Search

Synthesis of various fine chemicals and pharmaceuticals are regulated through selective hydrogenation of α,β-unsaturated aldehydes. Hydrocinnamaldehyde is one of the important compounds in perfumery and flavouring industries. It is highly precarious and challenging to control the product selectivity as well as conversion in cinnamaldehyde hydrogenation. In this study, an effective hydrogenation of cinnamaldehyde was attained in presence of aqueous-protic organic medium by utilizing Pd/CMS and other additives of alkali such as K2CO3. The Pd/CMS catalyst along with alkali media catalyzed the hydrogenation of C=C selectively in cinnamaldehyde in order to form hydrocinnamaldehyde with 100% conversion rate. Additionally, the parallel hydrogenation of C=O and C=C bonds in cinnamaldehyde takes place in absence of media. The C=O bond reduction in cinnamaldehyde can be restricted through K2CO3 addition to aqueous-protic solution. The active sites of palladium were found to be uniform and analyzed using HRTEM data. Based on the mechanism involved in micropores of carbon molecular sieves, the key role of promoter is associated with hydrogenation of cinnamaldehyde. The catalytic criterion was appropriate with the acquired activity data.

This study focused on kinetic modelling of a specific type of multistep heterogeneous reaction comprising exothermic and endothermic reaction steps, as exemplified by the experimental kinetic curves for the thermal decomposition of (E)-4-Bromo-2-[(phenylimino)methyl]- phenol (4B2PMP) crystal. The crystal was grown by a slow evaporation method. The cell parameters and crystalline perfection of the grown crystal were studied by single and powder X-ray diffractions. Thermal stability and phase change of 4B2PMP crystal were analyzed by TG/DTA. The microhardness study has revealed the soft nature. UV-visible analysis reveals the wide range of optical window of the optical transmission from 199 nm to 1100 nm. The bandgap of the crystal is found to be 3.24 eV. The FESEM of the crystals was spherically shaped and consisted of a core-shell structure with internal aggregates. The antimicrobial activity of title crystal was tested against different microorganisms by disc diffusion method. The results reveal that the title compound have effective antimicrobial activities.

This paper reports the behavior of 13X zeolite supported Ce, Cu, Co, Ag and Mn metal oxides toward ozone catalytic oxidation (OZCO) of toluene and the influence of moisture on the decomposition process. The simple impregnation method was adapted to disperse the metal oxides and found highly active for toluene oxidation in the presence of ozone. The steady-state activities and ozone decomposition data reveal that the activity is in the order of Mn/13X > Ce/13X > Cu/13X > Ag/13X > Co/13X and Mn/13X > Cu/13X > Ce/13X > Ag/13X > Co/13X, respectively. The extent of ozone decomposition is responsible for the degree of oxidative decomposition of toluene over the Mn/13X catalyst. The addition of moisture (Relative Humidity of 25%) to the reaction mixture considerably enhanced the conversion of toluene and selectivity to carbon oxides from 49% to 61% and 38% to 53% respectively, on the Mn/13X catalyst. The two sets of experiment results reveal that the surface adsorbed by-products such as benzene, benzaldehyde, p-methyl phenol and oxalic acid are considerably oxidized to CO2 in the presence of moisture whereas in the absence of moisture these by-products are slowly oxidized. The activity data in the presence of ozone and moisture also reveal that the moisture has considerably enhanced the activation of surface adsorbed by-products than that of initial toluene oxidation. Based on the temperature programmed desorption and temperature programmed oxidation studies, the addition of moisture decreased the by-products accumulation thereby, reduced the catalyst deactivation and enhanced the extended oxidation of toluene on the Mn/13X zeolite. Keywords: 13X zeolite, Ozone, Catalytic oxidation, Toluene, Moisture

A series of 2-methyl-1-[(1-phenyl-1H-1,2,3-triazol-4-yl)methyl]-2-(4-{[(1-phenyl-1H-1,2,3-triazol-4-yl)methyl}amino]phenyl)-2,3-dihydroquinazolin-4(1H)-ones have been synthesized by click chemistry from 2-methyl-1-(prop-2-yn-1-yl)-2-[4-(prop-2-yn-1-ylamino)phenyl]-2,3-dihydroquinazolin-4(1H)-one and substituted azides. The newly synthesized quinazolinones have been characterized by 1H and 13C NMR, IR, and mass spectral data and elemental analyses.

