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Sample records for carbazones

  1. Rapid and Efficient Synthesis of Diaryl Carbazones using Microwave Technology

    Institute of Scientific and Technical Information of China (English)

    SHI Lei; PAN Feng; WANG Yu-lu

    2004-01-01

    Diaryl carbazone is an important organic analytical reagent normally prepared by the oxidation of diaryl carbazine, but in literatures' methods, the yields were low and the procedures were trouble1,2. Recently, our laboratory reported some new methods for the preparation of diaryl carbazone from diaryl carbazine3,4. Generally, these methods have drawbacks such as tedious operation3, using large amounts of volatile and poisonous solvent which will pollute the environment inevitably3, long reaction time and complicated oxidation system4. In continuation of our studies on the synthesis of azo compounds, we decided to develop a new method to overcome the limitation.As we know, the application of microwave techniques for organic synthesis has attracted considerable interests in recent years5. Using microwave technology can enhance the selectivity and reactivity, increase the chemical yields and shorten the reaction time6. It has been widely used in a variety of organic reactions7,8. However, the synthesis of diaryl carbazones using microwave has not been reported so far.In this paper, a rapid and efficient synthesis of diaryl carbazones with NaBrO3/H2SO4 as oxidation system using microwave technology is reported for the first time. By this method, in short time (0.5 rmin), we have synthesized ten diaryl carbazones in good yields.In the oxidation study, we found that the acidic condition is necessary in these reactions.This method only needs cheap and easily available oxidants, simple instruments and easy work-up.In conclusion, It is a facile and rapid method for the preparation of diaryl carbazones from diaryl carbazines with NaBrO3/H2SO4.

  2. Convenient and Efficient Solid-state Synthesis of Diaryl Carbazones with NaBrO_3/NaHSO_4·H_2O%NaBrO_3/NaHSO_4 · H_2O 氧化体系简便高效地固态合成二芳基卡巴腙

    Institute of Scientific and Technical Information of China (English)

    时蕾; 潘峰; 张润芳; 李建平

    2009-01-01

    The solid-state synthesis of diaryl carbazones using NaBrO_3/NaHSO_4·H_2O as a oxidation system is reported.Ten diaryl carbazones have been synthesized from diaryl carbazines in good yields under mild conditions.This method is facile,efficient,with no solvent and little pollution.%以NaBrO_3/NaHSO_4 · H_2O 为氧化体系在固态条件下,通过对二芳基卡巴肼的单侧脱氢快速高效合成了十种二芳基卡巴腙.该方法操作简便、产率高、无溶剂、对环境友好.

  3. Novel “turn on” fluorescent sensors based on anthracene and carbazone units for Cu (II) ion in CH{sub 3}CN–H{sub 2}O

    Energy Technology Data Exchange (ETDEWEB)

    Erdemir, Serkan, E-mail: serdemir82@gmail.com; Malkondu, Sait

    2015-02-15

    Two novel anthracene-based receptors containing Schiff base and urea groups (AOC and ATC) were synthesized in one step and full characterized. The optical properties of receptors AOC and ATC towards metal ions were investigated by UV–visible and fluorescence spectroscopy. It was found that both receptors AOC and ATC show highly selectivity towards Cu{sup 2+} over other 17 metal ions in CH{sub 3}CN–H{sub 2}O (9/1, v/v). - Highlights: • Novel fluorescent sensors based on anthracene and carbazide AOC and ATC were synthesized. • The optical properties of AOC and ATC were observed by UV–visible and fluorescence spectroscopy. • AOC and ATC showed highly selective and sensitive to Cu{sup 2+} over other 17 metal ions.

  4. Evaluation of efficacy and effect of application timing of a new herbicide, a.i. propoxy-carbazone + iodosulfuron + mefenpyr on Triticum durum.

