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https://www.readbyqxmd.com/read/28340474/studying-the-effects-of-natural-extracts-with-metabolomics-a-longitudinal-study-on-the-supplementation-of-healthy-rats-with-polygonum-cuspidatum-sieb-et-zucc
#1
Gregorio Peron, Jalal Uddin, Matteo Stocchero, Stefano Mammi, Elisabetta Schievano, Stefano Dall'Acqua
BACKGROUND: A longitudinal study was performed to evaluate the effects of Polygonum cuspidatum extract (standardized at 20% resveratrol) supplementation on healthy rats. The effects were explored by monitoring urinary metabolome changes using UPLC-HRMS and (1)H NMR-based approaches. The aim of the study was to explore the effects of P. cuspidatum supplementation on a healthy animal model using metabolomics, in order to determine possible modes of action and obtain information on bioactivity...
March 16, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28340472/characterization-of-an-unknown-impurity-in-doxofylline-using-lc-ms-and-nmr
#2
Peixi Zhu, Jingxian Lu, Liya Hong, Weike Su, Ann Van Schepdael, Erwin Adams
During quality control of doxofylline, a novel impurity was detected, which was above the identification threshold defined by ICH. First, a liquid chromatographic method compatible with mass spectrometric (MS) detection was developed. Based on tandem multistage MS and high resolution MS data, the unknown impurity was found to consist of two theophylline groups connected by a methylene group. The structure was further confirmed by 1D and 2D nuclear magnetic resonance (NMR) experiments after semi-preparative isolation...
March 18, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28340411/synthesis-and-biological-evaluation-of-novel-chalcone-derivatives-as-a-new-class-of-microtubule-destabilizing-agents
#3
Xiaochao Huang, Rizhen Huang, Lingxue Li, Shaohua Gou, Hengshan Wang
A series of novel chalcone derivatives were designed and synthesized as potential antitumor agents. Structures of target molecules were confirmed by (1)H NMR, (13)C NMR and HR-MS, and evaluated for their in vitro anti-proliferative activities using MTT assay. Among them, compound 12k displayed potent activity against the test tumor cell lines including multidrug resistant human cancer lines, with the IC50 values ranged from 3.75 to 8.42 μM. In addition, compound 12k was found to induce apoptosis in NCI-H460 cells via the mitochondrial pathway, including an increase of the ROS level, loss of mitochondrial membrane potential, release of cytochrome c, down-regulation of Bcl-2, up-regulation of Bax, activation of caspase-9 and caspase-3, respectively...
March 18, 2017: European Journal of Medicinal Chemistry
https://www.readbyqxmd.com/read/28340396/spectral-studies-on-anthracene-based-dual-sensor-for-hg-2-and-al-3-ions-with-two-distinct-output-modes-of-detection
#4
Navneet Kaur, Baljeet Kaur
A simple and easily synthesized colorimetric and fluorescent chemosensor 1, based on aromatic OH and imine moieties as a binding and anthracene as signaling unit, has been synthesized in a one-step procedure. The chemosensor 1 is developed as a dual chemosensor for detection of Hg(2+) and Al(3+) ions in CH3OH, which exhibited a color change from light yellow to dark yellow with Hg(2+) ions, enabling 1 a suitable "bare eye" indicator for Hg(2+) ions. On the other hand, fluorescent enhancement with blue shift along with brilliant cyan fluorescence was observed upon binding with Al(3+) ions...
March 15, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28340368/synthesis-molecular-docking-antimycobacterial-and-antimicrobial-evaluation-of-new-pyrrolo-3-2-c-pyridine-mannich-bases
#5
Gilish Jose, Tholappanavara H Suresha Kumara, Haliwana B V Sowmya, Dharmarajan Sriram, Tayur N Guru Row, Amar A Hosamani, Sunil S More, Bhavya Janardhan, B G Harish, Sandeep Telkar, Yalegara Siddappa Ravikumar
In this report, we describe the synthesis and biological evaluation of a new series of pyrrolo[3,2-c]pyridine Mannich bases (7a-v). The Mannich bases were obtained in good yields by one-pot three component condensation of pyrrolo[3,2-c]pyridine scaffold (6a-c) with secondary amines and excess of formaldehyde solution in AcOH. The chemical structures of the compounds were characterized by (1)H NMR, (13)C NMR, LC/MS and elemental analysis. Single crystal X-ray diffraction has been recorded for compound 7k ([C23H29ClN4](+2), H2O)...
