keyword
MENU ▼
Read by QxMD icon Read
search

Pots

keyword
https://www.readbyqxmd.com/read/29334462/pot-economy-autooxidative-condensation-of-2-aryl-2-lithio-1-3-dithianes
#1
João R Vale, Tatu Rimpiläinen, Elina Sievanen, Kari Rissanen, Carlos A M Afonso, Nuno R Candeias
The autooxidative condensation of 2-aryl-2-lithio-1,3-dithianes is here reported. Treatment of 2-aryl-1,3-dithianes with n-BuLi in the absence of any electrophile leads to condensation of three molecules of 1,3-dithianes and formation of highly functionalized α-thioether ketones orthothioesters in 51-89% yields upon air exposure. The method was further expanded to benzaldehyde dithioacetals, affording corresponding orthothioesters and α-thioether ketones in 48-97% yields. The experimental results combined with density functional theory studies support a mechanism triggered by the autooxidation of 2-aryl-2-lithio-1,3-dithianes to yield a highly reactive thioester that undergoes condensation with two other molecules of 2-aryl-2-lithio-1,3-dithiane...
January 15, 2018: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/29334104/one-pot-cascade-synthesis-of-azabicycles-via-the-nitro-mannich-reaction-and-n-alkylation
#2
Wannaporn Disadee, Somsak Ruchirawat
A one-pot, metal-free process for the synthesis of azabicycles is developed. The key transformations involved a cascade of double intramolecular cyclizations via the nitro-Mannich reaction and N-alkylation, providing various ring systems of azabicycles in yields up to 81% and an isomeric ratio of 62 : 1. This approach offers considerable advantages in terms of the handling of small molecules, the flexibility to introduce a functionalized side chain, and gives direct access to various azabicycles.
January 15, 2018: Organic & Biomolecular Chemistry
https://www.readbyqxmd.com/read/29334102/ru-nanoparticles-dispersed-on-magnetic-yolk-shell-nanoarchitectures-with-fe3o4-core-and-sulfoacid-containing-periodic-mesoporous-organosilica-shell-as-bifunctional-catalysts-for-direct-conversion-of-cellulose-to-isosorbide
#3
Ying Yang, Wen Zhang, Feng Yang, Biao Zhou, Dehong Zeng, Na Zhang, Guoming Zhao, Shijie Hao, Xin Zhang
A green and sustainable approach for biorefining involves the development of bifunctional catalysts for the one-pot conversion of cellulosic biomass to isosorbide. This requires highly efficient, easily separated and versatile metal-acid catalysts for hydrolysis-hydrogenation-dehydration cascade reactions. Herein, we report a new type of metal-acid bifunctional catalyst by dispersing Ru nanoparticles (NPs) on magnetic yolk-shell nanoarchitectures comprising an Fe3O4 core and a sulfoacid (SO3H)-containing periodic mesoporous organosilica shell...
January 15, 2018: Nanoscale
https://www.readbyqxmd.com/read/29334086/n-doped-graphene-supported-pdcu-nanoalloy-as-efficient-catalyst-for-reducing-cr-vi-by-formic-acid
#4
Shuangzhi Li, Lijun Liu, Qing Zhao, Chiyang He, Weikai Liu
Reducing Cr(vi) to Cr(iii) with formic acid is desirable for environmental protection, but the sluggish kinetics limits its practical application, which currently motivates the intensive study of efficient catalysts for this redox reaction. Here bimetallic PdCu nanoalloy (∼5 nm in size) supported by N-doped graphene was synthesized through a one-pot hydrothermal process. The catalytic activity of PdCu nanoalloy highly depends on the Pd/Cu atomic ratio and N-doped graphene support. The obtained Pd6Cu4/NG shows superior catalysis towards the Cr(vi) reduction by formic acid with a high kinetic constant (kn = 23...
January 15, 2018: Physical Chemistry Chemical Physics: PCCP
https://www.readbyqxmd.com/read/29333848/highly-stable-and-luminescent-perovskite-polymer-composites-from-a-convenient-and-universal-strategy
#5
Yumeng Xin, Hongjie Zhao, Jiuyang Zhang
Extensive attention has been received in recent years for perovskite-polymer composites due to their combination of properties from polymers and perovskites. In this work, a convenient and universal strategy is reported to prepare cesium lead bromide (CsPbBr3) or organolead halide CH3NH3PbBr3 polymer composites. This technique integrates the formation of perovskite crystals and polymer matrix in a one-pot reaction, avoiding the tedious separation and preparation of perovskites. The method is universal for most of commercially available monomers and polymers, which has been verified in this report by poly(methyl methacrylate) (PMMA), poly(butyl methacrylate) (PBMA) and polystyrene (PS)...
