the three major approaches to the synthesis of aromatic heterocycles

... majority of pharmaceuticals and biologically active agrochemicals are heterocycles The importance of heterocycles provides a new basis for the development of new methods for their synthesis Due to the ... the pharmaceutical industry as they make up a core part of several drugs The importance of heterocycles provides a significant basis for the development of new methods for their synthesis Further, ... regardless of the volume of the vessel Thus, in conventional heating methods for organic synthesis the heat is basically transferred by conductance and the extent of transfer of energy to the system...

Ngày tải lên: 29/05/2014, 17:31

... In the absence of a clinical evaluation, a simulator was developed to simulate 70 days of data and test the ability of the system to store large amounts of data and to manipulate these data to ... including the requirement to identify the monitored subject from others in the home (Biometrics signature), IR conflicts and the inability to monitor the subject outside of the home environment Monitoring ... required to remember to don the wearable unit for their mobility to be measured (Table 5) Though, it gives the possibility to the person to doff the wearable for a while and still be monitored by the...

Ngày tải lên: 05/03/2014, 21:20

... However, all these reported methods either produced solid nanorods, nanowires or hollow nanotubes but without pores on the wall To the best of our knowledge, very few reports on the synthesis of porous ... 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 ... 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...

Ngày tải lên: 19/03/2014, 16:48

... 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 ... amount of a TEMPO trap was added and the sonication took place under identical conditions to those of the synthesis of the metal oxides It is assumed that if hydroxyl radicals are formed they will ... to the methyl group, whereas the weak singlet peak at 3.3 ppm refers to the OH group The integration ratios of the benzene ring, the methyl group and the OH peak are 1:0.4:0.2, respectively The...

Ngày tải lên: 20/03/2014, 13:11

... provide DOF force/torque feedback, by adding encoders and motors at the tooltip of the device These extensions increase the perceived mass of the device and not offer the same performance of specific ... qualities of the Pantograph with an experiment; the acceleration measured at the tooltip of the device has a frequency spectrum close to the desired force signal In the end, the re-engineered Pantograph ... on the observation that the area of contact of the finger with an object changes during the exploration process The actuators in the device move a flat plate against the finger of the user to...

Ngày tải lên: 17/02/2016, 14:42

... parameters of the mycobacterial dehydrogenase determined for: (A) the L-gulono-1,4-lactone substrate in the presence of 121 lM cytochrome c; and (B) the cytochrome c substrate in the presence of 50 ... characterized up to now, and the first example of a specific, vitamin C biosynthetic enzyme of bacterial origin Further studies will be necessary to elucidate the role of the Rv1771 l-gulono-1,4-lactone dehydrogenase ... in agreement with the enzyme behavior in the presence of a detergent In contrast to the related aldonolactone oxidases [13,16,19], but similar to the plant l-galactono-1,4-lactone dehydrogenases...

Ngày tải lên: 07/03/2014, 12:20

... GDP-4-keto-6-deoxy-D-mannose reductase and the stereoselectivity of the reduction determines the direction of synthesis of these two 6-deoxyhexoses However, neither the gene encoding the biosynthesis of GDP-6-deoxy-D-talose ... content 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 ... h to hydrolyse them; they were then dried to remove the water and HCl The pellets were converted into the corresponding D-(+)-2-octylglycoside acetate by the method of Leontein et al [30] The...

Ngày tải lên: 17/03/2014, 10:20

... 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 ... 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 was found to be ... 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...

Ngày tải lên: 20/03/2014, 13:08

... 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 ... level of incorporation into DNA, but the level of labelled dTTP was very low [18] In organisms where NDK is present, the rate-limiting step in the synthesis of dNTPs ⁄ NTPs is not the conversion of ... (d)CMP Discussion The aim of the present study was to define the role of Ureaplasma NMPKs in the synthesis of nucleoside triphosphates Four Ureaplasma NMPKs were cloned, expressed and the recombinant...

Ngày tải lên: 30/03/2014, 08:20

... anodization, instead of a magnetic stirrer, ultrasonic waves were irradiated onto the solution to enhance the mobility of the ions inside the solution The anodization current was monitored continuously ... activity in the former This better activity is due either to the higher percentage of anatase (GXRD; Fig 9) in the material, which aids absorption of the illuminated light, or to better heteroatom doping ... view of (c) showing the compact nanotubes and the barrier layer The above experiments show that using ultrasonic waves for anodization can reduce the synthesis time by up to 50% and increase the...

Ngày tải lên: 05/05/2014, 15:26

... 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 metal atoms It was These intriguing ... emulsions for detoxification of pesticides suitable process for synthesis of nanoparticles [1] Certain disadvantages exist with the use is using of Co-Precipitation method [28, 29] of these adsorbents ... catalyst, toxic-waste 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...

