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Artículos de revistas sobre el tema "Hydroxylamine derivatives"

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Publicado: 18 de mayo de 2024

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1

Reissig, Hans-Ulrich y Reinhold Zimmer. "Cyclizations of Alkoxyallenes: Mechanisms, Intermediates, ­Products – A Personal Account on Solved and Unsolved Problems with Unique Allene Building Blocks". Synthesis 49, n.º 15 (6 de junio de 2017): 3291–302. http://dx.doi.org/10.1055/s-0036-1588846.

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The additions of lithiated alkoxyallenes to electrophiles, such as carbonyl compounds, thioketones, imines, and nitrones, provide the expected primary addition products. These alkoxyallene intermediates undergo ring-closure reactions under quite different conditions. Whereas allenyl hydroxylamine derivatives spontaneously cyclize to 1,2-oxazine derivatives, the related allenyl amines, thiols, and alcohols require, with distinct exceptions, promotion by acids, base, silver(I), or gold(I). The different mechanisms of these processes are discussed in this account. The serendipitous discovery of a novel three-component reaction of lithiated alkoxyallenes, nitriles, and carboxylic acids followed by a cyclization to pyridine derivatives is also reported and the mechanism involved is illustrated. This account also compiles exemplary examples of natural products and other compounds prepared by subsequent reactions of alkoxyallene-based cyclization products, but the fascinating ring-closing event of the allenyl intermediates is the main focus of this report.1 Introduction2 Cyclizations of Allenyl Hydroxylamines to 1,2-Oxazine Derivatives3 Cyclizations of Allenyl Amines to Dihydropyrrole Derivatives4 Cyclizations of Allenyl Imines to Pyrroles – Discovery of a New Three-Component Synthesis of Pyridines5 Cyclizations of Allenyl Thiols to Vinylthiiranes and Dihydrothiophene Derivatives6 Cyclizations of Allenyl Alcohols to Dihydrofuran Derivatives7 Conclusions
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2

Rehse, Klaus y Tawfig Shahrouri. "Hydroxylamine Derivatives". Archiv der Pharmazie 331, n.º 11 (noviembre de 1998): 365–67. http://dx.doi.org/10.1002/(sici)1521-4184(199811)331:11<365::aid-ardp365>3.0.co;2-n.

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3

Torruellas, Carilyn, Fu-Lian Hsu y Andrew J. Walz. "Synthesis of N-Pyridyl Hydroxylamines via Copper-Catalyzed Cross-Coupling". Synthesis 51, n.º 15 (15 de mayo de 2019): 2891–96. http://dx.doi.org/10.1055/s-0037-1611836.

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N-Pyridyl hydroxylamine derivatives were prepared via copper-catalyzed cross-coupling of orthogonally functionalized hydroxylamines with iodopyridines. Various amino- and hydroxyl-protecting groups were tolerated. A total of 20 examples were synthesized in 28–90% yield.
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4

Pískala, Alois, Naeem B. Hanna, Milena Masojídková, Pavel Fiedler y Ivan Votruba. "Synthesis of N4-Amino and N4-Hydroxy Derivatives of 5-Azacytidine. A Facile Rearrangement of the N4-Amino Derivative to 5-(3-β-D-Ribofuranosylureido)-1H-1,2,4-triazole". Collection of Czechoslovak Chemical Communications 69, n.º 4 (2004): 905–17. http://dx.doi.org/10.1135/cccc20040905.

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Treatment of methoxyribosyltriazinone 4 with hydrazine in methanol afforded crude 4-hydrazino-1-β-D-ribofuranosyl-1,3,5-triazin-2(1H)-one (N4-amino-5-azacytidine) (2), which rearranged rapidly to isomeric 5-ribosylureidotriazole 6. The rearrangement proceeds easily also in water solutions of 2. Alkaline hydrolysis of 6 gave a mixture of 5-ureidotriazole 7 and 5-aminotriazole 8. Acid hydrolysis of 6 afforded only 7. This compound was also prepared by thermal rearrangement of 5-amino-1-carbamoyltriazole 9 or on reaction of cyano(formyl)guanidine 10 with hydrazine hydrochloride. Treatment of benzoylated methoxyribosyltriazinone 4a with hydrazine in methanol gave only the rearranged product 6a. Reaction of tribenzoylribosyl isocyanate 12 with aminotriazole 8 gave 1-triazolecarboxamidotribenzoylribose 13, which afforded by methanolysis oxazoloribofuranose 14 and aminotriazole 8. Compound 14 was also obtained by methanolysis of blocked ribosylcarbamate 16. Reaction of methoxyribosyltriazinone 4 with hydroxylamine in methanol afforded 4-hydroxylamino-1-β-D-ribofuranosyl-1,3,5-triazin-2(1H)-one (N4-hydroxy-5-azacytidine) (3), which on the action of excess hydroxylamine yielded 1-cyano-1-hydroxy-5-β-D-ribofuranosylisobiuret (19). Treatment of methoxy-1,3,5-triazinone 18 with a solution of hydroxylamine in methanol gave 4-hydroxylamino-1-methyl-1,3,5-triazin-2(1H)-one (N4-hydroxy-1-methyl-5-azacytosine) (17). Heating of cyano(formyl)guanidine 10 with hydroxylamine hydrochloride in water lead to the formation of triuret (21). The mechanisms of the reactions of methoxyribosyltriazinone 4 with hydrazine and hydroxylamine are discussed. Compounds 2, 6 and 19 exhibited no significant antibacterial or cytostatic activity.
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5

Baldauf, Simon y Jeffrey Bode. "Synthesis and Evaluation of Cyclic Acetals of Serine Hydroxylamine for Amide-Forming KAHA Ligations". Synthesis 51, n.º 05 (7 de enero de 2019): 1273–83. http://dx.doi.org/10.1055/s-0037-1611635.

