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Search Results: 1 - 10 of 253029 matches for " +((fullName:european shortName:european) (fullName:journal shortName:journal) (fullName:chemistry shortName:chemistry)) "

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An efficient route for the synthesis of some monoazo disperse dyes derived from nicotinic acid derivatives  [cached]
Abdulaziz Alnajjar,Marzouq Alsaiedi,Morsy Ahmed El-Apasery
European Journal of Chemistry , 2013, DOI: 10.5155/eurjchem.4.1.53-57.733
Abstract: Ethyl 2-amino-3-cyano-4-phenylnicotinates (8), could be readily synthesized via reacting ethyl propiolate with benzylidenemalononitrile in the presence of L-proline as a catalyst and subsequent rearrangement of the so formed 2-aminopyran (7), with acetic acid in the presence of ammonium acetate. A series of 2-amino and 2-hydroxyarylazonicotinates monoazo disperse dyes (12a-c), were prepared in a good yields via condensation of arylhydrazonals (11a-c), with active methylene nitriles. The compound 9 was also characterized by single crystal X-ray diffraction studies. Crystal data for compound 9, C15H18O6 (M = 294.29): hexagonal, space group P65 (no. 170), a = 11.3311(5) , c = 19.5375(10) , V = 2172.42(18) 3, Z = 6, T = 296(2) K, μ(MoKα) = 0.879 mm-1, Dcalc = 1.350 g/mm3, 4546 reflections measured (9.02 ≤ 2Θ ≤ 132.96), 2271 unique (Rint = 0.0921) which were used in all calculations. The final R1 was 0.0686 (>2σ(I)) and wR2 was 0.1691 (all data).
Validation of analysis method for determining ketoprofen concentration in pharmaceutical dosage form using high performance liquid chromatography  [cached]
Tadjuddin Naid,Wahyu Rizandi Syukur,Amran Ilyas,Seniwati Dali
European Journal of Chemistry , 2013, DOI: 10.5155/eurjchem.4.1.58-60.678
Abstract: The study was conducted with the purpose to develop and validate a high performance liquid chromatography method with UV detector to determine ketoprofen content in tablet preparation using ethanol-phosphate buffer (pH = 6.0, 80:20, v:v). The method was validated toward parameters of accuracy, precision, linearity, selectivity, LOD and LOQ. The results obtained fulfill the validation requirement of the ketoprofen tablet in the form of LOD = 0.5302 ppm and LOQ = 1.7676 ppm.
Guide for Authors  [cached]
Hakan Arslan
European Journal of Chemistry , 2010, DOI: 10.5155/eurjchem.1.1.iii-v.25
Abstract: Guide for Authors
Decolorization of methylene blue by new fungus: Trichaptum biforme and decolorization of three synthetic dyes by Trametes hirsuta and Trametes gibbosa  [cached]
Hossein Eshghi,Zahra Alishahi,Mahmood Zokaei,Aboulfazl Daroodi
European Journal of Chemistry , 2011, DOI: 10.5155/eurjchem.2.4.463-468.425
Abstract: In order to screen dye decolorization by Trametes hirsuta, Trametes gibbosa and new fungus Trichaptum biforme, Methylene Blue (MB), Methyl Green (MG) and Reactive Black 5 (RB5) were studied in Broth culture at concentrations of 25, 50 and 70 ppm. Decolorization of these three kind dyes by T. hirsuta decreased by increasing of concentration. Decolorization of RB5 by T. hirsuta was examined in two different medium contains of Mn2+ or veratryl alcohol (VA), as activators. At the presence of laccase activator (VA), RB5 was decolorized 91% at concentration of 70 ppm, and in the medium contains of MnP activator (Mn2+), dye was decolorized less than 50% at same concentration. Decolorization of RB5 by T. hirsuta was more than decolorization of dye at the presence of MnP activator (Mn2+). T. gibbosa decolorized MB, MG and RB5 more than 80% in the presence of MnP activator. Decolorization of the three kind dyes by T. gibbosa, was independent of concentration. T. gibbosa decolorized different dyes during 20 days and T. hirsuta did it during 32 days, this is due higher potential of decolorization of synthetic dyes for T. gibbosa than T. hirsuta. Decolorization of MB by new fungus T. biforme was studied in two medium contains of MnP activator and laccase activator. Rate of decolorization in the presence of MnP activator was more than decolorization in the presence of laccase activator. Decolorization of MB by new fungus T. biforme was higher than decolorization of MB by two other fungi.
Synthesis, antifungal activity and semi-empirical AM1-MO calculations of some new 4-oxo-4H-chromene derivatives  [cached]
Hafez Mohamed El-Shaaer,Salah Abdel-Ghaffar Abdel-Aziz,Faten Ismail Hanafy,Tarik El-Sayed Ali
European Journal of Chemistry , 2011, DOI: 10.5155/eurjchem.2.2.158-162.381
Abstract: Some new antifungal agents have been prepared through reaction of 4-oxo-4H-chromene-3-carbaldehydes (1a,b) with some active primary amines (2a-e) and amides/thioamides (6a-d) in different conditions. Structures of the products were established on the basis of elemental analysis, IR, 1H NMR, mass spectra and semi-empirical AM1-MO calculations.
