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alkyl glycerol

D Vollhardt, G Brezesinski
The effect of chirality on the thermodynamic behavior, the morphological features, and the 2D lattice structures of 3-monostearoyl-sn-glycerol monolayers is studied. The present study focusses on the influence of the alkyl chain length on the chiral discrimination. Surface pressure-area (π-A) isotherms, Brewster angle microscopy (BAM), and particularly, grazing incidence X-ray diffraction (GIXD) are the experimental basis of the presented results. The π-A isotherms of the enantiomeric 3-monostearoyl-sn-glycerol monolayers measured between 25 and 38 °C resemble those of the racemic 1-monostearoyl-rac-glycerol monolayers, thus indicating small energetic differences between the enantiomeric and the racemic forms...
February 28, 2017: Physical Chemistry Chemical Physics: PCCP
Carme Huguet, Susanne Fietz, Antoni Rosell-Melé, Xavier Daura, Lionel Costenaro
Archaeal tetraether membrane lipids span the whole membrane width and present two C40 isoprenoid chains bound by two glycerol groups (or one glycerol and calditol). These lipids confer stability and maintain the membrane fluidity in mesophile to extremophile environments, making them very attractive for biotechnological applications. The isoprenoid lipid composition in archaeal membranes varies with temperature, which has placed these lipids in the focus of paleo-climatological studies for over a decade. Non-hydroxylated isoprenoid archaeal lipids are typically used as paleo-thermometry proxies, but recently identified hydroxylated (OH) derivatives have also been proposed as temperature proxies...
February 16, 2017: Biochimica et Biophysica Acta
Zhengfei Chen, Michael Ludwig, Gregory G Warr, Rob Atkin
Deep eutectic solvents (DESs) have been prepared from mixtures of alkyl ammonium bromide salts (ethylammonium bromide, propylammonium bromide and butylammonium bromide) and glycerol at a 1: 2 M ratio. These DESs reveal the effect of cation alkyl chain length on interfacial structure at mica (a model anionic) surface. As the cation chain length is increased it becomes more amphiphilic and solvophobic, leading to stronger association of alkyl chains, as revealed by atomic force microscope force curve measurements...
May 15, 2017: Journal of Colloid and Interface Science
Lisa Cattelan, Alvise Perosa, Piero Riello, Thomas Maschmeyer, Maurizio Selva
The base-catalysed reactions of OH-bearing biobased derivatives (BBDs) including glycerol formal, solketal, glycerol carbonate, furfuryl alcohol and tetrahydrofurfuryl alcohol with non-toxic dialkyl carbonates (dimethyl and diethyl carbonate) were explored under continuous-flow (CF) conditions in the presence of three Na-exchanged Y- and X-faujasites (FAUs) and four Mg-Al hydrotalcites (HTs). Compared to previous etherification protocols mediated by dialkyl carbonates, the reported procedure offers substantial improvements not only in terms of (chemo)selectivity but also for the recyclability of the catalysts, workup, ease of product purification and, importantly, process intensification...
January 31, 2017: ChemSusChem
Sergio Alberto Bernal-Chávez, Lilia Yazmín Pérez-Carreto, María Guadalupe Nava-Arzaluz, Adriana Ganem-Rondero
The absorption modulating activity of two alkylglycerol derivatives (batyl and chimyl alcohol) on skin barrier properties was evaluated. Biophysical tests such as transepidermal water loss (TEWL) and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, as well as in vitro skin permeation studies, were performed in order to determine the effect of these compounds as chemical absorption modulators. Four drugs were used as models: three NSAIDS (diclofenac, naproxen, and piroxicam) and glycyrrhizic acid...
January 22, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Alice Luddi, Martina Gori, Laura Crifasi, Camilla Marrocco, Giuseppe Belmonte, Elvira Costantino-Ceccarini, Paola Piomboni
Spermatogenesis is a complex process of proliferation and differentiation during male germ cell development whereby undifferentiated spermatogonial germ cells evolve into maturing spermatozoa. In this developmental process the interactions between different cell types are finely regulated, hence any disruption in these relationships leads to male infertility. The twitcher mouse, the murine model of Krabbe disease, is characterized by deficiency of galactosylceramidase, an enzyme also involved in the metabolism of the galactosyl-alkyl-acyl-glycerol, the precursor of sulfogalactosyl-alkyl-acyl-glycerol, the most abundant glycolipid in spermatozoa...