    Science.gov (United States)

    Fanigliulo, A; Filì, V; Crescenzi, A

    2012-01-01

    A study was performed from February to May 2010 by Bioagritest according to EPPO guidelines and Principles of Good Experimental Practice (GEP), in the land of Altamura (BA), in the core of Murgia, Apulia Region (Italy). The purpose of the study was to evaluate the efficacy and effect of two different application times of the herbicide SIT90 (propoxycarbazone + iodosulfuron + mefenpyr) on Triticum durum for weeds' control. Sit90 was applied alone or in combination with the herbicide Dicuran (a.i. chlortolorun) in early post-emergence, and in late post emergence once more alone or in combination with the adjuvant Biopower or with the commercial formulate Atlantis WG (mesosulfuron+ iodosulfuron+ mefenpyr) + Biopower. T. durum cultivar was "Iride". The study has given sufficient results on the use of SIT90, in the conditions foreseen by the protocol and in consideration of the present weeds, which represented the species mostly diffused in the Murgia, mainly Avena ludoviciana and Papaver rhoaes. Treatments with the SIT90 alone (even in combination with Chortoluron), applied in early or in late post-emergence, were very ineffective on grass weeds and dicotyledonous, highlighting the importance of the adjuvant Biopower to enhance the expression of the herbicide. In fact, the presence of the adjuvant allowed the expression of a clear and good overall herbicide activity of SIT90 for the control of P. rhoaes and other dicotyledonous, but also a discrete activity against grasses. More reliable was the treatment with SIT90 mixed with Atlantis, against the entire community of grass weeds and on F. officinalis. The performance of all the treatments was insufficient on P. rhoaes, because of the clear resistance shown by the weed.

  5. {sup 64} Cu-pyruvaldehide-bis-(N{sup 4} methyl-thio semi-carbazone) - Cu-PTSM as brain tracer for positron emission tomography; Cu-piruvaldehido-bis-(N{sup 4} metiltiosemicarbazona) o Cu-PSTM como trazador cerebral para tomografia por emision de positrones

    Energy Technology Data Exchange (ETDEWEB)

    Arguelles, M.G.; Lago Fernandez, J.L.; Casale, G.A.; Torres, E.A. [Comision Nacional de Energia Atomica, Buenos Aires (Argentina)

    1995-12-31

    Synthesis of Pyruvaldehide-bis-(N{sup 4}-methyl-thio semicarbazone) PTSM used for medical investigation and diagnosis has been carried out in our Radiopharmaceutical Division in Centro Atomico Ezeiza. PTSM has been obtained introducing modifications to a previous synthesis published by H.G. Petering TLC, HPLC and IR, UV spectrum controls have been performed. Cu-64 can be obtained by the Cu-63 (n, {gamma}) and Zn-64 (n,p) reactions. This last reaction has been chosen for the production in the RA-3 reactor since it leads to Cu-64 of high specific activity. Two different assays have been performed to obtain the chelate PTSM-Cu-64. The first one has beer carried out by buffering the Cu-64 solution to pH 3-4; adding the PTSM solution in ethanol. The second assay has been carried out by buffering the Cu-64 solution with sodium acetate 3 M and adding 100 {mu}l of PTSM solution in ethanol. The chelate thus obtained is purified in Sepak C-18. Radiochemical purity has been tested by thin layer chromatography. Biodistribution studies have been carried on NIH mice and Wistar rats showing a brain uptake of 4%, 30 minutes after injection. Thus, FTMS-Cu-64 proves to be a good brain diagnosis agent. (author). 7 refs., 3 figs.

  6. Dose escalation to high-risk sub-volumes based on non-invasive imaging of hypoxia and glycolytic activity in canine solid tumors

    DEFF Research Database (Denmark)

    Clausen, Malene M.; Hansen, Anders Elias; af Rosenschold, Per Munck;

    2013-01-01

    Introduction: Glycolytic activity and hypoxia are associated with poor prognosis and radiation resistance. Including both the tumor uptake of 2-deoxy-2-[18 F]-fluorodeoxyglucose (FDG) and the proposed hypoxia tracer copper(II)diacetyl-bis(N4)-methylsemithio-carbazone (Cu-ATSM) in targeted therapy...

  7. Injectable hyaluronic acid hydrogel for 19F magnetic resonance imaging

    NARCIS (Netherlands)

    Yang, X.; Sun, Y.; Kootala, S.; Hilborn, J.; Heerschap, A.; Ossipov, D.