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The α-ketoacid–hydroxylamine (KAHA) ligation allows the coupling of unprotected peptide segments. The most widely used variant employs a 5-membered cyclic hydroxylamine that forms a homoserine ester as the primary ligation product. While very effective, monomers that give canonical amino acid residues are in high demand. In order to preserve the stability and reactivity of cyclic hydroxylamines, but form a canonical amino acid residue upon ligation, we sought to prepare cyclic derivatives of serine hydroxylamine. An evaluation of several cyclization strategies led to cyclobutanone ketals as the leading structures. The preparation, stability, and amide-forming ligation of these serine-derived ketals are described.
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6

Veits, Gesine K., Donald R. Wenz, Leoni I. Palmer, André H. St. Amant, Jason E. Hein y Javier Read de Alaniz. "Cascade rearrangement of furylcarbinols with hydroxylamines: practical access to densely functionalized cyclopentane derivatives". Organic & Biomolecular Chemistry 13, n.º 31 (2015): 8465–69. http://dx.doi.org/10.1039/c5ob00944h.

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The aza-Piancatelli rearrangement with hydroxylamines to 4-aminocyclopentenones is described. Subsequent transformations highlight the versatility of the cyclopentene scaffold and the value of the hydroxylamine in this transformation.
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7

Spooren, Anita AMG y Chris TA Evelo. "Only the glutathione dependent antioxidant enzymes are inhibited by haematotoxic hydroxylamines". Human & Experimental Toxicology 17, n.º 10 (octubre de 1998): 554–59. http://dx.doi.org/10.1177/096032719801701005.

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Hydroxylamine and some of its derivatives are known to cause oxidative effects both in vitro and in vivo.Inthe current study we investigated the effects of hydroxyla-mines on the enzymatic antioxidant defense system in human erythrocytes. The activity of catalase and super-oxide dismutase was not significantly influenced by any of the hydroxylamines tested. However, the activity of glutathione peroxidase (GPX) and glutathione S-transferase (GST) was strongly inhibited by hydroxylamine and its O-derivatives (O-methyl and O-ethyl hydroxylamine). GPX was also inhibited by two N-derivatives of hydro-xylamine (i.e. N-dimethyl and N, O-dimethyl hydroxyla-mine). This indicates that exposure to hydroxylamines not only changes the cellular oxidation-reduction status but also leads to inhibition of the glutathione dependent antioxidant enzymes. GST as well as GPX have cysteine residues at the active site of the enzymes. Such an accessible thiol group is generally susceptible to formation of protein-mixed disulphides or intramolecular disulphides. If these thiol groups are essential for activity this would be accompanied by an increase or decrease in the enzyme activity. In principle this is also true for glutathione reductase (GR), which in this study was only inhibited by N, O-dimethyl and N-methyl hydroxylamines. However, GR is capable to reduce these disulphides by taking up two electrons, either from its substrate NAPDH or from another reductant. Oxidation of these thiol groups in GR would thus not lead to impairment of GR activity. The fact that NODMH and NMH do decrease the GR activity can therefore only be explained by other modifications. The activity loss of GST and GPX on the other hand, is likely to involve oxidation of critical cysteine residues. The practical consequence of these findings is that the cellular prooxidant state that may arise in erythrocytes exposed to hydroxylamines can be further increased by activity loss of protective enzymes, which may decrease the average life span of the red blood cell.
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8

Guy, Michelle, Sally Freeman, John Alder y Simon Brandt. "The Henry reaction: spectroscopic studies of nitrile and hydroxylamine by-products formed during synthesis of psychoactive phenylalkylamines". Open Chemistry 6, n.º 4 (1 de diciembre de 2008): 526–34. http://dx.doi.org/10.2478/s11532-008-0054-z.

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AbstractA clandestine two-step route to psychoactive racemic phenylalkylamines utilises the Henry reaction. In the first step an aromatic aldehyde reacts with a nitroalkane to give the nitrostyrene intermediate. In the second step the nitrostyrene is reduced to the phenylalkylamine. An impurity profile of both steps was evaluated through the synthesis and analysis of common street derivatives. The formation of nitrile impurities in the nitroaldol reaction and hydroxylamine impurities in the reduction step were shown by NMR spectroscopy and GC-MS. A selection of reducing agents has been used to give the phenylalkylamines, together with variable quantities of the partially reduced hydroxylamine product. GC-MS analysis of the hydroxylamines showed heat-induced disproportionation which led to the detection of the corresponding oximes.
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9

Hashem, Heba E. y Ahmed M. Abo-Bakr. "Synthesis of Some New 1,2,4-Triazine and 1,2,5-Oxadiazine Derivatives with Antimicrobial Activity". Heteroatom Chemistry 2019 (25 de septiembre de 2019): 1–7. http://dx.doi.org/10.1155/2019/2326514.

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1,2,4-Triazine and 1,2,5-oxadiazine derivatives 2–12 were obtained from treated 1,3-oxazolone (1) with phenyl hydrazine or hydroxylamine hydrochloride. Chlorotriazine derivative 3 undergoing condensation reactions with different reagents produced new fused tetrazolo-triazine and triazino-quinazolinone derivatives. 1,2,5-Oxadiazine has been used as a synthon for the fused pyrazolo-oxadiazine derivative. The constitution of the prepared compounds was built up based on microanalytical and spectral data. Some of the new compounds were assessed for their antimicrobial activity.
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10

Anyun, Zhang, Hu Jingxin, Zhang Xianye y Wang Fangding. "Hydroxylamine derivatives in Purex Process". Journal of Radioanalytical and Nuclear Chemistry 230, n.º 1-2 (abril de 1998): 235–39. http://dx.doi.org/10.1007/bf02387470.

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11

M.G., Assy, Abdalha A.A. y Abdel Aziz A.E. "Synthesis and Antimicrobial Evaluation of Some New Benzoxazinone and Quinazolinone Derivatives". JOURNAL OF ADVANCES IN CHEMISTRY 8, n.º 1 (20 de diciembre de 2016): 1491–99. http://dx.doi.org/10.24297/jac.v8i1.4030.

