revisiting the synthesis of 7 aminocephalosporanic acid
báo cáo hóa học:" Minireview: Transaminases for the synthesis of enantiopure beta-amino acids" doc
Ngày tải lên :
21/06/2014, 17:20
... for the synthesis of optically pure βamino acids These pyridoxal 5’-dependent enzymes catalyze the transfer of an amino group from a donor substrate to an acceptor, thus enabling the synthesis of ... Streptomyces griseus The β-amino acid moieties are highlighted in grey (b) Comparison of the backbones of α-, β3- and β2-peptides Fig Schematic reaction scheme of the synthesis of β-amino acids catalyzed ... changed marginally - 17 - Conclusions and future areas of research TAs possess a great potential for the enzymatic synthesis of enantiopure β-amino acids as these enzymes offer the possibility to...
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Guanidine catalyzed enantioselective mannich reaction towards the synthesis of amino acids
Ngày tải lên :
10/09/2015, 08:31
... 67 89 65 93 61 78 66 71 57 16 63 EVE 72 h Yield (%) ee (%) 57 88 41 79 61 82 51 90 36 86 13 73 97 75 43 79 23 78 Mannich Reaction As potential precursors for -lactams, various strategies for the ... TOWARDS THE SYNTHESIS OF -AMINO ACIDS PAN YUANHANG (BSc., Zhejiang University) A THESIS SUBMITTED FOR THE DEGREE OF DOCTOR OF PHILOSOPHY DEPARTMENT OF CHEMISTRY NATIONAL UNIVERSITY OF SINGAPORE ... incomplete Due to the similar polarity of 82 and 83, it was difficult to separate them Because of these two facts, the yield of 83 was about 30 -70 % 30 Chapter 2.2.2 Synthesis of N-Sulfonyl Imines...
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Báo cáo khoa học: Arabidopsis thaliana CYP77A4 is the first cytochrome P450 able to catalyze the epoxidation of free fatty acids in plants potx
Ngày tải lên :
07/03/2014, 03:20
... derivatives of the epoxides of linoleic acid produced by CYP77A4 Fig S6 Fragmentation patterns of the derivatives of the epoxides of linolenic acid produced by CYP77A4 FEBS Journal 276 (2009) 71 9 73 5 ... of the enantiomers CYP77A4, an epoxy fatty acid- forming enzyme Metabolism of a-linolenic acid by CYP77A4 The incubation of a-linolenic acid (C18:3) with microsomes from yeast expressing CYP77A4 ... plot of oxidation of fatty acids by CYP77A4 Fig S4 Fragmentation patterns of the derivatives of hydroxyoleic and epoxystearic acids produced by CYP77A4 Fig S5 Fragmentation patterns of the derivatives...
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Báo cáo khoa học: Mycobacterium tuberculosis possesses a functional enzyme for the synthesis of vitamin C, L-gulono-1,4-lactone dehydrogenase doc
Ngày tải lên :
07/03/2014, 12:20
... site in the junction between the GST tag and the Rv 177 1 sequence Upon h of induction of the pDEST15_Rv 177 1 E coli strain with isopropyl-b-dthiogalactopyranoside (IPTG) at 37 °C, the yield of the ... similar to the M tuberculosis Rv 177 1 sequence is present Other mycobacteria apparently not contain sequences homologous to the Rv 177 1 protein The predicted molecular mass of the Rv 177 1 protein ... which catalyzes the last step in the biosynthesis of erythroascorbic acid in yeasts, resulted in attenuated virulence of the Candida albicans mutant [42] If synthesized by the Rv 177 1 l-gulono1,4-lactone...
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Báo cáo khoa học: Reconstruction ofde novopathway for synthesis of UDP-glucuronic acid and UDP-xylose from intrinsic UDP-glucose inSaccharomyces cerevisiae pptx
Ngày tải lên :
07/03/2014, 12:20
... precursors for synthesis of the cell wall [13,15,16] However, it has been impossible to obtain direct confirmation of the hypothesis on the basis of the size of the UDP pool in vivo, because of the complexity ... in the maintenance of the cytoplasmic pool of UDP-Glc in vivo The quantitative analysis of UDP-sugars reveals that the amount of UDP-Glc in the TOY1 strain was FEBS Journal 273 (2006) 2645–26 57 ... because UDP-GlcA or UDP-Xyl synthesized in those organisms are further converted to the other UDP-sugars or used in the synthesis of oligosaccharides and polysaccharides of the cell wall In S cerevisiae,...
