keyword
MENU ▼
Read by QxMD icon Read
search

NMR

keyword
https://www.readbyqxmd.com/read/29050261/alpha-linolenic-acid-stabilizes-hif-1-%C3%AE-and-downregulates-fasn-to-promote-mitochondrial-apoptosis-for-mammary-gland-chemoprevention
#1
Subhadeep Roy, Atul Kumar Rawat, Shreesh Raj Sammi, Uma Devi, Manjari Singh, Swetlana Gautam, Rajnish Kumar Yadav, Jitendra Kumar Rawat, Lakhveer Singh, Mohd Nazam Ansari, Abdulaziz S Saeedan, Rakesh Pandey, Dinesh Kumar, Gaurav Kaithwas
Alpha linolenic acid is an essential polyunsaturated fatty acid and is reported to have the anti-cancer potential with no defined hypothesis or mechanism/s. Henceforth present study was in-quested to validate the effect of alpha linolenic acid on mitochondrial apoptosis, hypoxic microenvironment and de novo fatty acid synthesis using in-vitro and in-vivo studies. The IC50 value of alpha linolenic acid was recorded to be 17.55μM against ER+MCF-7 cells. Treatment with alpha linolenic acid was evident for the presence of early and late apoptotic signals along with mitochondrial depolarization, when studied through acridine orange/ethidium bromide and JC-1 staining...
September 19, 2017: Oncotarget
https://www.readbyqxmd.com/read/29049889/early-metabolic-response-after-resistance-exercise-with-blood-flow-restriction-in-well-trained-men-a-metabolomics-approach
#2
Denis F Valério, Ricardo Berton, Miguel S Conceição, Rafael R Canevarolo, Mara Patrícia T Chacon-Mikahil, Cláudia R Cavaglieri, Gabriela V Meirelles, Ana C Zeri, Cleiton A Libardi
The present study aimed to compare the early metabolic response between high-load resistance exercise (HL-RE) and low-load resistance exercise with blood flow restriction (LL-BFR). Nine young well-trained men participated in a randomized crossover design in which each subject completed LL-BFR, HL-RE or condition control (no exercise) with a one-week interval between them. Blood samples were taken immediately before and five minutes after the exercise sessions. Nuclear magnetic resonance (NMR) spectroscopy identified and quantified 48 metabolites, six of which presented significant changes among the exercise protocols...
October 19, 2017: Applied Physiology, Nutrition, and Metabolism, Physiologie Appliquée, Nutrition et Métabolisme
https://www.readbyqxmd.com/read/29049867/ion-pair-and-solvation-dynamics-of-bmim-bf4-water-system
#3
João Cascão, Wagner Silva, Ana S D Ferreira, Eurico J Cabrita
In this work, [Bmim][BF4 ]/water mixtures were analysed over the whole water composition (xw ) in order to study the rotational and translational behaviour of the ions. We employed a multinuclear NMR approach to determine anion/cation/water diffusion coefficients and longitudinal relaxation rates at different water content. In neat IL the cation diffuses faster than the anion and at low xw anions and cations share almost the same diffusion coefficient, but above a critical water concentration the anion begins to diffuse faster than the cation...
October 19, 2017: Magnetic Resonance in Chemistry: MRC
https://www.readbyqxmd.com/read/29048910/solvent-dielectricity-modulated-helical-assembly-and-morphologic-transformation-of-achiral-surfactant-inorganic-cluster-ionic-complexes
#4
Jing Zhang, Xiaofei Chen, Wen Li, Bao Li, Lixin Wu
Ionic complexes comprising of single/double chain cationic surfactant and Lindqvist-type polyoxomolybdate anionic cluster were used for controlled self-assembly in organic solutions. In the solvent with low dielectric constant the complexes self-assembled into flat ribbon like lamellar aggregations with an inverse bilayer substructure where the cluster located at the middle. Under the condition of increased dielectric constant, the solvent triggered the formation of helical self-assemblies, which finally transformed from helical ribbons to the flower-like assemblies due to the bilayer becoming excessive twisting...