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Ring opening reactions of benzoxazinone (2) with nitrogen and oxygen nucleophiles gave the corresponding benzamides (3)&(4) and benzoates (5).Quinazolinone derivatives (6) and (7) were obtained upon treatment of (2) with hydrazine hydrate and/or hydroxylamine hydrochloride.Triazole derivatives (8a – b) were obtained when (2) was subjected to react with semicarbazide and/or thiosemicarbazide respectively. Reaction of (2) with sodium azide gave a mixture of tetrazole derivative (9) and benzoimidazolone derivative (10). The antimicrobial activity of some synthesized compounds was examined against bacteria, fungi and yeast. Some of the tested compounds showed promising activities.
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12

El Ashry, El Sayed H., Laila Fathy Awad, Mohamed Nabil Abd Al Moaty y Omayma Kh Bdeewy. "A novel trans-amination process in 3-arylamino- 5,5-dimethylcyclohex-2-en-1-one with nucleophiles and antimicrobial activity of selected products". Mediterranean Journal of Chemistry 7, n.º 6 (7 de enero de 2019): 452–62. http://dx.doi.org/10.13171/mjc7619019140eshea.

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Reaction of dimedone with arylamines afforded the respective enaminones. Some N-acetyl derivatives were prepared. The reaction of enaminones with hydroxylamine was found to be dependent on the nature of the arylamine moiety and the molar ratio of hydroxylamine to give the mono-, di- or tri-oximes. Cyclization of the trioxime by acetic anhydride gave dihydrobenzo[c][1,2,5]oxadiazol-4(5H)-one-5-O-acetyloxime. Coupling of the synthesized enaminones with benzene diazonium chloride gave 2,4-bis-phenylhydrazones or a mixture of 2-mono hydrazones and bis-hydrazones depending on the nature of the arylamine moiety. Trans-amination of the arylamine of the bis hydrazones with hydroxylamine gave the same1,3-bis oxime derivative. The structures of the synthesized compounds were confirmed by IR, 1HNMR, 13C NMR spectra. The antimicrobial activity of some selected products showed promising results.
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13

El-Ghanam, Abdel Moneim. "New Route Synthesis of Styryl Pyrones: High Yield Synthesis, Reactions and Spectral Properties of 2-Phenyl-6-Styryl-4-Pyrones". Journal of Chemical Research 2005, n.º 10 (octubre de 2005): 654–56. http://dx.doi.org/10.3184/030823405774663101.

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2-Phenyl-6-styryl-4-pyrone derivatives have been synthesised from the reaction of ethyl phenylpropiolate with benzylideneacetone derivatives in the presence of sodium ethoxide. Treatment of styrylpyrone with phosphorus pentasulfide gave the corresponding styrylpyran-4-thione which on treatment with hydroxylamine hydrochloride and aqueous methylamine afforded the corresponding oxime and 1-methyl-2-phenyl-6-styrylpyridine-4(1H)-thione, respectively. On the other hand, styrylpyran-4-thione reacted with malononitrile to give pyrolylidenemalononitrile which on treatment with bidentate reagents, hydrazine hydrate, hydroxylamine hydrochloride, thiourea, and thiosemicarbazide afforded the corresponding styrylspiropyran derivatives of pyrazole, 1,2-oxazole or 1,3-thiazine, respectively.
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14

Mohammed, Jihad Haji, AKRAM Noori Mohammed QADDO, Nabaz Abdulmajeed Mohammad Salih y Faeza Burhan Omar. "The Synthesis of Some Imine Derivatives via Condensation Reactions between Some Aromatic Phenylhydroxylamine Derivatives with Glyoxylic Acid and the Study of their biological activity". Tikrit Journal of Pure Science 28, n.º 6 (25 de diciembre de 2023): 34–41. http://dx.doi.org/10.25130/tjps.v28i6.1411.

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This study investigated the condensation reactions between N-(3,4-dimethoxybenzyl)hydroxylamine and N-(4-methylbenzyl)hydroxylamine with glyoxalic acid. The objective was to obtain imine derivatives as the desired target products. FT-IR, 1H-NMR, and 13C-NMR spectroscopic techniques were used to identify the structures of the produced compounds. Different conditions were considered for these reactions and only N-(3,4-dimethoxybenzyl)hydroxylamine could be converted to the desired nitrone. Finally, the antimicrobial efficacy was assessed in terms of its action against the bacteria Escherichia coli (E.coli) as Gram-negative bacteria, Staphylococcus aureus (S.aureus) as Gram-positive bacteria and fungus (Candida albicans). The activity data proved that this nitrone showed significant antimicrobial activity compared to standard drugs.
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15

Schmid, G. H., K. P. Bader, A. Radunz, C. J. van Assche, N. Reinier y B. Courtiade. "Effect of Hydroxylamine Derivatives on Photorespiration in the Tobacco Aurea Mutant Nicotiana tabacum Su/su". Zeitschrift für Naturforschung C 42, n.º 7-8 (1 de agosto de 1987): 965–69. http://dx.doi.org/10.1515/znc-1987-7-839.

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O-(p-nitrophenyl)-hydroxylamine affects the size of the Warburg effect measured in leaves of the tobacco aurea mutant Su/su. If leaves are treated with a 10-5 м aqueous solution of the hydroxylamine derivative the Warburg effect which is usually very high in this mutant, is practically reduced to zero. Thus, if in the control (the untreated leaf) the Warburg effect consists in an enhancement of CO2-fixation from 270 μmol CO2 fixed mg·chlorophyll-1·h-1 under 21% oxygen partial pressure to 530 μmol CO2 fixed · mg Chl-1 · h-1 under 3% oxygen, the treated sample yields the maximal rate of photosynthesis already under 21% oxygen partial pressure. At concentrations around 10-4 м the compound is toxic to the plants and inhibits CO2 fixation substantially. A second hydroxylamine derivative used in this study has an additional methyl group in the ortho position to the -O-NH2 group. This compound is already toxic to the plant at concentrations around 10-5 м at which O-(p-nitrophenyl)-hydroxylamine optimally enhances CO2 fixation at normal oxygen partial pressure. From our studies it appears that O-(p-nitrophenyl)-hy- droxylamine binds to ribulose-1.5-bisphosphate carboxylase inducing a conformational change of the enzyme. This is concluded from the observation that a monospecific antiserum to ribulose-1.5- bisphosphate carboxylase is exhausted at considerably higher enzyme concentrations when the enzyme has been treated with the hydroxylamine derivative prior to the antiserum addition. The observation is interpreted as being due to a conformational change induced by the compound, leaving less antigenic determinants accessible in the enzyme surface, when compared to the untreated control. The inhibition of photosynthetic CO2 fixation at high concentrations of both hydroxylamine derivative studied is due to the inhibition of photosynthetic electron transport on the donor side of photosystem II. a phenomenon which is known already for unsubstituted hydroxylamine from the literature. The inhibition of electron transport on the donor side is deduced from an analysis of fluorescence rise kinetics at room temperature.
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16