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Báo cáo Y học: Guanosine diphosphate-4-keto-6-deoxy-D-mannose reductase in the pathway for the synthesis of GDP-6-deoxy-D-talose in Actinobacillus actinomycetemcomitans potx
Ngày tải lên :
17/03/2014, 10:20
... [20] The GC contents of the genes essential for SPA biosynthesis in A actinomycetemcomitans SUNYaB 75 are lower than the average GC content ( 47. 8%) of the genes flanking them The GC contents of ... 48.0% [43] The GC content of the region essential for the biosynthesis of SPA in the other serotype strains (b–e) of A actinomycetemcomitans is also lower than the average GC content of these genes ... characterized the gene clusters responsible for the biosynthesis of SPAs of A actinomycetemcomitans serotypes a, b, c, d, and e [23,29,34–36] The gene cluster associated with the synthesis of SPA in...
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facile route to the synthesis of porous - fe2o3 nanorods
Ngày tải lên :
19/03/2014, 16:48
... progresses, the growth proceeds along the active sites, resulting in the formation of elongated nanostructures in the form of rods We believe that because of the electrostatic interaction of the iron ... removal of the template by solvent extraction and calcinations, the FE-SEM micrograph (Fig 2B) reveals the remarkable effect on the macroscopic structure of the nanorods The presence of nanorods ... micelle of the surfactant helps in the morphology selectivity during the growth process The magnetic properties of the porous ␣-Fe2 O3 nanorods were further investigated using SQUID To investigate the...
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solvothermal reactions- an original route for the synthesis of novel materials
Ngày tải lên :
20/03/2014, 13:08
... appropriated to that of the target-materials In addition, the concentration of the precursors seems to play a role on the control of the shape of nanocrystallites resulting of a solvothermal process ... in the solvothermal reactions The selection of the solvent plays a key-role through the control of the chemical mechanisms leading to the targetmaterial The reaction mechanisms induce, during the ... are involved during the solvothermal process: Hg2+?2Hg2+ + 2e– and Te + 2 e–?Te2– Then the reaction, with the precursor Rb2Te, leads to the synthesis of Rb2Hg3Te4 The use of FeCl2 as additive...
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the application of ultrasound radiation to the synthesis of nanocrystalline
Ngày tải lên :
20/03/2014, 13:11
... XRD by the Scherrer equation, are presented in Table 4.1 Reaction mechanisms of metal oxide particles in non-aqueous synthesis This section will discuss the organic side of the synthesis of inorganic ... with the precursor to form metal–oxygen–metal groups (Scheme 2, Eq 2) The combination of these two equations leads to the elimination of R–X and H–X The other possibility is the elimination of ... current anionic solvothermal reaction is endothermic, and thus thermodynamic calculations were carried out DH0 : the enthalpy of the formation of the synthesis of titanium f oxide from benzyl alcohol...
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Báo cáo khoa học: On the reaction of D-amino acid oxidase with dioxygen: O2 diffusion pathways and enhancement of reactivity docx
Ngày tải lên :
28/03/2014, 23:20
... from the isoalloxazine ring of the flavin), the redox properties of the W50P variant are also significantly altered, for example there is no stabilization of the flavin anionic semiquinone and the ... cooperativity with respect to the other substrate In fact, this unusual behavior of I225V DAAO is lost in the presence of the imino acid product The reaction of the reduced enzyme forms with ... monitoring the time course of the flavin oxidation state based on its absorbance at 455 nm [6 ,7] at pH 8.5 and 15 °C (B,C) Tertiary plots of the reciprocal of the y intercepts (B) and the x intercepts...