March 16, 2017: European Journal of Medicinal Chemistry
https://www.readbyqxmd.com/read/28340309/analytical-techniques-in-lipidomics-state-of-the-art
#6
Kamil Jurowski, Kamila Kochan, Justyna Walczak, Małgorzata Barańska, Wojciech Piekoszewski, Bogusław Buszewski
Current studies related to lipid identification and determination, or lipidomics in biological samples, are one of the most important issues in modern bioanalytical chemistry. There are many articles dedicated to specific analytical strategies used in lipidomics in various kinds of biological samples. However, in such literature, there is lack of articles dedicated to a comprehensive review of the actual analytical methodologies used in lipidomics. The aim of this article is to characterize the lipidomics methods used in modern bioanalysis according to the methodological point of view: 1) chromatography/separation methods, 2) spectroscopic methods and 3) mass spectrometry and also hyphenated methods...
March 24, 2017: Critical Reviews in Analytical Chemistry
https://www.readbyqxmd.com/read/28340300/synthesis-of-3-o-sulfated-oligosaccharides-to-understand-the-relationship-between-structures-and-functions-of-heparan-sulfate
#7
Zhangjie Wang, Po-Hung Hsieh, Yongmei Xu, David Thieker, Evangeline Juan En Chai, Shaoshuai Xie, Brian Cooley, Robert Woods, Lianli Chi, Jian Liu
The sulfation at the 3-OH position of glucosamine is an important modification in forming structural domains for heparan sulfate to enable its biological functions. Seven 3-O-sulfotransferase isoforms in the human genome are involved in the biosynthesis of 3-O-sulfated heparan sulfate. As a rare modification present in heparan sulfate, the availability of 3-O-sulfated oligosaccharides is very limited. Here, we report the use of a chemoenzymatic synthetic approach to synthesize six 3-O-sulfated oligosaccharides, including three hexasaccharides and three octasaccharides...
March 24, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28339201/high-throughput-in-silico-structure-validation-and-revision-of-halogenated-natural-products-is-enabled-by-parametric-corrections-to-dft-computed-13-c-nmr-chemical-shifts-and-spin-spin-coupling-constants
#8
Andrei G Kutateladze, D Sai Reddy
Halogenated natural products constitute diverse and promising feedstock for molecular pharmaceuticals. However, their solution-structure elucidation by NMR presents several challenges, including the lack of fast methods to compute (13)C chemical shifts for carbons bearing heavy atoms. We show that parametric corrections to DFT-computed chemical shifts in conjunction with rff-computed spin-spin coupling constants allow for fast and reliable screening of a large number of reported halogenated natural products, resulting in expedient structure validation or revision...
March 24, 2017: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/28339195/the-electronic-configuration-and-ligand-nature-of-five-coordinate-iron-porphyrin-carbene-complexes-an-experimental-study
#9
Yulong Liu, Wei Xu, Jing Zhang, William Fuller, Charles E Schulz, Jianfeng Li
The five coordinate iron porphyrin carbene complexes [Fe(TPP)(CCl<u>2</u>)] (TPP = tetraphenylporphyrin), [Fe(TTP)(CCl<u>2</u>)] (TTP = tetratolylporphyrin) and [Fe(TFPP)(CPh<u>2</u>)] (TFPP = tetra(pentafluorophenyl)porphin), utilizing two types of carbene ligands (CCl<u>2</u> and CPh<u>2</u>), have been investigated by single crystal X-ray, XANES (X-ray Absorption Near Edge Spectroscopy), Mössbauer, NMR and UV-vis spectros-copies. The XANES unambiguously suggested the iron(II) oxida-tion state of the complexes...
March 24, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28339189/polymerization-induced-self-assembly-pisa-control-over-the-morphology-of-19f-containing-polymeric-nano-objects-for-cell-uptake-and-tracking
#10
Wei Zhao, Hang Thu Ta, Cheng Zhang, Andrew Keith Whittaker
Fluorine-containing polymeric materials are receiving increasing attention as imaging probes in fluorine-19 magnetic resonance imaging (19F MRI), for example to enable quantitative in vivo detection of cells. Here we describe the one-pot polymerization synthesis of 19F-containing functional poly(OEGA-co-TFEA)-b-poly(St-co-VBA) copolymers as a new class of fluorinated MRI agent. A range of nanoparticle morphologies, including spheres, worm-like particles and vesicles were formed as a consequence of polymerization-induced self-assembly (PISA)...