Möhrle, Hans y Robert Nießen. "Umsetzung von N-Alkylpyridinium-Salzen mit Hydroxylamin / Reaction of N-Alkylpyridinium Salts with Hydroxylamine". Zeitschrift für Naturforschung B 55, n.º 5 (1 de mayo de 2000): 434–42. http://dx.doi.org/10.1515/znb-2000-0514.

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1-Methylpyridinium salts showed no reaction with excessive hydroxylamine, but nicotinic acid derivatives in HMPT gave the corresponding N-oxides. 3-Acetyl-1-methylpyridinium iodide generated the hydroximino-pyridine 1-oxide 13 and the isoxazoles 14, 15E, and 15Z. 2- and 4-Cyano-l-methylpyridinium iodides underwent no ring cleavage, but altered only the functional group. However, the 3-cyano compound was converted into the corresponding pyridine N-oxides with carboxamide, hydroxyamidine and carbaldoxime groups.
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17

Zhou, Qishun, Bao Vu Ngoc, Grazyna Leszczynska, Jean-Luc Stigliani y Geneviève Pratviel. "Oxidation of 5-methylaminomethyl uridine (mnm5U) by Oxone Leads to Aldonitrone Derivatives". Biomolecules 8, n.º 4 (14 de noviembre de 2018): 145. http://dx.doi.org/10.3390/biom8040145.

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Oxidative RNA damage is linked to cell dysfunction and diseases. The present work focuses on the in vitro oxidation of 5-methylaminomethyl uridine (mnm5U), which belongs to the numerous post-transcriptional modifications that are found in tRNA. The reaction of oxone with mnm5U in water at pH 7.5 leads to two aldonitrone derivatives. They form by two oxidation steps and one dehydration step. Therefore, the potential oxidation products of mnm5U in vivo may not be only aldonitrones, but also hydroxylamine and imine derivatives (which may be chemically more reactive). Irradiation of aldonitrone leads to unstable oxaziridine derivatives that are susceptible to isomerization to amide or to hydrolysis to aldehyde derivative.
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18

Kirby, Georgina, Laurence Grimaud, Maxime R. Vitale, Guillaume Prestat y Farouk Berhal. "Iron(ii)-catalyzed intermolecular aziridination of alkenes employing hydroxylamine derivatives as clean nitrene sources". Green Chemistry 23, n.º 23 (2021): 9428–32. http://dx.doi.org/10.1039/d1gc03495b.

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19

Fallon, Gary D., Saba Jahangiri, Andris J. Liepa y Ruth C. J. Woodgate. "N,N-Dialkyl (N'-Chlorosulfonyl)chloroformamidines in Heterocyclic Synthesis. I. The Preparation of [1,2,3,5]Thiatriazole and [1,3,2,4]Oxathiadiazole Derivatives". Australian Journal of Chemistry 58, n.º 5 (2005): 332. http://dx.doi.org/10.1071/ch04295.

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N,N-Dialkyl (N′-chlorosulfonyl)chloroformamidines 1 react regiospecifically with hydrazine derivatives to give [1,2,3,5]thiatriazole dioxides. Reaction of 1 with hydroxamic acids and N-methyl hydroxylamine gave derivatives of [1,3,2,4]oxathiadiazole dioxide 7, a new heterocycle.
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20

Miyakoshi, Takeru y Hiroyuki Konno. "Improved synthesis of 2,4,6-trialkylpyridines from 1,5-diketoalkanes: the total synthesis of Anibamine". Organic & Biomolecular Chemistry 17, n.º 11 (2019): 2896–905. http://dx.doi.org/10.1039/c8ob02723d.

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21

Chen, N. y J. Xie. "N–O linkage in carbohydrates and glycoconjugates". Organic & Biomolecular Chemistry 14, n.º 47 (2016): 11028–47. http://dx.doi.org/10.1039/c6ob00120c.

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22

Möhrle, H. y R. Nießen. "Reaktionen von Isochinolinium-Salzen mit Hydroxylamin-Derivaten, 1. Mitteilung. N-(Nitrophenyl)-substituierte Verbindungen/Reactions of Isoquinolinium Salts with Hydroxylamine Derivatives, 1st Communication. N-(Nitrophenyl) Substituted Compounds". Zeitschrift für Naturforschung B 54, n.º 2 (1 de febrero de 1999): 225–33. http://dx.doi.org/10.1515/znb-1999-0211.

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N-(Nitrophenyl) substituted isoquinolinium salts reacted with nucleophiles of the hydroxylamine type to different products depending on the electron withdrawing strength of the substituent. Mononitro compound 8 produced only the cyclic hydroxylamine 9a, the trinitroderivative 5 solely the ring cleaved oximes. The dinitro substance 1 held an intermediate position and gave rise to a labile cyclic hydroxylamine and a more stable ring opened Z-enamine; hydroxylamine ethers generated cyclic products which showed in dimethylsulfoxide ring chain isomerism with the tautomers.
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23

Abdallah, Tayseer A., Abdellatif M. Salaheldin y Naglaa F. Radwan. "Studies With Enamines: Synthesis and Reactivity of 4-Nitrophenyl-1-piperidinostyrene. Synthesis of Pyridazine, Oxadiazole, 1,2,3-Triazole and 4-Aminopyrazole Derivatives". Zeitschrift für Naturforschung B 62, n.º 2 (1 de febrero de 2007): 261–66. http://dx.doi.org/10.1515/znb-2007-0218.