    2014-01-01

    We report on a 19F labeled injectable hyaluronic acid (HA) hydrogel that can be monitored by both 1H and 19F MR imaging. The HA based hydrogel formed via carbazone reaction can be obtained within a minute by simple mixing of HA-carbazate and HA-aldehyde derivatized polymers. 19F contrast agent was l

  8. Comparison of sampling methods for radiocarbon dating of carbonyls in air samples via accelerator mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Schindler, Matthias, E-mail: matthias.schindler@physik.uni-erlangen.de; Kretschmer, Wolfgang; Scharf, Andreas; Tschekalinskij, Alexander

    2016-05-15

    Three new methods to sample and prepare various carbonyl compounds for radiocarbon measurements were developed and tested. Two of these procedures utilized the Strecker synthetic method to form amino acids from carbonyl compounds with either sodium cyanide or trimethylsilyl cyanide. The third procedure used semicarbazide to form crystalline carbazones with the carbonyl compounds. The resulting amino acids and semicarbazones were then separated and purified using thin layer chromatography. The separated compounds were then combusted to CO{sub 2} and reduced to graphite to determine {sup 14}C content by accelerator mass spectrometry (AMS). All of these methods were also compared with the standard carbonyl compound sampling method wherein a compound is derivatized with 2,4-dinitrophenylhydrazine and then separated by high-performance liquid chromatography (HPLC).

  9. Comparison of sampling methods for radiocarbon dating of carbonyls in air samples via accelerator mass spectrometry

    Science.gov (United States)

    Schindler, Matthias; Kretschmer, Wolfgang; Scharf, Andreas; Tschekalinskij, Alexander

    2016-05-01

    Three new methods to sample and prepare various carbonyl compounds for radiocarbon measurements were developed and tested. Two of these procedures utilized the Strecker synthetic method to form amino acids from carbonyl compounds with either sodium cyanide or trimethylsilyl cyanide. The third procedure used semicarbazide to form crystalline carbazones with the carbonyl compounds. The resulting amino acids and semicarbazones were then separated and purified using thin layer chromatography. The separated compounds were then combusted to CO2 and reduced to graphite to determine 14C content by accelerator mass spectrometry (AMS). All of these methods were also compared with the standard carbonyl compound sampling method wherein a compound is derivatized with 2,4-dinitrophenylhydrazine and then separated by high-performance liquid chromatography (HPLC).

  10. Synthesis of novel coumarin appended bis(formylpyrazole) derivatives: Studies on their antimicrobial and antioxidant activities.

    Science.gov (United States)

    Nagamallu, Renuka; Srinivasan, Bharath; Ningappa, Mylarappa B; Kariyappa, Ajay Kumar

    2016-01-15

    A series of novel coumarin pyrazole hybrids of biological interest were synthesized from the hydrazones, carbazones and thiocarbazones via Vilsmeier Haack formylation reaction. These intermediates and formyl pyrazoles were evaluated for antimicrobial and antioxidant activities. Among the series, compounds 6g and 6h showed excellent antimicrobial activity against different bacterial and fungal strains and compounds 7g, 7h were found to be potent antioxidant agents in both DPPH and hydroxyl radical scavenging assays. Further, detailed quantitative structure-activity relationship (QSAR) analysis indicated the molecular parameters that contribute to increased potency of inhibition. The above findings would further encourage our understanding in employing coumarin pyrazole hybrids as potential antibiotic agents for treating infections caused by pathogenic microbes and fungi. Further, it also paves the way for exploration of these compounds as potential therapeutic agents to treat conditions arising because of excessive oxidative damage.

