An Efficient Multi-component Synthesis of 6-Amino-3-methyl-4-Aryl-2,4- dihydropyrano[2,3-c]Pyrazole-5-carbonitriles

Multi-component reactions are effective in building complex molecules in a single step in a minimum amount of time and with facile isolation procedures; they have high economy1–7 and thus have become a powerful synthetic strategy in recent years.8–10 The multicomponent protocols are even more attractive when carried out in aqueous medium. Water offers several benefits, including control over exothermicity, and the isolation of products can be carried out by single phase separation technique. Pyranopyrazoles are a biologically important class of heterocyclic compounds and in particular dihydropyrano[2,3-c]pyrazoles play an essential role in promoting biological activity and represent an interesting template in medicinal chemistry. Heterocyclic compounds bearing the 4-H pyran unit have received much attention in recent years as they constitute important precursors for promising drugs.11–13 Pyrano[2,3-c]pyrazoles exhibit analgesic,14 anti-cancer,15 anti-microbial and anti-inflammatory16 activity. Furthermore dihydropyrano[2,3-c]pyrazoles show molluscidal activity17,18 and are used in a screening kit for Chk 1 kinase inhibitor activity.19,20 They also find applications as pharmaceutical ingredients and bio-degradable agrochemicals.21–29 Junek and Aigner30 first reported the synthesis of pyrano[2,3-c]pyrazole derivatives from 3-methyl-1-phenylpyrazolin-5-one and tetracyanoethylene in the presence of triethylamine. Subsequently, a number of synthetic approaches such as the use of triethylamine,31 piperazine,32 piperidine,33 N-methylmorpholine in ethanol,34 microwave irradiation,35,36 solvent-free conditions,37–39 cyclodextrins (CDs),40 different bases in water,41 γ -alumina,42 and l-proline43 have been reported for the synthesis of 6-amino-4-alkyl/aryl-3-methyl- 2,4-dihydropyrano[2,3-c]pyrazole-5-carbonitriles. Recently, tetraethylammonium bromide (TEABr) has emerged as mild, water-tolerant, eco-friendly and inexpensive catalyst. To the best of our knowledge, quaternary ammonium salts, more specifically TEABr, have notbeen used as catalysts for the synthesis of pyrano[2,3-c]pyrazoles, and we decided to investigate the application of TEABr as a catalyst for the synthesis of a series of pyrazole-fused pyran derivatives via multi-component reactions

Diffusion path during internal displacement reactions in multi-component oxides: Reaction between Fe and (Co,Mg)TiO3 solid solution at 1273 K

The reaction between Fe foil and a disc of ilmenite solid solution (Co-0.48 Ni-0.52) TiO3 was studied at 1273 K. At the metal/oxide interface, the displacement reaction, Fe + (Co,Mg)TiO3 = Co + (Fe,Mg)TiO3 occurs, resulting in an ilmenite solid solution containing three divalent cations. Ferrous ions diffuse into the oxide solid solution and cause the precipitation of Co-Fe alloy as discrete particles inside the oxide matrix. The morphology of the product layer was characterized by SEM. Only two phases, alloy and ilmenite, were detected in the reaction zone. This suggests that the local flux condition imposed by ilmenite stoichiometry (Co + Fe + Mg):Ti = 1:1] was satisfied during the reactive diffusion: (J(Co) + J(Fe) + J(Mg)) = J(Ti). The composition of the alloy and the oxide was determined using EPMA as a function of distance in the direction of diffusion. Although Mg does not participate in the displacement reaction, its composition in the ilmenite phase was found to be position dependent inside the reaction zone. The up-hill diffusion of inert Mg is caused by the development of chemical potential gradients as a result of displacement reaction. The evolution of composition gradients inside the reaction zone and the diffusion path in a ternary composition diagram of the system CoTiO3-FeTiO3-MgTiO3 are discussed. (C) 2010 Elsevier B.V. All rights reserved.