The present work reports the application of ozone and effect of cobalt oxide content on the vapor phase selective oxidation of cyclohexane. The catalysts with various cobalt loadings (0.5–10.0 wt%) prepared by a wet impregnation method followed by microwave drying. The one wt% cobalt catalyst (Co-1) exhibited the better conversion (16.5%) as well as selectivity to cyclohexanone/cyclohexanol (K/A, 64%) among the other cobalt catalysts at 110 °C, which might be due to the formation of isolated or fine cobalt particles on the surface of the catalyst and the strong Lewis acidity. Further, high moisture content (above 40%) is significantly increased the K/A selectivity from 64 to 71% on the Co-1 catalyst. The absence of cobalt oxide particles in the high resolution-transmission electron microscopy (HR-TEM) at lower cobalt loadings (

Vapour phase catalytic degradation of diethyl sulfide (DES) (simulant of a potential chemical warfare agent: sulfur mustard) at higher concentration (∼1200 ppm) is carried out in a fixed bed flow reactor over Mn/zeolite-13X catalysts of different manganese contents. The reaction is studied in the temperature range of 60–180 °C using ozone as the oxidizing agent. The influence of various process parameters such as reaction temperature, metal content, gas hourly space velocities (GHSV), ozone-to-DES mole ratio and water vapor are studied for getting maximum activity of the catalysts. Results reveal that reaction temperature and water vapor has significant effect on the conversion of DES and stability of the catalyst. Higher ozone-to-DES mole ratio facilitates the complete mineralization of DES at mild reaction conditions. The major products identified in the gas phase degradation of DES are carbon oxides, ethylene, acetaldehyde, acetic acid, sulfur dioxide and diethyl sulfone. Traces of diethyl sulfoxide, ethanol, thioethanol, methane thiol, formic acid are also identified in GC-MS analyses. The plausible degradation pathway is proposed based on the products identified by analyses results. The Mn/zeolite-13X catalysts of different composition are prepared by wet impregnation method and characterized by different characterization techniques.

The nanostructured proton-containing δ-MnO2 (H-δ-MnO2) catalyst was prepared by proton exchange of K-containing δ-MnO2 (K-δ-MnO2) nanoflakes. Energy-dispersive spectroscopy analysis showed that the K+ cations effectively leached away and replaced with H+ ions. Exchange of K+ ions with H+ ions in K-δ-MnO2 catalyst facilitated high surface area, high reducibility and better diffusion of ozone into the channels of 2D structure. It also reduced the average oxidation state of Mn (3.90 to 3.59) and increased the surface oxygen vacancies (0.62 to 0.87) from K-δ-MnO2 to H-δ-MnO2 catalyst. These all parameters are efficiently increased the decomposition of ozone from K-δ-MnO2 to H-δ-MnO2 catalyst.

This paper reports the application of adsorption followed by ozone oxidation in the pressure swing adsorption (PSA) process for the removal of VOCs from contaminated air streams. For that 13X molecular sieves and o -xylene selected as adsorbent and contaminant (one of the VOCs), respectively. The adsorption capacity of 13X molecular sieves for o -xylene is significantly increased from 0.6 to 2.8 mmol/g with pressure from 0.5 to 5.0 kg/cm 2 and these values are relatively good compatible with the Freundlich isotherm model. The 13X molecular sieves are efficiently regenerated in 70 min by ozone oxidation process at 25 °C and the adsorbed o -xylene is significantly oxidized to the CO 2 . In four successive cycles of adsorption followed by ozone oxidation process, the adsorption efficiency of 13X molecular sieves is not affected (±5%). Further, the adsorption-ozone oxidation process embedded PSA system is operated continuously for 50 h and there is no breakthrough observed in the fresh air. So that, the combination of adsorption followed by ozone oxidation with PSA process seems to be the better technology for the removal of VOCs from the contaminated air streams.