March 24, 2017: Biomacromolecules
https://www.readbyqxmd.com/read/28339126/boron-doped-polygonal-carbon-nano-onions-synthesis-and-applications-in-electrochemical-energy-storage
#11
Marta Eliza Plonska-Brzezinska, Olena Mykhailiv, Krzysztof Brzezinski, Bogdan Sulikowski, Zbigniew Olejniczak, Malgorzata Gras, Grzegorz Lota, Agustin Molina-Ontoria, Michal Jakubczyk, Luis Echegoyen
Doping of carbon nanostructures with heteroatoms, such as boron or nitrogen, is one of the most effective ways to change their properties to make them suitable for various applications. Carbon nano-onions (CNOs) doped with boron (B-CNOs) have been prepared by annealing (1650°C) nanodiamond particles (NDs) under an inert He atmosphere in the presence of B. Their physicochemical properties were measured using transmission (TEM) and scanning (SEM) electron microscopy, X-ray photoelectron spectroscopy (XPS), 10B and 11B solid-state MAS NMR spectroscopy, X-ray powder diffractions (XRD), Raman spectroscopy, porosimetry, and differential-thermogravimetric analyses (TGA-DTG)...
March 24, 2017: Chemistry: a European Journal
https://www.readbyqxmd.com/read/28338702/hydrogen-bonds-between-methanol-and-the-light-liquid-olefins-1-pentene-and-1-hexene-from-application-to-fundamental-science
#12
Zhaoxi Zhang, Tiancun Xiao, Hamid Al-Megren, Saud A Aldrees, Mohammad Al-Kinany, Vladimir L Kuznetsov, Maxim L Kuznetsov, Peter P Edwards
We have recently developed a new extraction process for significantly reducing the olefin content in commercial FCC gasoline. To gain insights into the origins of this process, we have investigated the dissolution of the light liquid olefins 1-pentene and 1-hexene in methanol through computer modelling together with NMR spectroscopy. We find two important hydrogen bonding modes for methanol olefin interactions - namely, O-Hπ and C-HO.
March 24, 2017: Chemical Communications: Chem Comm
https://www.readbyqxmd.com/read/28338625/-r-aloesaponol-iii-8-methyl-ether-from-eremurus-persicus-a-novel-compound-against-leishmaniosis
#13
Daniela Rossi, Karzan Mahmood Ahmed, Raffaella Gaggeri, Serena Della Volpe, Lauretta Maggi, Giuseppe Mazzeo, Giovanna Longhi, Sergio Abbate, Federica Corana, Emanuela Martino, Marisa Machado, Raquel Varandas, Maria do Céu Sousa, Simona Collina
Leishmaniosis is a neglected tropical disease which affects several millions of people worldwide. The current drug therapies are expensive and often lack efficacy, mainly due to the development of parasite resistance. Hence, there is an urgent need for new drugs effective against Leishmania infections. As a part of our ongoing study on the phytochemical characterization and biological investigation of plants used in the traditional medicine of western and central Asia, in the present study, we focused on Eremurus persicus root extract in order to evaluate its potential in the treatment of leishmaniosis...
March 24, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28338623/a-study-of-intramolecular-hydrogen-bonding-in-levoglucosan-derivatives
#14
Lucas Quiquempoix, Elena Bogdan, Neil J Wells, Jean-Yves Le Questel, Jérôme Graton, Bruno Linclau
Organofluorine is a weak hydrogen-bond (HB) acceptor. Bernet et al. have demonstrated its capability to perturb OH···O intramolecular hydrogen bonds (IMHBs), using conformationally rigid carbohydrate scaffolds including levoglucosan derivatives. These investigations are supplemented here by experimental and theoretical studies involving six new levoglucosan derivatives, and complement the findings of Bernet et al. However, it is shown that conformational analysis is instrumental in interpreting the experimental data, due to the occurrence of non-intramolecular hydrogen-bonded populations which, although minor, cannot be neglected and appears surprisingly significant...
March 24, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28338415/hyaluronic-acid-hydrogel-functionalized-with-self-assembled-micelles-of-amphiphilic-pegylated-kartogenin-for-the-treatment-of-osteoarthritis
#15
Mi-Lan Kang, Se-Young Jeong, Gun-Il Im
Synthetic hyaluronic acid (HA) containing a covalently integrated drug is capable of releasing therapeutic molecules and is an attractive candidate for the intra-articular treatment of osteoarthritis (OA). Herein, self-assembled PEGylated kartogenin (PEG/KGN) micelles consisting of hydrophilic polyethylene glycol (PEG) and hydrophobic KGN, which has been shown to induce chondrogenesis in human mesenchymal stem cells, were prepared by covalent crosslinking. HA hydrogels containing PEG/KGN micelles (HA/PEG/KGN) were prepared by covalently bonding PEG chains to HA...