January 15, 2018: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/29333553/microwave-assisted-synthesis-of-tempo-labeled-hydrogels-traceable-with-mri
#6
Emanuele Mauri, Edoardo Micotti, Arianna Rossetti, Lucio Melone, Simonetta Papa, Giulia Azzolini, Stefano Rimondo, Pietro Veglianese, Carlo Punta, Filippo Rossi, Alessandro Sacchetti
Polymer functionalization strategies have recently attracted considerable attention for several applications in biomaterials science. In particular, technological advancements in medical imaging have focused on the design of polymeric matrices to improve non-invasive approaches and diagnostic accuracy. In this scenario, the use of microwave irradiation of aqueous solutions containing appropriate combinations of polymers is gaining increasing interest in the synthesis of sterile hydrogels without using monomers, eliminating the need to remove unreacted species...
January 15, 2018: Soft Matter
https://www.readbyqxmd.com/read/29332837/a-novel-electroanalytical-assay-for-sulfamethazine-determination-in-food-samples-based-on-conducting-polymer-nanocomposite-modified-electrodes
#7
Ya-Ling Su, Shu-Hua Cheng
The toxicity of sulfa drugs has attracted great attention, and the reported electrochemical methods for sulfa drugs usually employ a high oxidation potential. In this work, a one-pot synthesized conducting polymer nanocomposite containing poly(3,4-ethylenedioxythiophene) (PEDOT) and MnO2 was cast on a screen-printed carbon electrode (SPCE), and the modified electrode showed superior electrochemical activity over a bare electrode for sulfamethazine (SMZ) determination. The SMZ detection was based on the electrochemical oxidation product, which showed an adsorptive property and exhibited a redox couple at 0...
April 1, 2018: Talanta
https://www.readbyqxmd.com/read/29332798/supported-carbon-dots-serve-as-high-performance-adsorbent-for-the-retention-of-trace-cadmium
#8
Yi-Kun Li, Ting Yang, Ming-Li Chen, Jian-Hua Wang
Carbon dots were prepared via a one-pot hydrothermal route, and a new solid-phase extraction (SPE) adsorbent was developed by immobilizing the carbon dots on the microcarrier cytopore, shortly termed as C-dots@cytopore. The C-dots@cytopore composites were characterized by means of FT-IR, SEM, XPS and fluorescence spectrometry. The performance of the composites for the adsorption of heavy metals was thoroughly evaluated by using cadmium as a model. The binding of cadmium on C-dots@cytopore fits Langmuir adsorption, and the adsorption dynamic follows pseudo-second-order adsorption kinetics model...
April 1, 2018: Talanta
https://www.readbyqxmd.com/read/29332596/synthesis-and-characterization-of-thiocarbohydrazones-and-their-inhibitory-potential-against-ignored-disease-leishmaniasis
#9
Nida Ghouri, Khalid Mohammed Khan, Arshia, M Iqbal Choudhary, Shahnaz Perveen
BACKGROUND: Leishmaniasis is a protozoan parasitic vector-borne disease which is endemic in 88 tropical countries. Infected sand fly is the main cause of this disease while, there are several vectors, parasites, and reservoirs involved in the transmission of this disease. Leishmania donovani, L. infantum, and L. chagasi are. common disease causing species, spread through sandflies. It is considered to be a focal disease having scattered foci. Leishmaniasis is a disease with a broad clinical spectrum...
January 14, 2018: Medicinal Chemistry
https://www.readbyqxmd.com/read/29332147/phosphorus-allocation-and-phosphatase-activity-in-grasses-with-different-growth-rates
#10
Leandro Bittencourt de Oliveira, Anderson Cesar Ramos Marques, Fernando Luiz Ferreira de Quadros, Júlia Gomes Farias, Rogério Piccin, Gustavo Brunetto, Fernando Teixeira Nicoloso
Different growth rates of grasses from South American natural grasslands are adaptations to soils of low fertility. Grasses with fast growth rate are species with an accumulation of nutrients in soluble forms, with a high metabolic rate. This work aimed to study whether grasses with different growth rates have different phosphorus (P) uptake and efficiency of P use with high and low P availability in soil, as well as whether phosphatase activity is related to the species growth rate and variations in P biochemical forms in the tissues...
