were evaluated by IR, 1H‐NMR spectroscopy, mass spectra and elemental analyses. 相似文献
10.
《Journal of heterocyclic chemistry》2017,54(1):147-150
Aldol condensation of 5,6‐dihydro‐4H‐pyrrolo[3,2,1‐ij ]quinoline‐1,2‐dione with aryl methyl ketones generates 3‐(aroylmethylidene)oxindoles, which react with hydrazine to generate tricyclic spiro[3H‐pyrazole‐3,3′‐oxindoles]. 相似文献
11.
An easy, simple and versatile one step synthesis of 3‐(2‐oxo‐2H‐chromen‐3‐yl)‐6H,8H‐pyrimido[4,5‐c]‐pyridazine‐5,7‐diones is reported by reaction of 3‐acetylcoumarins ( 1 ) with alloxan monohydrate ( 2 ) in acetic acid followed by hydrazine hydrate. 相似文献
12.
Nabila Aït‐Baziz Yahia Rachedi Maamer Hamdi Artur M. S. Silva F. Balegroune Roisnel Thierry N. Sellier 《Journal of heterocyclic chemistry》2004,41(4):587-591
The synthesis and reactivity studies of 4‐hydroxy‐6‐methyl‐3‐(5‐phenyl‐2E,4E‐pentadien‐1‐oyl)‐2H‐pyran‐2‐one 2 with nucleophiles are reported. Reactions of 2 with hydrazine derivatives gave new pyrazole‐type com pounds while the reaction with ortho‐phenylenediamines yielded 1,5‐benzodiazepines. The reaction of 2 with ethylamine implies the 2H‐pyran‐2‐one ring opening and the formation of a strong conjugated compound 3. 相似文献
13.
J. Wilson Quail John A. Weil Malvinder P. Singh 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):235-236
The title molecule (DMPH‐H), C8H9N5O6, was investigated to provide comparison with 2,2‐diphenyl‐1‐picrylhydrazine, which unlike DMPH‐H is readily oxidizable to form a well known stable free radical (DPPH). The structure shows essential differences in the configuration of the hydrazine‐N atoms, the ortho‐nitro group orientations and the crystal packing. The bond angles of the dimethylamino N atom [107.90 (13), 108.96 (12) and 112.21 (13)°] are consistent with a tetrahedral N atom and sp3 hybridization. 相似文献
14.
Liang Qiao Xiao-Gang Chen Ji-Xing Gao Yong Ai 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(6):728-733
The crystal structures of three quinuclidine‐based compounds, namely (1‐azabicyclo[2.2.2]octan‐3‐ylidene)hydrazine monohydrate, C7H13N3·H2O ( 1 ), 1,2‐bis(1‐azabicyclo[2.2.2]octan‐3‐ylidene)hydrazine, C14H22N4 ( 2 ), and 1,2‐bis(1‐azoniabicyclo[2.2.2]octan‐3‐ylidene)hydrazine dichloride, C14H24N42+·2Cl? ( 3 ), are reported. In the crystal structure of 1 , the quinuclidine‐substituted hydrazine and water molecules are linked through N—H…O and O—H…N hydrogen bonds, forming a two‐dimensional array. The compound crystallizes in the centrosymmetric space group P21/c. Compound 2 was refined in the space group Pccn and exhibits no hydrogen bonding. However, its hydrochloride form 3 crystallizes in the noncentrosymmetric space group Pc. It shows a three‐dimensional network structure via intermolecular hydrogen bonding (N—H…C and N/C—H…Cl). Compound 3 , with its acentric structure, shows strong second harmonic activity. 相似文献
15.
2‐Alkyl and 2‐arylhydrazine derivatives of 5H‐2‐R‐6‐fluoro‐7‐methyl‐1,3,4‐thiadiazolo[3,2‐a]pyrimidin‐5‐one were prepared by reaction of 5H‐2‐bromo‐6‐fluoro‐7‐methyl‐1,3,4‐thiadiazolo[3,2‐a]pyrimidin‐5‐one with hydrazine derivatives. A convenient procedure was developed for the preparation of new hydrazine derivatives of 5H‐2‐R‐6‐fluoro‐7‐methyl‐1,3,4‐thiadiazolo[3,2‐a]pyrimidin‐5‐one. J. Heterocyclic Chem., (2011). 相似文献
16.
The reaction of dibenzylideneacetones or E,E‐cinnamylidene‐ acetophenones and hydrazine hydrate provided 1‐propionyl derivatives of 5‐aryl‐3‐styryl‐2‐pyrazolines and 3‐aryl‐5‐styryl‐2‐pyrazolines. These unsaturated ketones afforded 1‐(2‐carboxyphenyl) or 1‐(4‐carboxyphenyl) 5‐aryl‐3‐styryl‐2‐pyrazolines and 1‐(4‐carboxyphenyl) derivatives of 3‐aryl‐5‐styryl‐2‐pyrazolines on treatment with (2‐carboxyphenyl)‐hydrazine or (4‐carboxyphenyl)hydrazine in hot acetic acid. Structures of all new 2‐pyrazolines have been elucidated by microanalyses and a combined utilization of various spectroscopic methods. 相似文献
17.