Multi component coupling reactions of N-acetyl-2-azetine

N-Acetyl-2-azetine undergoes Lewis acid catalysed formal [4+2]-cycloaddition with imines derived from aromatic amines to initially give an approximately 1: 1 mixture of exo-endo-diastereoisomeric 1-(2a,3,4,8b-tetrahydro-2H-1,4-diaza-cyclobuta[a]naphthalen-1-yl)-ethanone cycloadducts which were detected by proton NMR spectroscopy. These products, which were too unstable to isolate, and characterise, reacted further with aromatic amines to give 2,3,4-trisubstituted tetrahydroquinolines in good to excellent yield, predominantly as a single diastereoisomer, with the minor diastereoisomer converting to the major diastereoisomer on silica. The cycloaddition was irreversible and a mechanism is presented for the formation of the major diastereoisomer from the mixture of diastereoisomeric intermediates. A range of conditions is described for converting the 2,3,4-trisubsitituted tetrahydroquinolines into 2,3-disubstituted quinolines.

Multi-component Olivine for Lithium-Ion Hybrid Capacitor

A lithium-ion hybrid capacitor comprising of a battery type multi-component olivine (LiMn1/3Co1/3Ni1/3PO4) cathode and a capacitive type carbon negative electrode is reported. Olivine phosphate synthesized with chelating agent's polyvinylpyrrolidone (PVP) or triethanolamine (TEA) showed uniform carbon coating through in-situ process exhibiting a surface area 5.1 m(2)/g with porosity 0.02 cm(3)/g. The surface area for commercial carbon electrode was observed to be 1450 m(2)/g with high porosity 0.76 cm(3)/g. Galvanostatic charge/discharge cycling tests were conducted in the coin cells, olivine vs. Li, offering a cell voltage of 4.75 V vs. Li with a maximum specific capacitance of 125 F/g. In the case of olivine vs. carbon in a lithium-ion hybrid device delivered a high discharge capacitance of 86 F/g at a specific current of 0.12 A/g with a cycling retention of 53 F/g (38% loss) after 250 cycles. The obtained performance of PVP synthesized olivine material is manifested to uniform carbon coating and the trapped organic products that provide pathways for facile electrochemical reactions than their TEA counterparts.

Propagation of ion-acoustic waves in a multi-component plasma

The authors derive the Korteweg-de Vries equation in a multicomponent plasma that includes any number of positive and negative ions. The solitary wave solutions are also found explicitly for the case of isothermal and non-isothermal electrons.

A pilot RCT of a multi-component nutrition intervention for nursing home residents with dementia

Background Malnutrition and unintentional weight loss are major clinical issues in people with dementia living in residential aged care facilities (RACFs) and are associated with serious adverse outcomes. However, evidence regarding effective interventions is limited and strategies to improve the nutritional status of this population are required. This presentation describes the implementation and results of a pilot randomised controlled trial of a multi-component intervention for improving the nutritional status of RACF residents with dementia. Method Fifteen residents with moderate-severe dementia living in a secure long-term RACF participated in a five week pilot study. Participants were randomly allocated to either an Intervention (n=8) or Control group (n=7). The intervention comprised four elements delivered in a separate dining room at lunch and dinner: the systematic reinforcement of residents’ eating behaviors using a specific communication protocol; family-style dining; high ambiance table presentation; and routine Dietary-Nutrition Champion supervision. Control group participants ate their meals according to the facility’s standard practice. Baseline and follow-up assessments of nutritional status, food consumption, and body mass index were obtained by qualified nutritionists. Additional assessments included measures of cognitive functioning, mealtime agitation, depression, wandering status and multiple measures of intervention fidelity. Results No participant was malnourished at study commencement and participants in both groups gained weight from follow-up to baseline which was not significantly different between groups (t=0.43; p=0.67). A high degree of treatment fidelity was evident throughout the intervention. Qualitative data from staff indicate the intervention was perceived to be beneficial for residents. Conclusions This multi-component nutritional intervention was well received and was feasible in the RACF setting. Participants’ sound nutritional status at baseline likely accounts for the lack of an intervention effect. Further research using this protocol in malnourished residents is recommended. For success, a collaborative approach between researchers and facility staff, particularly dietary staff, is essential.