The title compound, C13H10INO, is not planar as the dihedral angle between the planes of the two aryl rings is 44.5 (9)°. The configuration about the central C=N bond is E, and there is an intramolecular O—H...N hydrogen bond which generates an S(6) ring. The molecular packing is stabilized by weak C—H...π interactions. The structure was refined as a two-component inversion twin.

This article reports the application of ozone for the selective oxidation of cyclohexane over 13X molecular sieve supported various metal oxides at ambient temperatures. From the SEM, XRD and HR-TEM results, the impregnated metal oxides are highly dispersed on the support. The activity results reveal that Co/MS, Mo/MS, Cu/MS, and Ag/MS catalysts produce cyclohexanone/cyclohexanol as selective oxidation products, whereas Ce/MS, Mn/MS, and V/MS catalysts yield, predominantly, CO and CO2. Among them, Co/MS catalyst exhibits better conversion of 12.2% with selectively of 58% to cyclohexanone/cyclohexanol, which is attributed to the simultaneous activation of ozone and cyclohexane (-C-H bond) at ambient conditions.

A simple and efficient oxidative decontamination method was developed for sulfur mustard (HD), a potential chemical warfare agent. The method involves treatment of chemical warfare agent HD and its...

Zeolite-13X-supported Fe (Fe/zeolite-13X) catalysts with various Fe contents were prepared by the wet impregnation method. The catalysts were characterized by N2 adsorption-desorption isotherms to estimate the Brunauer–Emmett–Teller surface areas and Barrett–Joyner–Hanlenda pore size distributions. X-ray diffraction, scanning electron microscopy, temperature-programmed reduction, and temperature-programmed desorption of NH3 were used to investigate the textural properties of the Fe/zeolite-13X catalysts. Their catalytic activities were determined for the complete oxidation of 1,4-dioxane using air as the oxidant in a fixed‐bed flow reactor in the temperature range 100–400 °C. The influences of various process parameters, such as reaction temperature, metal loading, and gas hourly space velocity (GHSV), on the dioxane removal efficiency by catalytic oxidation were investigated. The stability of the catalyst was tested at 400 °C by performing time-on-stream analysis for 50 h. The Fe/zeolite-13X catalyst with 6 wt% Fe exhibited the best catalytic activity among the Fe/zeolite-13X catalysts at 400 °C and a GHSV of 24000 h−1, with 97% dioxane conversion and 95% selectivity for the formation of carbon oxides (CO and CO2). Trace amounts (< 3%) of acetaldehyde, ethylene glycol monoformate, ethylene glycol diformate, 1,4-dioxane-2-ol, 1,4-dioxane-2- one, and 2-methoxy-1,3-dioxalane were also formed as degradation products. A plausible degradation mechanism is proposed based on the products identified by GC-MS analysis.

The efficient citral hydrogenation was achieved in aqueous media using Pd/CMS and alkali additives like K2CO3. The alkali concentrations, reaction temperature and the Pd metal content were optimized to enhance the citral hydrogenation under aqueous media. In the absence of alkali, citral hydrogenation was low and addition of alkali promoted to ~92% hydrogenation without reduction in the selectivity to citronellal. The alkali addition appears to be altered the palladium sites. The pore size distribution reveals that the pore size of these catalysts is in the range of 0.96 to 0.7 nm. The palladium active sites are also quite uniform based on the TPR data. The catalytic parameters are correlated well with the activity data.