March 24, 2017: Tissue Engineering. Part A
https://www.readbyqxmd.com/read/28338344/new-flavonol-glycoside-from-scabiosa-prolifera-l-aerial-parts-with-in-vitro-antioxidant-and-cytotoxic-activities
#16
Mahmoud A Al-Qudah, Noor K Otoom, Hala I Al-Jaber, Ayman M Saleh, Musa H Abu Zarga, Fatma U Afifi, Sultan T Abu Orabi
Phytochemical investigation of the chemical constituents of the aerial parts of Scabiosa prolifera L. led to the isolation of one new flavonol glycoside, kaempferol-3-O-(4″,6″-di-E-p-coumaroyl)-β-D-galactopyranoside (1), along with ten other known compounds including luteolin-7-O-(2″-O-ethyl-β-glucopyranoside), β-sitosterol, β-sitosterylglucoside, ursolic acid, corosolic acid, ursolic acid 3-O-β-D-arabinopyranoside, apigenin, methyl-α-D-glucopyranoside, luteolin-7-O-β-glucopyranoside and isoorientin...
March 24, 2017: Natural Product Research
https://www.readbyqxmd.com/read/28338341/natural-product-inhibitors-of-carbonic-anhydrase-i-and-ii-isoenzymes-osajin-and-pomiferin
#17
Esra Dilek, Hüseyin Serkan Erol, Ahmet Cakir, Murat Koc, Mesut Bünyami Halici
The aim of this study is to purify carbonic anhydrase I and II isoenzymes from human erythrocyte, isolate two natural products osajin (OSJ) and pomiferin (PMF) from Maclura pomifera fruits, and evaluate the in vitro effect of these natural metabolites on these isoenzymes. These natural products may be used as starting points for drug discovery (like drugs used in several therapeutic applications, including antiglaucoma activity). For the purification procedure, the Sepharose-4B-l-tyrosine-sulphonamide affinity chromatography was used...
March 24, 2017: Archives of Physiology and Biochemistry
https://www.readbyqxmd.com/read/28338318/iron-ii-complexes-with-scorpiand-like-macrocyclic-polyamines-kinetico-mechanistic-aspects-of-complex-formation-and-oxidative-dehydrogenation-of-coordinated-amines
#18
M Paz Clares, Laura Acosta-Rueda, Carmen E Castillo, Salvador Blasco, Hermas R Jiménez, Enrique García-España, Manuel G Basallote
The Fe(II) coordination chemistry of a pyridinophane tren-derived scorpiand type ligand containing a pyridine ring in the pendant arm is explored by potentiometry, X-ray, NMR, and kinetics methods. Equilibrium studies in water show the formation of a stable [FeL](2+) complex that converts to monoprotonated and monohydroxylated species when the pH is changed. A [Fe(H-2L)](2+) complex containing an hexacoordinated dehydrogenated ligand has been isolated, and its crystal structure shows the formation of an imine bond involving the aliphatic nitrogen of the pendant arm...
March 24, 2017: Inorganic Chemistry
https://www.readbyqxmd.com/read/28338296/photochromism-and-dual-color-fluorescence-in-a-polyoxometalate-benzospiropyran-molecular-switch
#19
Arnaud Parrot, Aurélie Bernard, Aurélie Jacquart, Stefano Artin Serapian, Carles Bo, Etienne Derat, Olivier Oms, Anne Dolbecq, Anna Proust, Rémi Métivier, Pierre Mialane, Guillaume Izzet
The photophysical properties of a Keggin-type polyoxometalate (POM) covalently bounded to a benzospiropyran (BSPR) unit have been investigated. These studies reveal that both closed and open forms are emissive with distinct spectral features (λem (closed form)=530 nm, λem (open form)=670 nm) and that the fluorescence of the BSPR unit of the hybrid is considerably enhanced compared to BSPR parent compounds. While the fluorescence excitation energy of the BSPR reference compounds (370 nm) is close to the intense absorption responsible of the photochromic character (350 nm), the fluorescence excitation of the hybrid is shifted to lower energy (400 nm), improving the population of the emissive state...
March 24, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28338246/insights-into-trans-ligand-and-spin-orbit-effects-on-electronic-structure-and-ligand-nmr-shifts-in-transition-metal-complexes
#20
Anja H Greif, Peter Hrobarik, Martin Kaupp
Surprisingly general effects of trans ligands L on the ligand NMR shifts in 5d complexes have been found by quasirelativistic computations, encompassing 5d10, 5d8, and to some extent even 5d6 situations. Closer analysis, with emphasis on 1H shieldings in a series of linear H AuI Lq complexes, reveals a dominance of spin-orbit (SO) effects, which can change sign from appreciably shielding for weak trans ligands to appreciably deshielding for ligands with strong trans influence. This could be traced back to increasing destabilization of a -type MO at scalar relativistic level, which translates into very different -/-mixing if SO coupling is included...
March 24, 2017: Chemistry: a European Journal
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