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4-Nitrophenyl-1-piperidinostyrene (4) reacts with an aromatic diazonium salt to afford the arylhydrazonal 6. The latter condenses with active methylene compounds to yield pyridazine derivatives, and with hydroxylamine hydrochloride to produce oxadiazole and 1,2,3-triazole derivatives. Compound 12 was reacted with chloroacetonitrile to afford 4-aminopyrazoles 15.
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24

Amr, Abdel-Galil E. "Synthesis of Some New Linear and Chiral Macrocyclic Pyridine Carbazides as Analgesic and Anticonvulsant Agents". Zeitschrift für Naturforschung B 60, n.º 9 (1 de septiembre de 2005): 990–98. http://dx.doi.org/10.1515/znb-2005-0914.

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A series of 2,6-disubstituted pyridine derivatives were prepared from 2,6-diacetylpyridine or 2,6- dicarbonyl pyridine dichloride as starting materials. Reaction of 2,6-diacetylpyridine 1 with hydroxylamine hydrochloride or different aromatic aldehydes afforded the corresponding 2,6-diacetylpyridine dioxime and 2,6-bis-[β -(2-thienyl)acryloyl]pyridine derivatives 2 and 3, respectively. Additionally, N2,N2‘-(pyridine-2,6-dicarbonyl)-L-amino acid hydrazides 5 were prepared starting from 2,6- dicarbonyl pyridine dichloride via the corresponding esters 4. Compound 3 was reacted with hydroxylamine hydrochloride to afford the 2,6-bis-[β -(2-thienyl)acryloyl-oxime]-pyridine derivative 6. Treatment of compounds 2 or 6 with phenyl isocyanate or phenyl isothiocyanate in refluxing dioxane gave the corresponding semicarbazide or thiosemicarbazide derivatives 7 and 8, respectively. Their treatment with toluene-3,5-diisocyanate afforded the macrocyclic semicarbzides 9 and 10, respectively. The chiral thiosemicarbazides 11a,b were however, prepared by treating compounds 5a,b with phenyl isothiocyanate followed by cyclization with sodium hydroxide (2N) yielding the triazoles 12a,b. Finally, the hydrazides 5a,b were treated with toluene-3,5-diisocyanate to afford the chiral macrocyclic tetrapeptide semicarbazides 13a,b in reasonable yields, while the expected cyclic dipeptide 14 was not formed. The structure assignments of the new compounds were based on chemical and spectroscopic evidence. The pharmacological screening showed that many of these compounds have good analgesic and anticonvulsant activities comparable to Voltarine® and Carbamazapine® used as reference drugs.
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25

Pouzar, Vladimír y Ivan Černý. "17-(O-(2-Carboxyethyl)oxime) Derivatives of Androstanes of 3-Hydroxy-5α-, -5β-, -5-ene and 3-Oxo-4-ene Series". Collection of Czechoslovak Chemical Communications 60, n.º 1 (1995): 137–49. http://dx.doi.org/10.1135/cccc19950137.

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Androstane 17-(O-(2-carboxyethyl)oxime) derivatives were prepared either by the reaction of 17-keto derivatives with corresponding substituted hydroxylamine or by the addition of 17-oximino derivatives to the alkyl acrylate and subsequent hydrolysis. Oxidation of the hydroxy group in position 3 in derivatives of this type was performed either by the Oppenauer reaction, transforming 5-ene derivatives into 3-oxo-4-enes, or with Jones reagent in the case of saturated 5α- or 5β-derivatives. Configuration 17E in the whole series of oximes was confirmed by the 1H and 13C NMR spectroscopy.
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26

Zhang, Guangyu y Jiaxi Xu. "[3,3] Sigmatropic Shifts and Applications of Hydroxylamine Derivatives". Chinese Journal of Organic Chemistry 41, n.º 8 (2021): 3002. http://dx.doi.org/10.6023/cjoc202103022.

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27

Raban, Morton, Van A. Martin y Leslie Craine. "Torsional barriers in quinolinone hydroxylamine and sulfenamide derivatives". Journal of Organic Chemistry 55, n.º 14 (julio de 1990): 4311–16. http://dx.doi.org/10.1021/jo00301a020.

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28

Hacking, M. A. P. J., F. van Rantwijk y R. A. Sheldon. "Lipase catalysed acylation of hydroxylamine and hydrazine derivatives". Journal of Molecular Catalysis B: Enzymatic 11, n.º 4-6 (enero de 2001): 315–21. http://dx.doi.org/10.1016/s1381-1177(00)00144-2.

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29

Ovakimyan, M. Zh, S. K. Barsegyan, N. M. Kikoyan y M. G. Indzhikyan. "Reactions of Phosphonioalkyl Derivatives of Phenylhydrazine and Hydroxylamine". Russian Journal of General Chemistry 75, n.º 7 (julio de 2005): 1069–73. http://dx.doi.org/10.1007/s11176-005-0369-9.

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30

Černý, Ivan, Helena Havlíková, Martin Hill, Richard Hampl y Vladimír Pouzar. "Synthetic Approach to 5α-Pregnanolone 19-[O-(Carboxymethyl)oxime] Derivatives". Collection of Czechoslovak Chemical Communications 69, n.º 9 (2004): 1805–17. http://dx.doi.org/10.1135/cccc20041805.

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Syntheses of 5α-pregnanolone derivatives (3-hydroxy-5α-pregnan-20-ones) with 3α- and 3β-configuration and 19-[O-(carboxymethyl)oxime] group were developed, starting from 19-hydroxy-20-oxopregn-5-en-3β-yl acetate. After catalytic hydrogenation, acetylation and ketone protection, the acetyl in position 3 was removed. To obtain the 3α-derivative, nitrite epimerization of the intermediate tosylate was performed before the introduction of methoxymethyl protecting group, while the 3β-derivative was protected directly. In both series, deacetylation, oxidation to an aldehyde and O-(carboxymethyl)hydroxylamine condenzation followed. Conversion to the methyl ester, simultaneous deprotection of positions 3 and 20, and alkaline hydrolysis gave the corresponding 19-[O-(carboxymethyl)oximes]. The nine- and ten-step syntheses described herein (yields 19.5 and 7.3%, respectively) gave the target compounds, designed as haptens for immunological use.
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31

Patel, Anjan, Andreas Hofinger y Thomas Rosenau. "Synthesis and analytical characterization of monomeric N-oxidized derivatives of α-tocopheramine". Monatshefte für Chemie - Chemical Monthly 152, n.º 8 (agosto de 2021): 959–66. http://dx.doi.org/10.1007/s00706-021-02805-8.