October 19, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/29048892/antiplasmodial-chromanes-and-chromenes-from-the-monotypic-plant-species-koeberlinia-spinosa
#5
Christopher Charles Presley, Ana Lisa Valenciano, Maria L Fernández-Murga, Yongle Du, Narasimhamurthy Shanaiah, Maria B Cassera, Michael Goetz, Jason A Clement, David G I Kingston
Nine new compounds containing either a chromane or chromene ring moiety were isolated from the monotypic plant Koeberlinia spinosa. Compounds 1-4 are chromanes with all possible E and Z isomers of the isoprenoid side chain, with compound 5 a methylated derivative of 1. Compounds 6 and 7 were assigned as diastereomeric cyclized derivatives of 2 and were probably artifacts formed during the extraction or the isolation processes. Compounds 8 and 9 were characterized as new chromenes. Structure elucidation of 1-9 was conducted via 1D and 2D NMR spectroscopic data interpretation, and absolute configurations were determined by ECD spectroscopic analysis...
October 19, 2017: Journal of Natural Products
https://www.readbyqxmd.com/read/29048831/-fabrication-of-acylsemicarbazide-based-porous-organic-polymer-for-selective-enrichment-of-glycopeptides
#6
Hongwei Wang, Zhongshan Liu, Xiaojun Peng, Junjie Ou, Mingliang Ye
An acylsemicarbazide-based porous organic polymer (POP) was facilely prepared by the polymerization of benzene-1,3,5-tricarbohydrazide (BTZ) and 1,4-phenylene diisocyanate (PDI). The physical properties of as-synthesized material were characterized by Fourier-transform infrared spectroscopy (FT-IR), solid-state cross polarisation magic angle spinning carbon-13 nuclear magnetic resonance (CP-MAS (13)C NMR), nitrogen adsorption/desorption measurement, water contact angle and so on. The specific surface area was 166 m(2)/g, and the water contact angle was 46...
July 8, 2017: Se Pu, Chinese Journal of Chromatography
https://www.readbyqxmd.com/read/29048793/-separation-and-purification-of-the-components-in-trachelospermum-jasminoides-by-two-dimensional-hydrophilic-interaction-liquid-chromatography-reversed-phase-liquid-chromatography
#7
Youmei Jia, Jianfeng Cai, Huaxia Xin, Jiatao Feng, Yanhui Fu, Qing Fu, Yu Jin
A preparative two dimensional hydrophilic interaction liquid chromatography/reversed-phase liquid chromatography (Pre-2D-HILIC/RPLC) method was established to separate and purify the components in Trachelospermum jasminoides. The pigments and strongly polar components were removed from the crude extract after the active carbon decolorization and solid phase extraction processes. A Click XIon column (250 mm×20 mm, 10 μm) was selected as stationary phase and water-acetonitrile as mobile phases in the first dimensional HILIC...
June 8, 2017: Se Pu, Chinese Journal of Chromatography
https://www.readbyqxmd.com/read/29048734/imidazolium-based-ionic-liquids-as-efficient-reagents-for-lignin-c-o-bond-cleavage
#8
Marina Thierry, Amel Majira, Bruce Pégot, Laurent Cézard, Flavien Bourdreux, Gilles Clément, François Perreau, Stéphanie Boutet-Mercey, Patrick Diter, Giang Vo-Thanh, Catherine Lapierre, Paul-Henri Ducrot, Emmanuel Magnier, Stephanie Baumberger, Betty Cottyn
Lignin chemical demethylation in ionic liquids was investigated using pure lignin-model monomers and dimer together with dioxan isolated lignins from poplar, miscanthus and maize. Different methylimidazolium ionic liquids (ILs) were compared, according to two different heating processes, microwave irradiation and conventional heating in sealed tube. The conversion yield and influence of the treatments on lignin structure were assessed by 31P NMR, size exclusion chromatography and thioacidolysis. The acidic IL [HMIM][Br] was shown to be an effective combination solvent/reagent for the demethylation and even depolymerisation of lignin...