Grids with multiple batch systems for performance enhancement of multi-component and parameter sweep parallel applications

In this work, we evaluate the benefits of using Grids with multiple batch systems to improve the performance of multi-component and parameter sweep parallel applications by reduction in queue waiting times. Using different job traces of different loads, job distributions and queue waiting times corresponding to three different queuing policies(FCFS, conservative and EASY backfilling), we conducted a large number of experiments using simulators of two important classes of applications. The first simulator models Community Climate System Model (CCSM), a prominent multi-component application and the second simulator models parameter sweep applications. We compare the performance of the applications when executed on multiple batch systems and on a single batch system for different system and application configurations. We show that there are a large number of configurations for which application execution using multiple batch systems can give improved performance over execution on a single system.

Representation of Thermodynamic Properties of Dilute Multi-Component Solutions--Options and Constraints

The different formalisms for the representation of thermodynamic data on dilute multicomponent solutions are critically reviewed. The thermodynamic consistency of the formalisms are examined and the interrelations between them are highlighted. The options are constraints in the use of the interaction parameter and Darken's quadratic formalisms for multicomponent solutions are discussed in the light of the available experimental data. Truncatred Maclaurin series expansion is thermodynamically inconsistent unless special relations between interaction parameters are invoked. However, the lack of strict mathematical consistency does not affect the practical use of the formalism. Expressions for excess partial properties can be integrated along defined composition paths without significant loss of accuracy. Although thermodynamically consistent, the applicability of Darken's quadratic formalism to strongly interacting systems remains to be established by experiment.

Process-kinetics in facing targets sputtering of multi-component oxide thin films

The kinetics of the processes in facing targets sputtering of multicomponent oxide films is presented. The novel configuration of the process exhibits an enhanced ionization efficiency. Discharge diagnostics performed using optical emission spectroscopy revealed strong dependence of plasma parameters on process conditions. Numerical simulation based on thermalization and diffusion of sputtered atoms has been performed to estimate the transport efficiency in off-axis mode. Composition, structure and epitaxial quality of YBa2Cu3O7-x films prepared was found to be strongly dependent on atomic flux ratios (of Cu/Y and Ba/Y) arriving at the substrate, resputtering effect and phase stability of YBa2Cu3O7-x These studies have been shown to be useful in understanding the complex processes that occur in sputtering of multicomponent films. (C) 1999 Elsevier Science S.A. All rights reserved.

Executing Long-running Multi-component Applications on Batch Grids

Computational grids are increasingly being used for executing large multi-component scientific applications. The most widely reported advantages of application execution on grids are the performance benefits, in terms of speeds, problem sizes or quality of solutions, due to increased number of processors. We explore the possibility of improved performance on grids without increasing the application’s processor space. For this, we consider grids with multiple batch systems. We explore the challenges involved in and the advantages of executing long-running multi-component applications on multiple batch sites with a popular multi-component climate simulation application, CCSM, as the motivation.We have performed extensive simulation studies to estimate the single and multi-site execution rates of the applications for different system characteristics.Our experiments show that in many cases, multiple batch executions can have better execution rates than a single site execution.

Water gas shift reaction over multi-component ceria catalysts

This study reports the activity of ionic substituted bimetallic Cu-Ni-modified ceria and Cu-Fe-modified ceria catalysts for low-temperature water gas shift (WGS) reaction. The catalysts were synthesized in nano-crystalline size by a sonochemical method and characterized by XRD, TEM, XPS, TPR and BET surface analyzer techniques. Due to the ionic substitution of these aliovalent base metals, lattice oxygen in CeO2 is activated and these catalysts show high activity for WGS at low temperature. An increase in the reducibility and oxygen storage capacity of bimetallic substituted CeO2, as evidenced by H-2-TPR experiments, is the primary reason for the higher activity towards WGS reaction. In the absence of feed CO2 and H-2, 100% conversion of CO with 100% H-2 selectivity was observed at 320 degrees C and 380 degrees C, for Cu-Ni-modified ceria and Cu-Fe-modified ceria catalysts. Notably, in the presence of feed H2O. a reverse WGS reaction does not occur over these ceria modified catalysts. A redox reaction mechanism, involving oxidation of CO adsorbed on the metal was developed to correlate the experimental data and determine kinetic parameters. (C) 2012 Elsevier B.V. All rights reserved.