January 13, 2018: Oecologia
https://www.readbyqxmd.com/read/29331491/investigating-the-relationship-between-cardiac-interoception-and-autonomic-cardiac-control-using-a-predictive-coding-framework
#11
Andrew P Owens, Karl J Friston, David A Low, Christopher J Mathias, Hugo D Critchley
Predictive coding models, such as the 'free-energy principle' (FEP), have recently been discussed in relation to how interoceptive (afferent visceral feedback) signals update predictions about the state of the body, thereby driving autonomic mediation of homeostasis. This study appealed to 'interoceptive inference', under the FEP, to seek new insights into autonomic (dys)function and brain-body integration by examining the relationship between cardiac interoception and autonomic cardiac control in healthy controls and patients with forms of orthostatic intolerance (OI); to (i) seek empirical support for interoceptive inference and (ii) delineate if this relationship was sensitive to increased interoceptive prediction error in OI patients during head-up tilt (HUT)/symptom provocation...
January 9, 2018: Autonomic Neuroscience: Basic & Clinical
https://www.readbyqxmd.com/read/29330821/effects-of-ferrous-sulfate-amendment-and-water-management-on-rice-growth-and-metal-loid-accumulation-in-arsenic-and-lead-co-contaminated-soil
#12
Lina Zou, Shu Zhang, Dechao Duan, Xinqiang Liang, Jiyan Shi, Jianming Xu, Xianjin Tang
Arsenic (As) and lead (Pb) commonly co-exist with high concentrations in paddy soil mainly due to human activities in south of China. This study investigates the effect of ferrous sulfate (FeSO4) amendment and water management on rice growth and arsenic (As) and lead (Pb) accumulation in rice plants. A paddy soil co-contaminated with As and Pb was chosen for the pot experiment with three FeSO4 levels (0, 0.25, and 1%, on a dry weight basis) and two water managements (flooded, non-flooded). The concentrations of As and Pb in iron plaques and rice plants were determined...
January 12, 2018: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/29330767/ivabradine-for-the-treatment-of-postural-orthostatic-tachycardia-syndrome-a-systematic-review
#13
REVIEW
Megan E Gee, Alicia K Watkins, Jamie N Brown, Emily J A Young
INTRODUCTION: Postural orthostatic tachycardia syndrome (POTS) impacts millions of patients, but there is currently no gold standard treatment for this condition. Ivabradine is a novel heart rate (HR) lowering agent that acts on the sinoatrial node cells by selectively inhibiting the If-current. OBJECTIVE: The objective of this systematic review is to evaluate the evidence for the efficacy and safety of ivabradine for the treatment of POTS. METHODS: MEDLINE (from 1956 to August 2017) and EMBASE (from 1957 to August 2017) were queried with the following search term: "postural orthostatic tachycardia syndrome" OR "postural tachycardia syndrome" OR "chronic orthostatic intolerance" AND "ivabradine...
January 12, 2018: American Journal of Cardiovascular Drugs: Drugs, Devices, and Other Interventions
https://www.readbyqxmd.com/read/29329269/design-synthesis-and-safener-activity-of-novel-methyl-r-n-benzoyl-dichloroacetyl-thiazolidine-4-carboxylates
#14
Li-Xia Zhao, Hao Wu, Yue-Li Zou, Qing-Rui Wang, Ying Fu, Chun-Yan Li, Fei Ye
A series of novel methyl (R)-N-benzoyl/dichloroacetyl-thiazolidine-4-carboxylates were designed by active substructure combination. The title compounds were synthesized using a one-pot route from l-cysteine methyl ester hydrochloride, acyl chloride, and ketones. All compounds were characterized by IR, ¹H NMR, 13C NMR, and HRMS. The structure of 4q was determined by X-ray crystallography. The biological tests showed that the title compounds protected maize from chlorimuron-ethyl injury to some extent. The ALS activity assay showed that the title compounds increased the ALS activity of maize inhibited by chlorimuron-ethyl...
January 12, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29329008/selective-formation-of-copper-nanoparticles-from-acid-mine-drainage-using-nanoscale-zerovalent-iron-particles
#15
R A Crane, D J Sapsford
Nanoscale zerovalent iron (nZVI) has been investigated for the selective formation of Cu nanoparticles from acid mine drainage (AMD) taken from a legacy mine site in the UK. Batch experiments were conducted containing unbuffered (pH 2.67 at t = 0) and pH buffered (pH < 3.1) AMD which were exposed to nZVI at 0.1-2.0 g/L. Results demonstrate that nZVI is selective for Cu, Cd and Al removal (>99.9% removal of all metals within 1 h when nZVI ≥ 1.0 g/L) from unbuffered AMD despite the coexistent of numerous other metals in the AMD, namely: Na, Ca, Mg, K, Mn and Zn...