October 19, 2017: ChemSusChem
https://www.readbyqxmd.com/read/29048717/unexpected-crystallization-patterns-of-zinc-boron-imidazolate-framework-zbif-1-nmr-crystallography-of-integrated-metal-organic-frameworks
#9
Libor Kobera, Jan Rohlicek, Jiri Czernek, Sabina Abbrent, Magda Streckova, Tibor Sopcak, Jiri Brus
Framework materials, both metal-organic frameworks (MOFs) and inorganic frameworks (zeolites), are porous systems with regular structures that provide valuable properties suitable for sorption, catalysis, molecular sieving, etc. Herein, we present an efficient, experimental/computational strategy allowing for the detailed characterization of a polycrystalline MOF system, ZBIF-1, with two integrated unit cells on the atomic-resolution level. Although high-resolution 1H, 11B, 13C and 15N MAS NMR spectra provided valuable structural information on the co-existence of two distinct asymmetric units in the investigated system, the utilized NMR crystallography approach combining XRPD, ssNMR and DFT calculations allowed us to firmly define the exact structure of the secondary crystalline phase and, furthermore, to resolve the mutual interconnectivity of the two crystalline frameworks...
October 19, 2017: Chemphyschem: a European Journal of Chemical Physics and Physical Chemistry
https://www.readbyqxmd.com/read/29048398/glucopyranosylidene-spiro-thiazolinones-synthetic-studies-and-determination-of-absolute-configuration-by-tddft-ecd-calculations
#10
Katalin E Szabó, Sándor Kun, Attila Mándi, Tibor Kurtán, László Somsák
Reactions of O-peracylated C-(1-bromo-β-d-glucopyranosyl)formamides with thioamides furnished the corresponding glucopyranosylidene-spiro-thiazolin-4-one. While O-debenzoylations under a variety of conditions resulted in decomposition, during O-deacetylations the addition of MeOH to the thiazolinone moiety was observed, and with EtOH and water similar adducts were isolated or detected. The structure and stereochemistry of the new compounds were established by means of NMR and electronic circular dichroism (ECD) data supported by time-dependent density functional theory ECD (TDDFT-ECD) calculations...
October 19, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29048391/downhole-applications-of-magnetic-sensors
#11
REVIEW
Chinthaka P Gooneratne, Bodong Li, Timothy E Moellendick
In this paper we present a review of the application of two types of magnetic sensors-fluxgate magnetometers and nuclear magnetic resonance (NMR) sensors-in the oil/gas industry. These magnetic sensors play a critical role in drilling wells safely, accurately and efficiently into a target reservoir zone by providing directional data of the well and acquiring information about the surrounding geological formations. Research into magnetic sensors for oil/gas drilling has not been explored by researchers to the same extent as other applications, such as biomedical, magnetic storage and automotive/aerospace applications...
October 19, 2017: Sensors
https://www.readbyqxmd.com/read/29048381/self-assembly-with-2-6-bis-1-pyridin-4-ylmethyl-1h-1-2-3-triazol-4-yl-pyridine-silver-i-and-iron-ii-complexes
#12
Daniel A W Ross, Dan Preston, James D Crowley
A new "click" ligand, 2,6-bis(1-(pyridin-4-ylmethyl)-1H-1,2,3-triazol-4-yl)pyridine (L) featuring a tridentate 2,6-bis(1,2,3-triazol-4-yl)pyridine (tripy) pocket and two pyridyl (py) units was synthesized in modest yield (42%) using the copper(I) catalyzed azide-alkyne cycloaddition (CuAAC) reaction. The coordination chemistry of the ligand with silver(I) and iron(II) ions was examined using a battery of solution (¹H and DOSY (diffusion ordered spectroscopy) nuclear magnetic resonance (NMR), infrared and absorption spectroscopies, high-resolution electrospray ionization mass spectrometry (HR-ESI-MS)), and solid state (X-ray crystallography, elemental analysis) techniques...