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Abstractα-Tocopheramine has shown great promises as a stabilizer for synthetic and natural polymers, but is also investigated in various biomedical scenarios. Many studies have been hampered by the fact that the oxidation products of α-tocopheramine have not yet been properly identified and their analytical data are still lacking. In the present study, we synthesized and fully analytically characterized all N-oxidation products that can form upon oxidation of α-tocopheramine in aqueous media, including the hydroxylamine, nitroso, and nitro derivative, in this way providing standards for the identification of the so far elusive byproducts. Synthesis and stability of the derivatives are discussed. Graphic abstract
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32

Sun, Bin, Shi Yin, Xiaohui Zhuang, Can Jin y Weike Su. "Selectfluor-induced C(sp2)–O coupling reaction of N-substituted anilines with hydroxylamine derivatives". Organic & Biomolecular Chemistry 16, n.º 33 (2018): 6017–24. http://dx.doi.org/10.1039/c8ob01348a.

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We developed a novel metal-free method for the construction of C(sp2)–O bonds via oxidative cross-coupling reactions between various N-substituted anilines and hydroxylamine derivatives just using commercially available Selectfluor as an oxidant.
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33

Plešek, Jaromír, Farzaneh Hosseinpour Rajabi, Veena Vangani y Jiří Fusek. "Constitution and Properties of the 8,8'-μ-(H2NO)=(1,2-C2B9H10)2-3-Co Bridged Cobaltaborane". Collection of Czechoslovak Chemical Communications 59, n.º 6 (1994): 1326–36. http://dx.doi.org/10.1135/cccc19941326.

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Constitution of 8,8'-μ-H2N(-O-)(1,2-C2B9H10)2-3-Co sandwich has been elucidated 17 years after its first synthesis, via high resolution NMR methods supplemented by mass spectrometry. The species gives relevant "oximes" with acetone and benzaldehyde and is quantitatively methylated to the N,N'-dimethyl derivative, which shows an interesting redox disproportionation to a triatomically bridged sandwich with a 8,8'-μ-O-CH=N(Me)- bridge between both ligands. Several other "peculiar" reactions of this dimethyl derivative are discussed. On reductive cleavage of the parent hydroxylamine the non-bridged 8-HO-8-H3N(1,2-C3B3H10)2-3-Co zwitterion is obtained. Mono-, di- and trimethylated derivatives of this non-bridged species are characterized.
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34

Slavíková, Tereza, Vladimír Pouzar y Ivan Černý. "Syntheses of Steroid O-(3-Carboxypropyl)oximes". Collection of Czechoslovak Chemical Communications 62, n.º 3 (1997): 457–70. http://dx.doi.org/10.1135/cccc19970457.

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The syntheses of O-(3-carboxypropyl)oxime derivatives, i.e. bis-homologues of O-(carboxymethyl)oxime derivatives (CMO), derived from dehydroepiandrosterone, testosterone and estradiol are presented. Both the reaction of steroid ketone with O-(3-carboxypropyl)hydroxylamine, and the reaction of sodium salt of steroid oxime with ethyl 4-bromobutyrate were alternatively evaluated, together with some other methods using successive chain lengthening. The compatibility with acetyl and methoxymethyl protecting groups was studied.
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35

Strashnova, S. B., O. V. Avramenko, M. N. Zhuk, O. V. Kovalchukova, P. V. Strashnov y B. E. Zaitsev. "Synthesis and Study of Complexes of Copper(II), Zinc, Cobalt(II) and Nickel(II) with Nitrofluorenylidene-9-Amino(Imino) Derivatives". Chemistry Journal of Moldova 4, n.º 2 (diciembre de 2009): 68–71. http://dx.doi.org/10.19261/cjm.2009.04(2).09.

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The complexes of general formula MCl2∙L1-4∙nH2O (where L1 - N-(2,4,7-trinitrofluorenilidene-9)-p-dimethyl-aminoanilin, L2 - N-(2,4,5,7-tetranitrofluorenilidene-9)-p-dimethylaminoaniline, L3 - N-(2,4,7-trinitrofluorenilidene)-N-(p-dimethylaminophenyl)hydroxylamine, L4 - N-(2,4,5,7-tetranitrofluorenilidene-9)-N-(p-dimethylaminophenyl)-hydroxylamine; M=Cu, Co, Ni, Zn; n= 1-3 have been synthesized and investigated by different methods. Spectral criteria of co-ordination of the molecules L1 –L4 in electronic adsorption spectra were detected.
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36

Ivanov, Maksim A., Elena V. Antonova, Aleksey V. Maksimov, Lyudmila K. Pigusova, Evgenii F. Belanov y Lyudmila A. Aleksandrova. "New N4-Hydroxycytidine Derivatives: Synthesis and Antiviral Activity". Collection of Czechoslovak Chemical Communications 71, n.º 7 (2006): 1099–106. http://dx.doi.org/10.1135/cccc20061099.

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Two series of N4-hydroxycytidine derivatives were synthesized and evaluated as potential antipox virus agents. Acylation of N4-hydroxycytidine (1) with an excess of acyl chloride or imidazolide yielded the corresponding N4-(acyloxy) derivatives. 5'-Phosphonates of 1 were prepared by the reaction of cytidine 5'-phosphonates with aqueous hydroxylamine hydrochloride (pH 6.0). Nucleoside 1 and its N4-(acyloxy) derivatives inhibited replication of pox viruses in cell cultures, N4-(pivaloyloxy)- and N4-(benzoyloxy)cytidines being the most potent. The synthesized 5'-phosphonates were more cytotoxic than the parent nucleoside.
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37

Khomutov, M. A., J. Weisell, M. Hyvönen, T. A. Keinänen, J. Vepsäläinen, L. Alhonen, A. R. Khomutov y S. N. Kochetkov. "Hydroxylamine derivatives for regulation of spermine and spermidine metabolism". Biochemistry (Moscow) 78, n.º 13 (diciembre de 2013): 1431–46. http://dx.doi.org/10.1134/s0006297913130051.