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Báo cáo khoa học: The role of Ureaplasma nucleoside monophosphate kinases in the synthesis of nucleoside triphosphates potx
Ngày tải lên :
30/03/2014, 08:20
... volume of 20 lL The reaction was initiated by the addition the enzyme (100 ngÆreaction)1 for the determination of NTP synthesis rates and 0.5–1 ngÆreaction)1 for the determination of NDP synthesis ... levels for DNA synthesis could be the reason Mollicutes lack the de novo synthesis of purine and pyrimidine bases and have to rely on salvage path1988 ways for the biosynthesis of nucleotides ... [3H]dCDP synthesis and two-fold lower for [3H]dCTP synthesis (Table 1) Nucleoside triphosphate synthesis catalyzed by UMPK Using [3H]UMP as substrate, the rates of [3H]UDP and [3H]UTP synthesis...
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Báo cáo khoa học: Revisiting the prediction of protein function at CASP6 potx
Ngày tải lên :
30/03/2014, 10:20
... CM EG IP UP IP IP UP UP UP-IP 374 6, 8135, 3 676 3 676 , 5488 1 678 7, 3824 476 6, 1 676 5, 875 7, 8168, 1 674 1, 1 674 0, 3824 5198 3 677 , 3 676 , 5488 3862, 16491 8168, 1 674 1, 1 674 0, 3824 16 15 12 10 12 12 10 ... contribute to the consensus Target GOF Function NP N(comb) T0212 T0214 T0216 T0222 T02 27 T0232 T02 37 T0249 5515 3 677 82 37 50825 3 677 4364 379 3 5515 30528 370 0 3 677 2 2 3 1 2 T0251 T0 275 5489 5524 ... from the other CASP categories because, at the end of the experiment, the function of the target protein is likely still to be unknown However, the analysis of the submitted predictions made the...
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a novel method for the synthesis of titania nanotubes using
Ngày tải lên :
05/05/2014, 15:26
... explained by the faster mobility of the F− ions into the nanotubular reaction channel and effusion of the [TiF6 ]2− ions from the channel It is well known that the cavitation effect of ultrasonication ... magnetic stirring The saturation of current with time indicates the development of repassivation, the saturation of nanotube formation These results are in line with the findings of our FESEM studies ... until repassivation occurs [ 17, 19] Nanotube formation goes through the diffusion of F− ions and simultaneous effusion of the [TiF6 ]2− ions The faster rate of formation of TiO2 nanotubes using ultrasonic...
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a novel method for the synthesis of cao nanoparticle
Ngày tải lên :
06/05/2014, 08:55
... These substances also control both towards the toxicants makes them the potential the reduction rate of metal ions and the materials for the decomposition applications agglomeration process of ... reaction of the 2-CEPS with CaO program for GC: The carrier gas was helium nanoparticles with a flow rate of mL.min-1 The initial and For this purpose, 10 μL of 2-CEPS, mL of final temperature of the ... remediation the reactions are analogous to their solution agent, adsorbent, etc [33-36] In the present behavior Recent investigations have explored work, the synthesis of CaO nanoparticles by the promising...
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solgel based hydrothermal method for the synthesis of 3d flowerlike zno microstructures
Ngày tải lên :
06/05/2014, 13:26
... hydrothermal synthesis, growth mechanism, and properties of ZnO three-dimensional structures, New J Chem 34 (2010) 73 2 -73 7 15 [ 27] F Xu, Y.N Lu, Y Xie, Y.F Liu, Synthesis and Photoluminescence of ... concentration of OH is present in the aqueous medium Following the decrease in the concentration of Zn(OH)42 due to the initial fast nucleation of ZnO, the absorption of OH ions on the positively ... investigated Herein, we report the further use of this facile, low-cost, green solgel-based hydrothermal method and an investigation of the dependence of the morphology evolution of the self-assembled flower-like...