Mutations in Fetal Liver Tyrosine Kinase 3 (FLT3) genes are implicated in the constitutive activation and development of Acute Myeloid Leukaemia (AML). They are involved in signalling pathway of autonomous proliferation and block differentiation in leukaemia cells. FLT3 is considered as a promising target for the therapeutic intervention of AML. There are a few missense mutations associated with FLT3 that are found in AML patients. The D835N mutation is the most frequently observed and the aspartic acid in this position acts as a key residue for the receptor activation. The present study aims to understand the structural effect of D835N mutation in FLT3. We carried out the molecular dynamics (MD) simulation for a period of 120 ns at 300 K. Root-mean square deviation, root-mean square fluctuations, surface accessibility, radius of gyration, hydrogen bond, eigenvector projection analysis, trace of covariance matrix, and density analysis revealed the instability of mutant (D835N) protein. Our study provides new insights on the conformational changes in the mutant (D835N) structure of FLT3 protein. Our observations will be useful for researchers exploring AML and for the development of FLT3 inhibitors.

The title compound, C13H10FNO, is essentially planar (r.m.s. deviation = 0.022 Å) and the dihedral angle between the planes of the two aryl rings is 0.69 (15)°. An intramolecular O—H...N hydrogen bond generates anS(6) ring. The crystal structure features C—H...O hydrogen bonds.

The T118M mutation in PMP22 gene is associated with Charcot Marie Tooth, type 1A (CMT1A). CMT1A is a form of Charcot-Marie-Tooth disease, the most common inherited disorder of the peripheral nervous system. Mutations in CMT related disorder are seen to increase the stability of the protein resulting in the diseased state. We performed SNP analysis for all the nsSNPs of PMP22 protein and carried out molecular dynamics simulation for T118M mutation to compare the stability difference between the wild type protein structure and the mutant protein structure. The mutation T118M resulted in the overall increase in the stability of the mutant protein. The superimposed structure shows marked structural variation between the wild type and the mutant protein structures.

The leaves of Murraya koenigii (Family: Rutaceae) are rich source of protein, dietary fiber, iron, calcium, β-carotene and antioxidants. In the present study, dried M. koenigii leaves powder (DMKLP) was incorporated at different levels (5, 10 and 15 %) in cookies and their rheological, physical, sensory and nutritional properties were evaluated. The results revealed that addition of increasing amount of DMKLP from 0 to 15 % increased farinograph water absorption of wheat flour and decreased dough stability; increased amylograph pasting temperature and decreased peak viscosity of wheat flour; increased hardness, decreased cohesiveness and springiness of cookie dough. The contents of protein, dietary fiber, minerals, β-carotene, and radical scavenging activity (RSA) in cookies increased with incorporation of increasing levels of DMKLP. Sensory evaluation showed that cookies with acceptable quality and typical curry leaf flavor could be obtained by incorporating DMKLP up to 10 %. Thus, the nutritional quality of cookies could be enhanced by incorporating DMKLP in a dose dependent manner.

Discovery of mupirocin, an antibiotic that targets isoleucyl-tRNA synthetase, established aminoacyl-tRNA synthetase as an attractive target for the discovery of novel antibacterial agents. Despite a high degree of similarity between the bacterial and human aminoacyl-tRNA synthetases, the selectivity observed with mupirocin triggered the possibility of targeting other aminoacyl-tRNA synthetases as potential drug targets. These enzymes catalyse the condensation of a specific amino acid to its cognate tRNA in an energy-dependent reaction. Therefore, each organism is expected to encode at least twenty aminoacyl-tRNA synthetases, one for each amino acid. However, a bioinformatics search for genes encoding aminoacyl-tRNA synthetases from Mycobacterium smegmatis returned multiple genes for glutamyl (GluRS), cysteinyl (CysRS), prolyl (ProRS) and lysyl (LysRS) tRNA synthetases. The pathogenic mycobacteria, namely, Mycobacterium tuberculosis and Mycobacterium leprae, were also found to possess two genes each for CysRS and LysRS. A similar search indicated the presence of additional genes for LysRS in gram negative bacteria as well. Herein, we describe sequence and structural analysis of the additional aminoacyl-tRNA synthetase genes found in M. smegmatis. Characterization of conditional expression strains of Cysteinyl and Lysyl-tRNA synthetases generated in M. smegmatis revealed that the canonical aminoacyl-tRNA synthetase are essential, while the additional ones are not essential for the growth of M. smegmatis.