Large improvements in application throughput of long-running multi-component applications using batch grids

Computational grids with multiple batch systems (batch grids) can be powerful infrastructures for executing long-running multi-component parallel applications. In this paper, we evaluate the potential improvements in throughput of long-running multi-component applications when the different components of the applications are executed on multiple batch systems of batch grids. We compare the multiple batch executions with executions of the components on a single batch system without increasing the number of processors used for executions. We perform our analysis with a foremost long-running multi-component application for climate modeling, the Community Climate System Model (CCSM). We have built a robust simulator that models the characteristics of both the multi-component application and the batch systems. By conducting large number of simulations with different workload characteristics and queuing policies of the systems, processor allocations to components of the application, distributions of the components to the batch systems and inter-cluster bandwidths, we show that multiple batch executions lead to 55% average increase in throughput over single batch executions for long-running CCSM. We also conducted real experiments with a practical middleware infrastructure and showed that multi-site executions lead to effective utilization of batch systems for executions of CCSM and give higher simulation throughput than single-site executions. Copyright (c) 2011 John Wiley & Sons, Ltd.

Multi-component, Self-assembled, Functional Soft Materials

Supramolecular chemistry is an emerging tool for devising materials that can perform specified functions. The self-assembly of facially amphiphilic bile acid molecules has been extensively utilized for the development of functional soft materials. Supramolecular hydrogels derived from the bile acid backbone act as useful templates for the intercalation of multiple components. Based on this, synthesis of gel-nanoparticle hybrid materials, photoluminescent coating materials, development of a new enzyme assay technique, etc. were achieved in the author's laboratory. The present account highlights some of these achievements.

High-Temperature Deformation Processing Map Approach for Obtaining the Desired Microstructure in a Multi-component (Ni-Ti-Cu-Fe) Alloy

An equiatomic NiTiCuFe multi-component alloy with simple body-centered cubic (bcc) and face-centered cubic solid-solution phases in the microstructure was processed by vacuum induction melting furnace under dynamic Ar atmosphere. High-temperature uniaxial compression experiments were conducted on it in the temperature range of 1073 K to 1303 K (800 degrees C to 1030 degrees C) and strain rate range of 10(-3) to 10(-1) s(-1). The data generated were analyzed with the aid of the dynamic materials model through which power dissipation efficiency and instability maps were generated so as to identify the governing deformation mechanisms that are operative in different temperature-strain rate regimes with the aid of complementary microstructural analysis of the deformed specimens. Results indicate that the stable domain for the high temperature deformation of the multi-component alloy occurs in the temperature range of 1173 K to 1303 K (900 degrees C to 1030 degrees C) and (epsilon) over dot range of 10(-3) to 10(-1.2) s(-1), and the deformation is unstable at T = 1073 K to 1153 K (800 degrees C to 880 degrees C) and (epsilon) over dot = 10(-3) to 10(-1.4) s(-1) as well as T = 1223 K to 1293 K (950 degrees C to 1020 degrees C) and (epsilon) over dot = 10(-1.4) to 10(-1) s(-1), with adiabatic shear banding, localized plastic flow, or cracking being the unstable mechanisms. A constitutive equation that describes the flow stress of NiTiCuFe multi-component alloy as a function of strain rate and deformation temperature was also determined. (C) The Minerals, Metals & Materials Society and ASM International 2015

Biological application of multi-component nanowires in hybrid devices powered by F-1-ATPase motors

In this paper, construction of hybrid device by integrating nanowires with F1-ATPase motors is described. The nickel nanowires and multi-segment nanowires, including gold and nickel, were fabricated by electrochemical deposition in nanoporous templates. The nickel nanowires functionalized by biotinylated peptide can be assembled directly onto F1-ATPase motors to act as the propellers. If the multicomponent nanowires, including gold and nickel, were selectively functionalized by the thiol group modified ssDNA and the synthetic peptide, respectively, the biotinylated F1- ATPase motors can be attached to the biotinylated peptide on nickel segment of the nanowires. Then, the multi-component nanowires can also be used as the propellers, and one may observe the rotations of the multi-component nanowires driven by F1-ATPase motors. Therefore, introduction of multiple segments along the length of a nanowire can lead to a variety of multiple chemical functionalities, which can be selectively bound to cells and special biomolecules. This method provides an insight for the construction of other hybrid devices with its controlling arrangement of different biomolecule on designed nanometer scale structures.