October 19, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29048351/bacterial-substrate-transformation-tracked-by-stable-isotope-guided-nmr-metabolomics-application-in-a-natural-aquatic-microbial-community
#13
Mario Uchimiya, Yuuri Tsuboi, Kengo Ito, Yasuhiro Date, Jun Kikuchi
The transformation of organic substrates by heterotrophic bacteria in aquatic environments constitutes one of the key processes in global material cycles. The development of procedures that would enable us to track the wide range of organic compounds transformed by aquatic bacteria would greatly improve our understanding of material cycles. In this study, we examined the applicability of nuclear magnetic resonance spectroscopy coupled with stable-isotope labeling to the investigation of metabolite transformation in a natural aquatic bacterial community...
October 19, 2017: Metabolites
https://www.readbyqxmd.com/read/29048157/paramagnetic-19-f-relaxation-enhancement-in-nickel-ii-complexes-of-n-trifluoroethyl-cyclam-derivatives-and-cell-labeling-for-19-f-mri
#14
Jan Blahut, Karel Bernášek, Andrea Gálisová, Vít Herynek, Ivana Císařová, Jan Kotek, Jan Lang, Stanislava Matějková, Petr Hermann
1,8-Bis(2,2,2-trifluoroethyl)cyclam (te2f) derivatives with two coordinating pendant arms involving methylenecarboxylic acid (H2te2f2a), methylenephosphonic acid (H4te2f2p), (2-pyridyl)methyl (te2f2py), and 2-aminoethyl arms (te2f2ae) in 4,11-positions were prepared, and their nickel(II) complexes were investigated as possible (19)F MR tracers. The solid-state structures of several synthetic intermediates, ligands, and all complexes were confirmed by X-ray diffraction analysis. The average Ni···F distances were determined to be about 5...
October 19, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/29048154/hexanuclear-and-trinuclear-metal-complexes-of-a-giant-octadecaaza-macrocycle
#15
Janusz Gregoliński, Katarzyna Ślepokura, Jerzy Lisowski
A large macrocyclic ligand containing six pyridine fragments and six diaminocyclopentane fragments is able to form hexanuclear Zn(II) and Ni(II) complexes as well as a trinuclear Zn(II) complex. X-ray crystal structures of these complexes indicate quite different ligand conformations. In the hexanuclear Zn(II) derivative with chloride counteranions metal ions have a distorted-trigonal-bipyramidal geometry and occupy loop sections formed by the highly folded macrocycle, which adopts a globular shape. In the hexanuclear Ni(II) derivative with nitrate counteranions metal ions exhibit a distorted-octahedral geometry and the ligand conformation is much more open, while in the trinuclear Zn(II) complex the macrocycle wraps around the octahedral metal ions...
October 19, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/29048088/synthesis-characterization-and-biological-activity-of-new-cyclometallated-platinum-iv-iodido-complexes
#16
Emma Bauer, Xavier Domingo, Cristina Balcells, Ibrahim H Polat, Margarita Crespo, Josefina Quirante, Josefa Badía, Laura Baldomà, Mercè Font-Bardia, Marta Cascante
The synthesis of six novel cyclometallated platinum(iv) iodido complexes is accomplished by intermolecular oxidative addition of methyl iodide (compounds 2a-2c) or iodine (compounds 3a-3c) upon cyclometallated platinum(ii) compounds [PtX{(CH3)2N(CH2)3NCH(4-ClC6H3)}] (1a-1c: X = Cl, CH3 or I). The X-ray molecular structures of platinum(ii) compound 1c and platinum(iv) compounds 3b and 3a' (an isomer of 3a) are reported. The cytotoxic activity against a panel of human adenocarcinoma cell lines (A-549 lung, MDA-MB-231 and MCF-7 breast, and HCT-116 colon), DNA interaction, topoisomerase I, IIα, and cathepsin B inhibition, and cell cycle arrest, apoptosis and ROS generation of the investigated complexes are presented...