Ngày tải lên: 06/05/2014, 08:55

... can entrap electrons from the semiconductor, the holes can diffuse to the surface of the semiconductor and cause oxidation of the organic dye Therefore, a high density of surface oxygen defects ... Metash Instruments Co Ltd., China) to monitor the degradation of the KGL The characteristic absorption peak of KGL at Ȝ=608 nm was chosen to monitor the photocatalytic degradation process For ... influence the photoactivity of the sample to some extent Comparison of the surface areas listed in Table shows that the ZnO sample synthesized at 120 ºC indeed had the largest surface area The XRD...

Ngày tải lên: 06/05/2014, 13:26

... characterization of carbonyl compounds [1,2].Conversions into nitriles [3], nitro compounds [4,5], nitrones [6], amines [7], and synthesis of azaheterocycles [8] are some of the synthetic applications of oximes ... out from the solution The precipitate was filtered out and dried in high vacuum to furnish the pure oxime in 60-98% yield 90 Page of run might be due to the loss of active sites of the catalyst ... mins 96 monitored by TLC, ethyl acetate (2 × 10 mL) was added to the reaction mixture and filtered to separate the Bi2O3 The filtrate was concentrated down to approx mL, then added water to it when...

Ngày tải lên: 20/06/2014, 22:20

... 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 melting of Si into the alloy [33] The diameter of the nanowires ranged from ca 30-50 nm, with an average size of ca 40 nm and was related to the pore size of the AAO mask HRTEM revealed the ... seen there, the metal deposition is homogeneously distributed due to the constant rotation of the sample holder that prevents the concentration of metal atoms in specific areas of the sample Thermal...

Ngày tải lên: 21/06/2014, 01:20

... properties of Si N [17], well-defined Ge-NCs are expected to be formed in the top nitride layer without any significant diffusion of Ge toward Si/tunnel oxide interface and/or to the surface of control ... In the images, the surface of SiN layer is indicated by a white line accumulation layer of the substrate), resulting in a shift of the C-V curve toward negative voltages [21,22] In general, the ... injected from the inversion layer of the Si substrate into the gate dielectric matrix When a negative voltage is applied, electrons are ejected back into the Si substrate (equivalent to hole injection...

Ngày tải lên: 21/06/2014, 05:20

... of Lys258 then acts as a catalyst for the 1,3-prototropic shift to form the ketimine The ketimine is hydrolyzed to yield the keto acid and PMP The following second half reaction consists of the ... 2002) The reaction starts with the deamination of aspartate to α-ketoglutarate In the resting enzyme PLP is covalently bound to the ε-amino group of a lysine (Lys258) in the active site of the ... catalyze the transfer of an amino group from a donor substrate to an acceptor, thus enabling the synthesis of a wide variety of chiral amines and amino acids Transaminases can be applied either for the...

Ngày tải lên: 21/06/2014, 17:20

... raised to the setting value in Ar atmosphere at a flow rate of 200 mL/min before CH4 was introduced into the reactor at 60 mL/min for 30 min, then CH4 was turned off and the furnace was cooled to ... increases to 950 °C, SWCNTs are hardly observed In order to 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 ... accords with the result of the TEM image (Fig 3a) The intensity ratio, ID/IG, is observed to decrease with increasing temperature (at 800 °C, the ID/IG is 0.47) Raman spectrum of the sample grown...

Ngày tải lên: 22/06/2014, 00:20

... for 12 h (Fig 1b) The diameters of the nanoparticles are in the range of 50–70 nm with an average diameter of 60 nm Using higher reaction time of 24 h, the average diameter of the nanoparticles ... composed of Ni and O, and the analysis in the NiO nanoparticles/nanoflowers indicates an atomic ratio of 86% Ni and 14% O, which is very near to the theoretical value (7% error is attributed to the ... only size, the geometry, and chemical homogeneity, but also the simplicity and practicability of synthesis techniques When developing a synthesis method for generation of nanostructures, the most...

Ngày tải lên: 22/06/2014, 01:20

... into the quartz tube for h at 500°C, in order to remove the presence of any oxygen on the surface of the alloy hydride catalysts Hydrogen flow was stopped and then furnace was heated up to the ... spectra of the alloy-filled MWNTs (Fig 2a) showed the presence of Zr, Cr, Fe and Ni; the constituents of the alloy, with a composition comparable to that of the initial alloy used for the preparation ... Dependence of carbon yield on the reaction temperature be through the precipitation of carbon in the form of MWNTs from the molten catalytic particles The melting temperatures of the alloy-C...

Ngày tải lên: 22/06/2014, 22:20

... can go into pores (really, only accessible to pores according to the molecular size of helium) The helium density gives a measure of the density of the carbon structure The total volume of pores ... washed to extract the excess of ZnCl2 The amount of ZnCl2 incorporated in the precursor and the temperature of heat treatment are the two variables with a direct incidence in the development of the ... following equation, (1) where W0 is the weight of the original carbon and W1 refers to the mass of the activated carbon The use of CO2 during the activation process of a carbon material develops narrow...

Ngày tải lên: 28/06/2014, 17:20