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báo cáo hóa học: " The effect of consequent exposure of stress and dermal application of low doses of chlorpyrifos on the expression of glial fibrillary acidic protein in the hippocampus of adult mice" pptx
Ngày tải lên :
20/06/2014, 00:20
... expression of glial fibrillary acidic protein in the cerebellum of the offspring in late puberty Arch Toxicol 2004, 78 (8):4 67- 476 19 Singh A, Naidu PS, Gupta S, Kulkarni SK: Effect of Natural and Synthetic ... The effect of consequent exposure of stress and dermal application of low doses of chlorpyrifos on the expression of glial fibrillary acidic protein in the hippocampus of adult mice Journal of ... expression [ 17, 18] The effect of dermal application of CPF on GFAP expression in the hippocampus has not been reported The aim of this study was to determine the expression of GFAP in the hippocampal...
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Báo cáo hóa học: " A rapid, convenient, solventless green approach for the synthesis of oximes using grindstone chemistry" docx
Ngày tải lên :
20/06/2014, 22:20
... Commun 41:1 071 –1 076 doi:10.1080/003 979 1100 379 778 3 31 Damljanovic I, Vukicevic M, Vukicevic RD (2006) A simple synthesis of oximes Monatsh Chem 1 37: 301–305 doi:10.10 07/ s0 070 6-005-04 27- 3 32 Irwing-Sax ... to the synthesis of aliphatics, alicyclics, aromatics, amino acids and peptides, terpenes and steroids of pharmaceutical interest Mini Rev Org Chem 6:241– 274 doi:10.2 174 / 1 570 1930 978 9 371 5 87 28 ... for the required period of time On completion of the reaction as Table Reusability of Bi2O3 in the preparation of 2b using 60 mol% of the catalyst Entry Run number Time Yield (%) 1 96 2 87 3...
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Báo cáo hóa học: " An alternative route for the synthesis of silicon nanowires via porous anodic alumina masks" potx
Ngày tải lên :
21/06/2014, 01:20
... distribution The inset of (b) shows the Au nanoparticle The inset of (c) corresponds to the EDX analysis of the Si NWs shows the histogram plot for the diameter distribution of the synthesized Si ... the pores of the AAO mask and will be responsible for the constant dimensions of the synthesized nanowires Figure shows the surface of the AAO-Si substrate, once the Figure Diagram of the CVD system ... growth The Si used in the growth process of nanowires is obtained from thermally generated defects on the surface of Si (100) These defects can be observed subsequently to the synthesis of Si...
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Báo cáo hóa học: " Effect of ion implantation energy for the synthesis of Ge nanocrystals in SiN films with HfO2/SiO2 stack tunnel dielectrics for memory application" pot
Ngày tải lên :
21/06/2014, 05:20
... ignored because of the absence of discrete charge Sahu et al Nanoscale Research Letters 2011, 6: 177 http://www.nanoscalereslett.com/content/6/1/ 177 Page of Figure C-V characteristics of Ge+-implanted ... nonvolatile memories Appl Phys Lett 20 07, 90:223504 doi:10.1186/1556- 276 X-6- 177 Cite this article as: Sahu et al.: Effect of ion implantation energy for the synthesis of Ge nanocrystals in SiN films ... A3 The SiN layer underwent a swelling of about nm, whereas the thickness of the underlying HfO and SiO layers remain almost the same as in the as-deposited sample In contrast, HREM image of sample...
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Báo cáo hóa học: " A Temperature Window for the Synthesis of Single-Walled Carbon Nanotubes by Catalytic Chemical Vapor Deposition of CH4 over Mo2-Fe10/MgO Catalyst" pptx
Ngày tải lên :
22/06/2014, 00:20
... 4: 574 – 577 575 Fig Sketch map of the fluidized bed reactor The growth of SWCNTs was carried out in a fluidizedbed which is shown in Fig In a typical experiment, about 100 mg catalyst was put into the ... study the influence of growth temperature on the purity of prepared tube samples, we give the curve (Fig 4) showing the dependence of ID/IG on the growth temperature From Fig 4, two kinds of ID/IG ... doi:10.1038/41 972 577 A Thess, R Lee, P Nikolaev et al., Science 273 , 483 (1996) doi: 10.1126/science. 273 .5 274 .483 L Qingwen, Y Hao, C Yan et al., J Mater Chem 12, 1 179 (2002) doi:10.1039/b10 976 3f 10...
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