  11. Preparation of modified magnetic nanoparticles as a sorbent for the preconcentration and determination of cadmium ions in food and environmental water samples prior to flame atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Mirabi, Ali; Dalirandeh, Zeinab [Department of Chemistry, Qaemshahr Branch, Islamic Azad University, Qaemshahr (Iran, Islamic Republic of); Rad, Ali Shokuhi, E-mail: a.shokuhi@qaemshahriau.ac.ir [Department of Chemical Engineering, Qaemshahr Branch, Islamic Azad University, Qaemshahr (Iran, Islamic Republic of)

    2015-05-01

    A new method has been developed for the separation/preconcentration of trace level cadmium ions using diphenyl carbazone/sodium dodecyl sulfate immobilized on magnetic nanoparticle Fe{sub 3}O{sub 4} as a new sorbent SPE and their determination by flame atomic absorption spectrometry (FAAS). Synthesized nanoparticle was characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM). Various influencing parameters on the separation and preconcentration of trace level cadmium ions such as, pH value, amount of nanoparticles, amount of diphenyl carbazone, condition of eluting solution, the effects of matrix ions were examined. The cadmium ions can be eluted from the modified magnetic nanoparticle using 1 mol L{sup −1} HCl as a desorption reagent. The detection limit of this method for cadmium was 3.71 ng ml{sup −1} and the R.S.D. was 0.503% (n=6). The advantages of this new method include rapidity, easy preparation of sorbents and a high concentration factor. The proposed method has been applied to the determination of Cd ions at trace levels in real samples such as, green tea, rice, tobacco, carrot, lettuce, ginseng, spice, tap water, river water, sea water with satisfactory results. - Highlights: • MNPs method is economical, simple, rapid and sensitive for trace analysis of Cd. • High preconcentration factor was obtained easily through this method. • A detection limit at ng mL{sup −1} level was achieved with 100.0 mL of sample. • This method provides good repeatability and extraction efficiency in a short time.

  12. Confirmation of hydroxyl radicals (•OH) generated in the presence of TiO2 supported on AC under microwave irradiation.

    Science.gov (United States)

    Zhang, Zhaohong; Yu, Fengyang; Huang, Lirong; Jiatieli, Jianaerguli; Li, Yuanyuan; Song, Lijun; Yu, Ning; Dionysiou, Dionysios D

    2014-08-15

    In order to study the degradation mechanism of technology of microwave (MW) combined with TiO2 supported on activated carbon (TiO2/AC), the reactive oxygen species (ROS) was explored through oxidation of 1,5-diphenyl carbazide (DPCI) to 1,5-diphenyl carbazone (DPCO). Furthermore, 2,6-di-tert-butyl-4-methylphenol (BHT), Mannitol (MT) and Vitamin C (VC) were used as radical scavengers to confirm the generation of the hydroxyl radicals ((•)OH). In addition, the influence of some parameters such as TiO2 mass ratio content, irradiation time, material dose, DPCI concentration and MW power on the determination of (•)OH were examined. The results showed that the (•)OH could be generated under MW combined with loaded TiO2/AC. Also, anatase TiO2/AC can generate more (•)OH radicals than rutile TiO2/AC under MW irradiation. This work would provide new mechanistic insights on the enhanced degradation effect of organic pollutants in water using the supported TiO2/AC coupled with MW technology.

  13. Oxidation-extraction spectrometry of reactive oxygen species (ROS) generated by chlorophyllin magnesium (Chl-Mg) under ultrasonic irradiation.

    Science.gov (United States)

    Guo, Yuwei; Cheng, Chunping; Wang, Jun; Jin, Xudong; Liu, Bin; Wang, Zhiqiu; Gao, Jingqun; Kang, Pingli

    2011-09-01

    In order to examine the mechanism and process of sonodynamic reaction, the chlorophyllin magnesium (Chl-Mg) acting as a sonosensitizer was irradiated by ultrasound, and the generation of reactive oxygen species (ROS) were detected by the method of oxidation-extraction spectrometry (OES). That is, under ultrasonic irradiation in the presence of Chl-Mg, the 1,5-diphenyl carbazide (DPCI) is oxidized by generated ROS into 1,5-diphenyl carbazone (DPCO), which can be extracted by mixed organic solvent and display a obvious visible absorption at 563 nm wavelength. Besides, the generation conditions of ROS were also reviewed. The results demonstrated that the quantities of generated ROS increased with the increase of ultrasonic irradiation time, Chl-Mg concentration and DPCI concentration. Finally, several radical scavengers (l-Histidine (His), 2,6-Di-tert-butyl-methylphenol (BHT) and Vitamin C (VC)) were used to determine the kind of the generated ROS. It was found that at least the hydroxyl radical (OH) and singlet oxygen (1O2) were generated in the presence of Chl-Mg under ultrasonic irradiation. It is wish that this paper might offer some valuable references for the study on the mechanism of SDT and the application of Chl-Mg in tumor treatment.

