16 research outputs found
ChemInform Abstract: An Efficient and Modified Biginelli-Type Synthesis of 3,4-Dihydro-1H-indeno[1,2-d]pyrimidine-2,5-dione Using Phosphorous Pentoxide.
Study of Wear & Corrosion Resistance of Cold Sprayed Components
There is a major loss of material and process is observed in engineering application due to corrosion and wear. As the operating conditions are varying enormously, the mechanical component undergoes wear and corrosion for achieving wear resistant coating. Previously hot metal spray technique is used, which is now a day replaced with cold spray. There are many advantages of it over hot spray such as avoid melting and solidification, negligible thermal induced stress on substrate, avoid undesirable phases, avoid oxidation and higher deposition efficiency, good surface finish etc. There is a brief enlightening on wear mechanisms observed (corrosion, fatigue, adhesive and abrasive wear). In this technique the deposition efficiency is more. It’s Deposition Efficiency increases as the velocity of powder is increased. It can coat 5 – 50 mm ultra thick coating to serve its purpose. The case study shows utilization of cold spray technique and different material which coats substrate and their results. This case study is of orthopedic implants and effect of cold spray coating of different metals and their positive effects on human body. It shows that Tantalum gives a better wear resistance, good bio compatibility as well as long life (50 years). As Ta is having high surface energy, there is a better interaction between cell and materia
An Efficient and Modified Biginelli-Type Synthesis of 3,4-Dihydro-1H-indeno[1,2-d]pyrimidine-2,5-dione Using Phosphorous Pentoxide
<div><p></p><p>A simple, clean and convenient one-pot method has been developed for the synthesis of 4-phenyl-3,4-dihydro-1H-indeno[1,2-d]pyrimidine-2,5-dione and 4-phenyl-2-thioxo-1,2,3,4-tetrahydro-5H-indeno[1,2-d]pyrimidine-5-one by multicomponent condensation of 1,3-indanedione, aromatic aldehydes and urea/thiourea using phosphorus pentoxide in ethanol under reflux conditions. The simple workup procedure and moderate to good yields within short time are some important features of this protocol. The synthesized compounds have been interpreted on the basis of their spectroscopic data.</p>
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"Endangered or an artifact of unsound taxonomy? Case of the critically endangered bush frog Philautus sanctisilvaticus Das and Chanda, 1997"
Mirza, Zeeshan A., Warekar, Priya, Mohapatra, Pratyush P., Raju, David, Patil, Pranad, Dutta, Sushil K., Pal, Saunak (2019): "Endangered or an artifact of unsound taxonomy? Case of the critically endangered bush frog Philautus sanctisilvaticus Das and Chanda, 1997". Zootaxa 4683 (4): 563-576, DOI: https://doi.org/10.11646/zootaxa.4683.4.
Ecofriendly synthesis and biological evaluation of 4-(4-nitro-phenyl)-2-phenyl-1,4-dihydro-benzo[4,5]imidazo[1,2-a]pyrimidine-3-carboxylic acid ethyl ester derivatives as an antitubercular agents
<p>An ecofriendly route has been investigated for the synthesis of 4-(4-nitro-phenyl)-2-phenyl-1,4-dihydro-benzo[4,5]imidazo[1,2-a]pyrimidine-3-carboxylic acid ethyl ester derivatives by one-pot, three-component condensation of ethyl benzoylacetate, aromatic aldehydes, and 2-amino benzimidazole using 260 mol% of citric acid as reaction mediator. Citric acid is an inexpensive, nontoxic, and green medium with smoothly activates the rate of reaction. The synthesized compounds were assessed for in vitro antimycobacterial activity against <i>Mycobacterium tuberculosis</i> H<sub>37</sub>RV strain using the microplate alamar blue assay (MABA). The results indicate that among all the synthesized compound series, P-4 and P-9 compounds illustrate effective activity with a minimum inhibitory concentration of 25 µg/ml.</p
Uncatalyzed four-component synthesis of pyrazolopyranopyrimidine derivatives and their antituberculosis activities
<p>Fused pyrazolopyranopyrimidines containing both biologically active pyranopyrazole and pyranopyrimidine compounds were synthesized using a one-pot, four-component reaction of ethyl aceto acetate, hydrazine hydrate, benzaldehydes, and thiobarbituric acid without catalyst in ethanol. All target compounds obtained in very good to excellent yields over short reaction times by adapting a simple workup procedure. All the synthesized compounds exhibited good to excellent antituberculosis activities. The results shown that 4-(1<i>H</i>-imidazol-2-yl)-3-methyl-7-thioxo-4,6,7,8-tetrahydropyrazolo[4’,3′:5,6]pyrano[2,3-<i>d</i>] pyrimidin-5(1<i>H</i>)-one (<b>5a</b>) is a good antitubercular agent, as good as the standard streptomycin drug, based on minimum inhibitory concentration (MIC).</p