December 18, 2017: Journal of Hazardous Materials
https://www.readbyqxmd.com/read/29327924/two-step-macrocycle-synthesis-by-classical-ugi-reaction
#16
Eman M M Abdelraheem, Samad Khaksar, Katarzyna Kurpiewska, Justyna Kalinowska-Tłuścik, Shabnam Shaabani, Alexander Dömling
The direct non-peptidic macrocycle synthesis of α-isocyano-ω-amines via the classical Ugi 4-component reaction (U-4CR) is introduced. Herein, an efficient and flexible, just 2-step procedure to complex macrocycles is reported. In the first step, the reaction between unprotected diamines and isocyanocarboxylic acids gives high diversity of unprecedented building blocks in high yield. In the next step, the α-isocyano-ω-amines undergo an U-4CR with high diversity of aldehydes and carboxylic acids in a one-pot procedure...
January 12, 2018: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/29327591/post-ugi-cascade-transformations-for-accessing-diverse-chromenopyrrole-collections
#17
Vunnam Srinivasulu, Scott McN Sieburth, Raafat El-Awady, Noor M Kariem, Hamadeh Tarazi, Matthew John O'Connor, Taleb H Al-Tel
Employing a build/couple/pair strategy, a serendipitous one-pot protocol for the diastereoselective construction of diverse collections of chromenopyrroles is described. This methodology features an unprecedented five-step cascade including azomethine ylide generation followed by in situ intramolecular [3 + 2]-cycloaddition. Furthermore, this protocol was extended to access enantiopure chromenopyrroles using amino acids as chiral auxiliary. Moreover, postpairing reactions were employed to increase the diversity and complexity of our pilot compound collections...
January 12, 2018: Organic Letters
https://www.readbyqxmd.com/read/29327138/handling-and-reporting-of-transperineal-template-prostate-biopsy-in-europe-a-web-based-survey-by-the-european-network-of-uropathology-enup
#18
Solene-Florence Kammerer-Jacquet, Eva Compérat, Lars Egevad, Ondra Hes, Jon Oxley, Murali Varma, Glen Kristiansen, Daniel M Berney
Transperineal template prostate biopsies (TTPB) are performed for assessments after unexpected negative transrectal ultrasound biopsies (TRUSB), correlation with imaging findings and during active surveillance. The impact of TTPBs on pathology has not been analysed. The European Network of Uropathology (ENUP) distributed a survey on TTPB, including how specimens were received, processed and analysed. Two hundred forty-four replies were received from 22 countries with TTPBs seen by 68.4% of the responders (n = 167)...
January 11, 2018: Virchows Archiv: An International Journal of Pathology
https://www.readbyqxmd.com/read/29326991/a-facile-one-pot-synthesis-of-acrylated-hyaluronic-acid
#19
Sigen A, Qian Xu, Peter McMichael, Yongsheng Gao, Xiaolin Li, Xi Wang, Udo Greiser, Dezhong Zhou, Wenxin Wang
The synthesis of acrylated hyaluronic acid (HA-A) normally requires 2 to 3 steps of modification, needs laborious purification and also increases the risks of HA degradation. Here, we report that the conjugation of acrylate groups to hyaluronic acid can be successfully achieved via a new facile one-pot approach. Two types of new HA-A hydrogels (via chemical or UV crosslinking) were developed and applied for 3D cell encapsulation.
January 12, 2018: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/29326369/successful-treatment-of-postural-orthostatic-tachycardia-and-mast-cell-activation-syndromes-using-naltrexone-immunoglobulin-and-antibiotic-treatment
#20
Leonard B Weinstock, Jill B Brook, Trisha L Myers, Brent Goodman
A patient with severe postural orthostatic tachycardia syndrome (POTS) and mast cell activation syndrome (MCAS) received immunotherapy with low-dose naltrexone (LDN) and intravenous immunoglobulin (IVIg) and antibiotic therapy for small intestinal bacterial overgrowth (SIBO). A dramatic and sustained response was documented. The utility of IVIg in autoimmune neuromuscular diseases has been published, but clinical experience with POTS is relatively unknown and has not been reported in MCAS. As a short-acting mu-opioid antagonist, LDN paradoxically increases endorphins which then bind to regulatory T cells which regulate T-lymphocyte and B-lymphocyte production and this reduces cytokine and antibody production...
January 11, 2018: BMJ Case Reports
keyword
keyword
26362
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"