  14. Detection and comparison of reactive oxygen species (ROS) generated by chlorophyllin metal (Fe, Mg and Cu) complexes under ultrasonic and visible-light irradiation.

    Science.gov (United States)

    Wang, Jun; Guo, Yuwei; Gao, Jingqun; Jin, Xudong; Wang, Zhiqiu; Wang, Baoxin; Li, Kai; Li, Ying

    2011-09-01

    In this paper, in order to examine the mechanisms of sonodynamic and photodynamic reactions, the chlorophyllin metal (Chl-M (M=Fe, Mg and Cu)) complexes were irradiated by ultrasound (US) and visible-light (VL), respectively, and the generation of reactive oxygen species (ROS) were detected by the method of Oxidation-Extraction Spectrometry (OES). That is, the 1,5-diphenyl carbazide (DPCI) is oxidized by the generated ROS into 1,5-diphenyl carbazone (DPCO), which can display a various visible absorption around 563 nm wavelength. Besides, some influence parameters on the generation of ROS were also reviewed. The results demonstrated an apparent synergistic effect of Chl-M and ultrasonic or visible-light irradiation for the generation of ROS. Moreover, the quantities of generated ROS increase with the increase of (ultrasonic or visible-light) irradiation time and Chl-M (M=Fe, Mg and Cu) concentration. Finally, several quenchers were used to determine the kind of the generated ROS. It is wished that this paper might offer some valuable references for the study on the sonodynamic therapy (SDT) and photodynamic therapy (PDT) mechanisms and the application of Chl-M in tumor treatment.

  15. Confirmation of hydroxyl radicals ({sup •} OH) generated in the presence of TiO{sub 2} supported on AC under microwave irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhaohong, E-mail: lnuhjhx@163.com [School of Environmental Science, Liaoning University, Shenyang 110036 (China); Yu, Fengyang; Huang, Lirong; Jiatieli, Jianaerguli; Li, Yuanyuan; Song, Lijun [School of Environmental Science, Liaoning University, Shenyang 110036 (China); Yu, Ning [Experiment Center of Environmental Monitoring of Liaoning Province, Shenyang 110161 (China); Dionysiou, Dionysios D., E-mail: dionysios.d.dionysiou@uc.edu [Environmental Engineering and Science Program, University of Cincinnati, Cincinnati, OH 45221-0012 (United States)

    2014-08-15

    Graphical abstract: - Highlights: • Generation of {sup •} OH in MW integrated with loaded TiO{sub 2}/AC system was confirmed. • Confirmation of {sup •} OH was conducted using radical scavenger such as BHT, MT and VC. • More {sup •} OH was formed using anatase TiO{sub 2}/AC than rutile TiO{sub 2}/AC under MW irradiation. • Effect of mass ratio, irradiation time, catalyst dose and DPCI on {sup •} OH was studied. - Abstract: In order to study the degradation mechanism of technology of microwave (MW) combined with TiO{sub 2} supported on activated carbon (TiO{sub 2}/AC), the reactive oxygen species (ROS) was explored through oxidation of 1,5-diphenyl carbazide (DPCI) to 1,5-diphenyl carbazone (DPCO). Furthermore, 2,6-di-tert-butyl-4-methylphenol (BHT), Mannitol (MT) and Vitamin C (VC) were used as radical scavengers to confirm the generation of the hydroxyl radicals ({sup •} OH). In addition, the influence of some parameters such as TiO{sub 2} mass ratio content, irradiation time, material dose, DPCI concentration and MW power on the determination of {sup •} OH were examined. The results showed that the {sup •} OH could be generated under MW combined with loaded TiO{sub 2}/AC. Also, anatase TiO{sub 2}/AC can generate more {sup •} OH radicals than rutile TiO{sub 2}/AC under MW irradiation. This work would provide new mechanistic insights on the enhanced degradation effect of organic pollutants in water using the supported TiO{sub 2}/AC coupled with MW technology.