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38

Tan, Fen, Ping Zheng y You-Quan Zou. "Highly Selective Asymmetric Hydrogenation of Oximes to Hydroxylamine Derivatives". Chem 6, n.º 7 (julio de 2020): 1517–19. http://dx.doi.org/10.1016/j.chempr.2020.06.025.

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39

Altenburger, J. M., C. Mioskowski, H. d'Orchymont, D. Schirlin, C. Schalk y C. Tarnus. "Useful hydroxylamine derivatives for the synthesis of hydroxamic acids." Tetrahedron Letters 33, n.º 35 (agosto de 1992): 5055–58. http://dx.doi.org/10.1016/s0040-4039(00)61187-5.

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40

Deepa, Boppana, Natesan Balasubramanian y Karachalacherevu Seetharamiah Nagaraja. "Spectrophotometric Determination of Hydroxylamine and Its Derivatives in Pharmaceuticals". CHEMICAL & PHARMACEUTICAL BULLETIN 52, n.º 12 (2004): 1473–75. http://dx.doi.org/10.1248/cpb.52.1473.

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41

Liang, Guyan, J. Phillip Bowen y James A. Bentley. "Molecular mechanics (MM3) parameterization of hydroxylamine and methyl derivatives". Journal of Computational Chemistry 15, n.º 8 (agosto de 1994): 866–74. http://dx.doi.org/10.1002/jcc.540150808.

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42

Dworak, Claudia, Stefan Kopeinig, Helmuth Hoffmann y Robert Liska. "Photoinitiating monomers based on di- and triacryloylated hydroxylamine derivatives". Journal of Polymer Science Part A: Polymer Chemistry 47, n.º 2 (15 de enero de 2009): 392–403. http://dx.doi.org/10.1002/pola.23156.

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43

S. AL-Rawi, Muna, Huda A. Hassan, Dheefaf F. Hassan y Ismaeel Y. Majeed. "New Series of Substituted Heterocyclics Derived from α , β – Unsaturated Ketone and Their Cytotoxic Activity Tumor Cell Lines". Oriental Journal of Chemistry 34, n.º 6 (10 de noviembre de 2018): 2826–31. http://dx.doi.org/10.13005/ojc/340620.

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The aldol condensation of 2-acetylnaphthalene with 9-anthracene carboxaldehyde afforded α, β-unsaturated keton (1) . New heterocyclic compounds containing: cyclohexenone[2], indazole[3], pyrimidinethion [4], thiazolo fused pyrimidine[5], isoxazoline[6], substituted pyrazoline[7]a-d and pyrimidinone[8] rings system were synthesized from α, β-unsaturated keton[1]. Cyclization of [1] with ethylacetoacetate gave the mentioned heterocycle cyclohexanone [2]. The cyclo condensation of [2] with hydrazine gave the new indazole derivative [3]. furthermore, the reation of [1]with thiourea gives thiopyrmidine derivative [4]. The cyclo condensation of [4] with chloroacetic acid gave the fused rings [5]. Then reacted compound[1] with hydroxylamine to produce isoxazoline [6]. Also the reaction of [1]with hydrazine and hydrazide derivatives to produce pyrazole [7]a-d. All the newly synthesized derivatives[2-7a-d] were characterized via the CHN-S, FT- IR, 1H NMR, and13C NMR (of some of theme). The antibacterial and cytotoxic activities were evaluated for these derivatives[2-7a-d] . The study of antibacterial displayed good to moderate activity and the study of anticancer activity showed that were effective for inhibition of L20 B the mice intestines carcinoma cell line and RD human pelvic rhabdomyosarcoma cell line. Treated.
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44

Černý, Ivan, Tereza Slavíková y Vladimír Pouzar. "Synthesis of (15E)-17β-hydroxy-5α-androstane-3,15-dione 15-[O-(Carboxymethyl)]oxime, New Hapten for Dihydrotestosterone (17β-hydroxy-5α-androstan-3-one)". Collection of Czechoslovak Chemical Communications 62, n.º 10 (1997): 1642–49. http://dx.doi.org/10.1135/cccc19971642.

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Addition of 4-methoxybenzyl alcohol to 3β-hydroxy-5α-androst-15-en-17-one gave the mixture of isomeric 15-(4-methoxyphenyl)methoxy derivatives from which, after acetylation and chromatography, the major 15β isomer was separated. Borohydride reduction gave 17β-hydroxy derivative which was protected as methoxymethyl ether. Oxidative cleavage of protecting group at position 15 and the subsequent Jones oxidation afforded corresponding 15-ketone. Its oximation with O-(carboxymethyl)hydroxylamine, deacetylation and methylation with diazomethane gave protected O-(carboxymethyl)oxime derivative with free hydroxy group at position 3. Its oxidation afforded dihydrotestosterone derivative and successive deprotection of position 17 and of carboxy group led to final (15E)-17β-hydroxy-5α-androstane-3,15-dione 15-[O-(carboxymethyl)]oxime. The title compound was designed as dihydrotestosterone hapten for heterologous radioimmunoassays.
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45

El Mahmoudi, Ayoub, Khalid Karrouchi, Hamza Tachallait y Khalid Bougrin. "Ultrasound Assisted One-Pot Synthesis of Novel 3-(Aryl)-5-((4-(phenyldiazenyl)phenoxy)methyl)isoxazolines in Water". Molbank 2022, n.º 4 (17 de diciembre de 2022): M1529. http://dx.doi.org/10.3390/m1529.