April 2017: Systems Biology in Reproductive Medicine
Shigeo Takashima, Kayoko Toyoshi, Takahiro Itoh, Naomi Kajiwara, Ayako Honda, Akiko Ohba, Shoko Takemoto, Satoshi Yoshida, Nobuyuki Shimozawa
Metabolic changes occur in patients with peroxisomal diseases owing to impairments in the genes involved in peroxisome function. For diagnostic purposes, saturated very-long-chain fatty acids (VLCFAs) such as C24:0 and C26:0, phytanic acid, pristanic acid, and plasmalogens are often measured as metabolic hallmarks. As the direct pathology of peroxisomal disease is yet to be fully elucidated, we sought to explore the fatty acid species that accumulate in patients with peroxisomal diseases. We developed a method for detecting a range of fatty acids implicated in peroxisomal diseases such as Zellweger syndrome (ZS) and X-linked adrenoleukodystrophy (X-ALD)...
March 2017: Molecular Genetics and Metabolism
Jung Eun Jang, Han-Sol Park, Hyun Ju Yoo, In-Jeoung Baek, Ji Eun Yoon, Myoung Seok Ko, Ah-Ram Kim, Hyoun Sik Kim, Hye-Sun Park, Seung Eun Lee, Seung-Whan Kim, Su Jung Kim, Jaechan Leem, Yu Mi Kang, Min Kyo Jung, Chan-Gi Pack, Chong Jai Kim, Chang Ohk Sung, In-Kyu Lee, Joong-Yeol Park, José C Fernández-Checa, Eun Hee Koh, Ki-Up Lee
Free cholesterol (FC) accumulation in the liver is an important pathogenic mechanism of nonalcoholic steatohepatitis (NASH). Plasmalogens, key structural components of the cell membrane, act as endogenous antioxidants and are primarily synthesized in the liver. However, the role of hepatic plasmalogens in metabolic liver disease is unclear. In this study, we found that hepatic levels of docosahexaenoic acid (DHA)-containing plasmalogens, expression of glyceronephosphate O-acyltransferase (Gnpat, the rate-limiting enzyme in plasmalogen biosynthesis), and expression of Pparα were lower in mice with NASH caused by accumulation of free cholesterol (FC) in the liver...
January 10, 2017: Hepatology: Official Journal of the American Association for the Study of Liver Diseases
Rong-Juan Feng, Xia Li, Zhen Zhang, Zhou Lu, Yuan Guo
The interfacial behavior of the benchmark zwitterionic phospholipid molecule dipalmitoylphosphatidylcholine (DPPC) has been extensively investigated by surface-selective vibrational sum frequency generation spectroscopy (VSFG). However, there is still a lack of agreement between various orientational measurements of phospholipid monolayers at the air/water interface, mainly because of the difficulty in assigning congested VSFG features. In this study, polarization-dependent VSFG measurements reveal a frequency shift between the in-plane and out-of-plane antisymmetric stretching modes of the terminal methyl groups in the DPPC alkyl tails, favoring the model of Cs local symmetry rather than the previously assumed C3v symmetry...
December 28, 2016: Journal of Chemical Physics
Birte Martin-Bertelsen, Anan Yaghmur, Henrik Franzyk, Sarah Justesen, Jacob J K Kirkensgaard, Camilla Foged
Synthetic analogues of the cell-wall lipid monomycoloyl glycerol (MMG) are promising as next-generation vaccine adjuvants. In the present study, the thermotropic phase behavior of an array of synthetic MMG analogues was examined by using simultaneous small- and wide-angle X-ray scattering under excess water conditions. The MMG analogues differed in the alkyl chain lengths and in the stereochemistry of the polar glycerol headgroup or of the lipid tails (native-like versus alternative compounds). All MMG analogues formed poorly hydrated lamellar phases at low temperatures and inverse hexagonal (H2) phases at higher temperatures prior to melting...