Modeling of cation diffusion in bifunctional polymers based on cis-tetraphenylcalix[4]resorcinarene  [cached]
Heinrich Naumovich Altshuler,Olga Heinrichovna Altshuler
European Journal of Chemistry , 2011, DOI: 10.5155/eurjchem.2.1.14-17.297
Abstract: In this study, we report that interaction of the network functional polymers based on cis-tetraphenylcalix[4]resorcinarene with aqueous solutions of electrolytes is controlled by diffusion of ions in a polymeric phase. The nanoreactor effect consisting in sufficiently high rate increase of a cation diffusion flux in bifunctional polymers containing sulfonic acid and phenol ionogenic groups has been found. For steady and non-steady states the solutions of the fundamental differential equation of cation diffusion in bifunctional polymers by means of the spherical layer model are obtained for a variety of initial and boundary conditions with constant diffusion coefficient. The proposed mathematical model explains the nanoreactor effect in bifunctional polymers.
Selective iodination of 2-acetyl-1-naphthol using iodine and iodic acid under solvent-free grinding technique  [cached]
Sainath Zangade,Shyam Mokle,Avinash Shinde,Yeshwant Vibhute
European Journal of Chemistry , 2012, DOI: 10.5155/eurjchem.3.3.314-315.641
Abstract: Selective electrophilic iodination of 2-acetyl-1-naphthol was achieved using iodine and iodic acid in combination with grinding at room temperature under solvent-free conditions to yield 1-(1-hydroxy-4-iodo-naphthalen-2-yl)-ethanone. Grinding mode of reactions has not only of interest from economical point of view, in many cases they also offer considerable advantages in terms of yield, mild reaction conditions, selectivity and simplicity of reaction procedure.
Synthesis and reactions of 3-aminotetrachloroquinazolin-2,4-dione  [cached]
Mamdouh Adly Hassan,Ahmed Mohamed Mosalem Younes,Mohamed Mobark Taha,Abou-Bakr Haredy Abdel-Monsef
European Journal of Chemistry , 2011, DOI: 10.5155/eurjchem.2.4.514-518.479
Abstract: N-phenylsulphonyloxytetrachlorophthalimide was obtained by treatment of N-hydroxy tetrachlorophthalimide with benzenesulphonyl chloride. Also, the titled compound 3 was obtained by reaction of compound 2 with hydrazine hydrate via Lossen rearrangement. Compound 3 used as starting material for the synthesis of new pyrimidine and quinazolinedione derivatives containing four chlorine atoms which have pharmacological activity.
Synthesis, characterization and luminescence properties of long afterglow Phosphor Ba4Al14O25:Eu,Dy  [cached]
Fatih Mehmet Emen,Nevzat Külcü,Ahmet Necmeddin Yaz?c?
European Journal of Chemistry , 2010, DOI: 10.5155/eurjchem.1.1.28-32.8
Abstract: Long persistent afterglow phosphor, Ba4Al14O25:Eu2+,Dy3+ was prepared at high temperature by a solid state reaction in a weak reductive atmosphere. The crystal structure of Ba4Al14O25:Eu2+,Dy3+ has been determined as an orthorhombic Pmmm space group with a=18.200(6) , b=16.923(6) , c=5.131(21) , V=1580.3(9) 3 and Z=8. The reflectance measurement was obtained by using the Diffuse Reflectance Spectrophotometer and the band gap energy of the undoped host phase of Ba4Al14O25 was calculated by using Kubelka-Munk treatment on the diffuse reflectance spectra, and found to be 4.72 eV. The excitation and emission peaks are broad bands and the main emission peak at 520 nm with shoulder at 496 nm belongs to the intrinsic defect of the host and 4f65d1→4f7 transition of Eu2+, respectively. The afterglow decay curve implied that this phosphor contains fast and slow-decay processes. The thermoluminescence glow curve showed one dominant glow peak observed at 50 oC and two weak glow peaks at around 140 oC and 220 oC which are related to the defects at different trap depths.
Synthesis of new 4,6-disubstituted-1,3-5-triazin-2-yloxy esters and N-hydroxyamides  [cached]
Svetlana Mikhaylichenko,Olga Kvak,Shadi Dalili,Vladimir Zaplishny
European Journal of Chemistry , 2010, DOI: 10.5155/eurjchem.1.4.302-306.185
Abstract: A convenient method for synthesis of new sym-triazine ester and hydroxamate derivatives has been developed. Various reaction conditions were studied and optimized, and a series of new 1,3,5-triazine based esters and N-hydroxyamides were obtained with good yields (38-80%). The reaction between oxo-derivatives of 4,6-disubstituted-1,3,5-triazines and halogenated carboxylic esters derivatives using Cs2CO3 as a catalyst was found to be the most convenient method for 4,6-disubstituted-1,3,5-triazine-2-yloxy esters synthesis. These 1,3,5-triazin based esters served as precursors for the synthesis of 4,6-disubstituted-1,3,5-triazin-2-yloxy-N-hydroxybutanamides using solution of hydroxylamine hydrochloride in dry methanol and KOH at room temperature. Structures of the newly synthesized compounds were obtained by 1H NMR, 13C NMR, MS, IR spectral data and elemental analysis.
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