DNA nanomachines are synthetic assemblies that switch between defined molecular conformations upon stimulation by external triggers. Previously, the performance of DNA devices has been limited to in vitro applications. Here we report the construction of a DNA nanomachine called the I-switch, which is triggered by protons and functions as a pH sensor based on fluorescence resonance energy transfer (FRET) inside living cells. It is an efficient reporter of pH from pH 5.5 to 6.8, with a high dynamic range between pH 5.8 and 7. To demonstrate its ability to function inside living cells we use the I-switch to map spatial and temporal pH changes associated with endosome maturation. The performance of our DNA nanodevices inside living systems illustrates the potential of DNA scaffolds responsive to more complex triggers in sensing, diagnostics and targeted therapies in living systems.

A test procedure for pressure swing adsorption (PSA) was established and elucidated for the air purification using methyl salicylate (MeS) and 5% (v/v) dimethyl methyl phosphonate (DMMP) in MeS containing air stream as feed. The effect of feed flow rate was studied by varying the flow from 5 lpm to 20 lpm, for both the molecules at 25 oC and 4 kg/cm2. The results revealed that the flow rate had a significant influence on the breakthrough time. A method was developed for the determination of feed, purge, and dry air composition, by the solvent extraction method using the XAD-2 and the average concentrations reported. The 13X molecular sieves were characterised for its structural and textural properties such as BET- SA, XRD, and FT-IR. The temperature programmed desorption of DMMP and MeS on 13X clearly demonstrated that it was easily regenerated at ~320 °C after prolonged field operation of PSA. The PSA results obtained with PSA composed molecular sieves appeared to give promising technology for air purification and specifically to the chemical warfare agents simulants.

Targeted delivery of lysosome-associated membrane proteins is important for lysosome stability and function. Here we identify a pathway for transport of lysosome-associated membrane proteins directly from the trans-Golgi network to late endosomes, which exists in parallel to mannose 6-phosphate receptor and clathrin-dependent transport of lysosomal enzymes to early endosomes. By immunoelectron microscopy we localized endogenous LAMP-1 and -2 as well as LAMP-1-mGFP to non-coated, biosynthetic carriers at the trans-Golgi network and near late endosomes. These LAMP carriers were negative for mannose 6-phosphate receptor, adaptor-protein complex-1, secretory albumin and endocytic markers, but contained the homotypic fusion and protein sorting complex component hVps41 and the soluble N-ethylmaleimide-sensitive factor attachment protein receptors protein VAMP7. Knockdown of hVps41 or VAMP7 resulted in the accumulation of lysosome-associated membrane protein carriers, whereas knockdown of hVps39 or hVps18 did not, indicating that the effect of hVps41 is independent of CORVET/HOPS. Mannose 6-phosphate receptor carriers remained unaffected upon hVps41 or VAMP7 knockdown, implicating that hVps41 and VAMP7 are specifically involved in the fusion of trans-Golgi network-derived lysosome-associated membrane protein carriers with late endosomes.

In mammalian cells, endocytosis of the fluid phase and glycosylphosphatidylinositol-anchored proteins (GPI-APs) forms GEECs (GPI-AP enriched early endosomal compartments) via an Arf1- and Cdc42-mediated, dynamin independent mechanism. Here we use four different fluorescently labeled probes and several markers in combination with quantitative kinetic assays, RNA interference and high resolution imaging to delineate major endocytic routes in Drosophila cultured cells. We find that the hallmarks of the pinocytic GEEC pathway are conserved in Drosophila and identify garz, the fly ortholog of the GTP exchange factor GBF1, as a novel component of this pathway. Live confocal and TIRF imaging reveals that a fraction of GBF1 GFP dynamically associates with ABD RFP (a sensor for activated Arf1 present on nascent pinosomes). Correspondingly, a GTP exchange mutant of GBF1 has altered ABD RFP localization in the evanescent field and is impaired in fluid phase uptake. Furthermore, GBF1 activation is required for the GEEC pathway even in the presence of Brefeldin A, implying that, like Arf1, it has a role in endocytosis that is separable from its role in secretion.