October 19, 2017: Dalton Transactions: An International Journal of Inorganic Chemistry
https://www.readbyqxmd.com/read/29048081/influence-of-size-shape-heteroatom-content-and-dispersive-contributions-on-guest-binding-in-a-coordination-cage
#17
Susanne Löffler, Axel Wuttke, Bo Zhang, Julian J Holstein, Ricardo A Mata, Guido H Clever
A halide-triggered metallosupramolecular host was systematically studied for the uptake of small neutral molecules using NMR and MS experiments. Starting from benzene, cyclic guests were screened with respect to size (ring count), shape (flatness, 3D structure, substitution pattern, flexibility) and hetero atom content (number, position, donor character). 5-Rings and substituted 5/6-rings bind only weakly, while oversized (e.g. naphthalene, adamantane, ferrocene) and linear alkanes do not bind at all. Bridged 6-rings of the norbornane type and in particular DABCO bind strongly, likewise other guests with oppositely arranged hetero atoms...
October 19, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/29047314/phytochemical-investigation-and-acetylcholinesterase-inhibitory-activity-of-bark-of-hymenodictyon-orixense
#18
Nattawut Suchaichit, Somdej Kanokmedhakul, Kwanjai Kanokmedhakul, Panawan Moosophon, Chantana Boonyarat, Kusawadee Plekratoke, Ruchanok Tearavarich, Natcha P Suchaichit
The chemical investigation of the methanol extract of Hymenodictyon orixense bark, a Thai medicinal herb, provided five compounds. Their structures were identified on the basis of 1D NMR and MS data, as well as by comparison of the data with published values, as an iridoid glycoside: loganin (1), four coumarins: scopoletin (2), scopolin (3), hymexelsin (4) and scopoletin 7-O-β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside (5). Compounds 1-5 showed acetylcholinesterase (AChE) inhibitory activity in the range of 13...
October 19, 2017: Natural Product Research
https://www.readbyqxmd.com/read/29047313/two-new-hirsutane-type-sesquiterpenoids-chondrosterins-n-and-o-from-the-marine-fungus-chondrostereum-sp
#19
Lei Huang, Wen-Jian Lan, Hou-Jin Li
The marine fungus Chondrostereum sp. was collected from a soft coral Sarcophyton tortuosum from the South China Sea. This fungus was cultured in glucose-peptone-yeast (GPY) medium and the culture broth was extracted with EtOAc. By the method of (1)H NMR pre-screening and tracing the diagnostic proton signals of the methyl groups, two new hirsutane-type sesquiterpenoids, chondrosterins N and O (1 and 2) were isolated from the metabolite extracts. Their structures were elucidated on the basis of MS, 1D and 2D NMR data...
October 19, 2017: Natural Product Research
https://www.readbyqxmd.com/read/29047311/catomentosaponin-a-new-triterpene-saponin-from-the-roots-of-catunaregam-tomentosa
#20
Sutin Kaennakam, Kitiya Rassamee, Pongpun Siripong, Santi Tip-Pyang
A new triterpene saponin, catomentosaponin (1) and 11 known analogues (2-12) were isolated from the roots of Catunaregam tomentosa. The structures of 1-12 were determined on the basis of extensive NMR and MS data analysis. The sugar residues were identified by co-TLC and HPLC analysis after hydrolysis. All isolated compounds were evaluated for their cytotoxicity against KB and HeLa cell lines. Compound 2 showed moderate cytotoxicity against KB cell with IC50 value of 24.84 μM.
October 19, 2017: Natural Product Research
keyword
keyword
5983
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"