Formation of Dialkyl 2‐[3‐Alkoxy‐1‐(alkylimino)‐1‐chloro‐3‐oxopropan‐2‐ylidene]hydrazine‐1,1‐dicarboxylates of α‐(Alkoxycarbonyl)imidoyl Chlorides from PhosphineDiazo Ester Zwitterions and Nef‐Isocyanide Adducts 下载免费PDF全文
A novel transformation involving phosphine? diazo ester zwitterions (generated from dialkyl azodicarboxylates with Ph3P) and α‐(alkoxycarbonyl)imidoyl chlorides (prepared from α‐addition of acyl chlorides to alkyl isocyanides) to afford dialkyl 2‐[3‐alkoxy‐1‐(alkylimino)‐1‐chloro‐3‐oxopropan‐2‐ylidene]hydrazine‐1,1‐dicarboxylates in moderate yields, is described. 相似文献
18.
Said Ahmed Soliman Ghozlan Ismail Abdelshafy Abdelhamid Mohamed Hilmy Elnagdi Hatem Moustafa Gaber 《Journal of heterocyclic chemistry》2005,42(6):1185-1189
3‐Diethylaminoacrylonitrile ( 1 ) reacts with hydrazonyl halides ( 2a‐d ) to yield 1,3‐disubstituted pyrazole‐4‐carbonitriles 5a‐d. The acetyl 1‐p‐chlorophenylpyrazole‐4‐carbonitrile ( 5a ) condensed with hydrazine hydrate to yield the bishydrazone 10 and with dimethylformamide dimethylacetal to yield 1‐aryl‐3‐(3‐dimethylamino)acryloyl pyrazole‐4‐carbonitrile ( 11 ). This enamine reacts with hydrazine hydrate to yield the pyrazolylpyrazole ( 12 ) and with naphthoquinone to yield the 3‐naphthofuranoyl pyrazole 13. The pyra‐zolyl pyridine derivative 14 was obtained upon treatment of 11 with acetylacetone in the presence of ammonium acetate. Compound 11 was coupled with p‐chlorobenzene diazonium chloride to yield the hydrazone 16 that was coupled further with p‐chlorobenzenediazonium chloride to yield the formazane 18. 相似文献
19.
Udo Beckmann Sally Brooker 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(11):o653-o655
The structure of the cocrystallized 1:1 adduct of (S,S)‐4‐amino‐3,5‐bis(1‐hydroxyethyl)‐1,2,4‐triazole and (S,S)‐1,2‐bis(2‐hydroxypropionyl)hydrazine, C6H12N4O2·C6H12N2O4, has tetragonal symmetry. All eight O‐ and N‐bound H atoms are involved in intermolecular hydrogen bonds, resulting in infinite zigzag chains of the triazole molecules, with the hydrazine molecules filling the gaps between the chains and completing a three‐dimensional hydrogen‐bonded array. 相似文献
20.
Yoshihisa Kurasawa Waka Satoh Izumi Matsuzaki Yuka Maesaki Yoshihisa Okamoto Ho Sik Kim 《Journal of heterocyclic chemistry》2003,40(5):837-843
The reaction of the quinoxaline N‐oxides 7a,b with diethyl ethoxymethylenemalonate gave the 1‐methylpyridazino[3,4‐b]quinoxaline‐4,4‐dicarboxylates 8a,b , whose reaction with N‐bromosuccinimide or N‐chlorosuccinimide afforded the 3‐halogeno‐1‐methylpyridazino[3,4‐b]quinoxaline‐4,4‐dicarboxylates 9a‐d. The reaction of compounds 9a‐d with hydrazine hydrate resulted in hydrolysis and decarboxylation to provide the 3‐halogeno‐1‐methylpyridazino[3,4‐b]quinoxaline‐4‐carboxylates 10a‐d , whose reaction with nitrous acid effected oxidation to furnish the 3‐halogeno‐4‐hydroxy‐1‐methylpyridazino[3,4‐b]quinoxaline‐4‐carboxylates 11a‐d , respectively. The reaction of compounds 11a‐d with hydrazine hydrate afforded the 3‐halogeno‐1‐methylpyridazino[3,4‐b]quinoxalin‐4‐ols 12a‐d , whose oxidation provided the 3‐halogeno‐1‐methylpyridazino[3,4‐b]quinoxalin‐4(1H)‐ones 6a‐d , respectively. Compounds 6a‐d had antifungal activities in vitro. 相似文献