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In this work, we present an efficient one-pot method for the synthesis of three new azo-isoxazoline derivatives (4a–c) from aromatic aldehydes, hydroxylamine hydrochloride and 4-(allyloxy)azobenzene. Thus, the azo-isoxazoline derivatives (4a–c) were synthesized via 1,3-dipolar cycloaddition using sodium dichloroisocyanurate (SDIC) as an eco-friendly and inexpensive oxidizing agent under ultrasound cavitation in water as a green solvent. The desired compounds 4a–c were obtained in high to excellent yields of 75–90%.
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46

Safaei-Ghomi, Javad y Ali Ghasemzadeh. "Synthesis of some 3,5-diarylisoxazoline derivatives in ionic liquids media". Journal of the Serbian Chemical Society 77, n.º 6 (2012): 733–39. http://dx.doi.org/10.2298/jsc110831001s.

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Biologically active isoxazoline derivatives were efficiently synthesized in excellent yields and in less reaction time using mild, effective and environmentally friendly butylmethylimidazolium bromide as solvent and catalyst. By use of this catalyst isoxazoline derivatives are produced via cyclization reaction of chalcone and hydroxylamine hydrochloride in ionic liquids media. The separation of the product was facile and the catalyst could be separated and recycled. Our method is very quick, safe and avoids the use of hazardous and expensive reagents and solvents.
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47

Patil, Sachin V. "SYNTHESIS AND ANTIMICROBIAL EVALUATION OF SOME NEW BENZTHIAZOLE OXIME ETHER DERIVATIVES". Journal of Medical pharmaceutical and allied sciences 11, n.º 6 (15 de noviembre de 2021): 47–50. http://dx.doi.org/10.22270/jmpas.v10i6.1916.

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Some new oxime ether derivatives containing benzthiazole heterocyclic nuclei are synthesized. The reaction of 2-mercapto benzthiazole with α-halo ketones followed by reaction with hydroxylamine gave oxime derivatives which on reaction with alkyl halides viz. ethyl chloride, n-propyl chloride, and n-butyl chloride in absolute ethanol afforded the target compounds 4a-l. The structure of all the synthesized compounds was confirmed by spectroscopic methods like mass and NMR. All compounds after structural confirmation were tested for biological activities.
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48

Kotwal, Urmila, Archana Tiwari y Shweta Choudhary. "Synthesis, Characterization and Antimicrobial Activity of Isoxazoline Derivatives". International Journal of Pharmaceutical Sciences and Medicine 7, n.º 11 (30 de noviembre de 2022): 107–20. http://dx.doi.org/10.47760/ijpsm.2022.v07i11.008.

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In present study isoxazoline derivatives were synthesized and antimicrobial activity of different derivatives were checked with various microbial stain. Various intermediates was synthesized and characterized in between time to time by chromatography using TLC. An isoxazoline series of compounds were synthesized by condensation reaction of phenyl ethyl acetate with substituted benzaldehyde in presence of alcoholic sodium hydroxide to get intermediate phenethyl cinnamate (chalcones), which were further treated with hydroxylamine hydrochloride in presence of sodium hydroxide to get isoxazoline derivatives. The synthesized compounds were characterized on the basis of their spectral (IR) data and evaluated for the antimicrobial activity by using Zone of Inhibition by cup plate method.
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49

Dommaraju, Yuvaraj, Somadrita Borthakur y Dipak Prajapati. "l-Proline-Catalysed One-Pot aza-Diels–Alder Reaction in Water: Regioselective Synthesis of Spiro(isoxazolo[5,4-b]pyridine-5,5′-pyrimidine) Derivatives". Synlett 29, n.º 09 (20 de marzo de 2018): 1195–98. http://dx.doi.org/10.1055/s-0036-1591949.

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A simple and efficient l-proline-catalysed synthesis of spiro(isoxazolo[5,4-b]pyridine-5,5′-pyrimidine) derivatives in water has been accomplished through a pseudo five-component one-pot domino aza-Diels–Alder reaction involving 3-amino crotanonitrile, hydroxylamine hydrochloride, aromatic aldehydes and barbituric acids. The main advantages of the present method are mild reaction conditions, modest purification process involving no chromatographic techniques and high yields. The protocol is a good alternative to prepare spiro derivatives with readily available starting materials, which makes the method highly attractive.
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50

El-Sharkawy, Karam A., Mohammed Al Bratty, Hassan A. Alhazmi y Asim Najmi. "Design, synthesis, and biological activities of novel thiophene, pyrimidine, pyrazole, pyridine, coumarin and isoxazole: Dydrogesterone derivatives as antitumor agents". Open Chemistry 19, n.º 1 (1 de enero de 2021): 322–37. http://dx.doi.org/10.1515/chem-2021-0028.

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Abstract On the basis of our consideration to design and to develop antitumor activities of heterocyclic compound derivatives, especially in fused ring system, we refer to the possibility of the heterocyclic extension of one of the most important steroid compounds used as a medicinal drug. The reaction of dydrogesterone with each of the malononitrile or ethylcyanoacetate containing elemental sulfur afforded thiophene derivatives 1a,b. Also, dydrogesterone was reacted with a mixture of ethylcyanoacetate–hydrazine, ethylcyanoacetae–urea, or ethylcyanoacetate–thiourea to produce pyrazole derivative 4 and pyrimidine derivatives 5a,b. Thienopyrimidine derivatives 2a–d were introduced from the reaction of thiophene derivatives 1a,b with either phenylisothiocyanate or benzoylisothioyanate. Furthermore, compounds 1a,b were directed toward the reaction with ethylcyanoacetate to produce compounds 6a,b, and the last compounds 6a,b were directed toward cyclization to obtain thienopyridine derivatives 7a,b. In addition, compounds 6a,b were subjected to react with different carbonyl compounds, such as salicylaldehyde, cyclopentanone-elemental sulfur, malonaldehyde, and acetylacetone to produce coumarin derivatives 8a,b, fused thiophene derivatives 9a,b, and pyridine derivatives 10a–d. Isooxazole derivatives 12a,b were afforded through the reaction of compounds 6a,b with hydroxylamine hydrochloride. Finally, 2-pyridone derivatives 14a,b were obtained through the reaction of compounds 6a,b with benzoylacetonitrile. Conformation structure of the synthesized compounds was established by applying IR, 1H NMR, 13C NMR, and mass spectrometry, and their antitumor activity was examined. Some compounds showed promising growth inhibitory effects on the three different cell lines.
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