December 6, 2016: Langmuir: the ACS Journal of Surfaces and Colloids
Cristian Vidal, Joaquín García-Álvarez, Alberto Hernán-Gómez, Alan R Kennedy, Eva Hevia
Shattering the long-held dogma that organolithium chemistry needs to be performed under inert atmospheres in toxic organic solvents, chemoselective addition of organolithium reagents to non-activated imines and quinolines has been accomplished in green, biorenewable deep eutectic solvents (DESs) at room temperature and in the presence of air, establishing a novel and sustainable access to amines. Improving on existing methods, this approach proceeds in the absence of additives; occurs without competitive enolization, reduction or coupling processes; and reactions were completed in seconds...
December 23, 2016: Angewandte Chemie
Marta Rodríguez-Rodríguez, Patricia Llanes, Christian Pradel, Miquel A Pericàs, Montserrat Gómez
The effect of long-alkyl-chain amines in CuI-assisted azide-alkyne cycloadditions of terminal alkynes with organic azides in glycerol and other environmentally benign solvents (water, ethanol) has been examined. The presence of these additives favors the in situ formation of Cu(I) -based nanoparticles and results in an increase of the catalytic reactivity. In glycerol, liquid-phase transmission electron microscopy (TEM) analyses, enabled by the negligible vapor pressure of this solvent, proved that Cu(I) nanoparticles are responsible for the observed catalytic activity...
December 12, 2016: Chemistry: a European Journal
Ekaterina Ermolenko, Nikolay Latyshev, Ruslan Sultanov, Sergey Kasyanov
Biological active compounds, 1-O-alkyl-sn-glycerols (AG), were isolated from liver oil of the squid Berryteuthis magister. The main components of the initial lipids were 1-O-alkyl-2,3-diacyl-sn-glycerols (38.50 %) and triacylglycerols (24.26 %). The first step of separation was the alkaline hydrolysis of oil to form a lipid mixture consisting of AG, free fatty acids and cholesterol. AG were separated by double recrystallization from acetone at -20 °C and 1 °C. A simple procedure is proposed for obtaining AG with a purity of 99...
March 2016: Journal of Food Science and Technology
T A Foglia, K Maeda
The resolution of a series of racemic 1-alkyl-3-trityl-rac-glycerols and 1-alkyl-2-benzyl-rac-glycerols into their enantiomers by high-performance liquid chromatography (HPLC) was investigated. Of the racemic glycerol derivatives studied, only three (1,2-0-isopropylidene-rac-glycerol, 1,2-0-isopropylidene-3-benzyl-rac-glycerol and 1-hexadecyl-2-benzyl-rac-glycerol) could be resolved into their enantiomers. The compounds were resolved on a silica (10 μm) column coated with cellulose tribenzoate and eluted isocratically with hexane/isopropanol as mobile phase...
September 1991: Lipids
W J Hansen, R Murari, Y Wedmid, W J Baumann
Choline phospholipids can be conveniently synthesized by reaction of a lipophilic alcohol, such as diacylglycerol, with 2-bromoethyl dichlorophosphate followed by nucleophilic displacement of the bromine with trimethylamine. We found that the low yields often encountered in the initial phosphorylation step are particularly due to exchange of both chlorines for alkoxy functions (triester formation) and to chlorination of the alcohol by 2-bromoethyl dichlorophosphate. However, these drawbacks can be overcome by proper choice of the reaction medium and by optimizing other reaction conditions...
June 1982: Lipids
A Poulos, G A Thompson
The in vivo incorporation of 1-(14)C-palmitic acid and 1-0-[8,9-(3)H] hexadecyl glycerol (chimyl alcohol) by plasmodia of the slime mold,Physarum polycephalum has been studied.(14)C-palmitate rapidly enters ester and alkyl ether side chains of phospholipids, but alk-1-enyl side chains are labeled more slowly.(3)H-chimyl alcohol is incorporated into the alkyl ether phospholipids, which appear to undergo enzymatic desaturation, producing plasmalogens. The feasibility ofPhysarum as the source of a cell-free enzyme system for plasmalogen synthesis is discussed...
July 1971: Lipids
Birte Martin-Bertelsen, Karen S Korsholm, Carla B Roces, Maja H Nielsen, Dennis Christensen, Henrik Franzyk, Anan Yaghmur, Camilla Foged
The mycobacterial cell-wall lipid monomycoloyl glycerol (MMG) is a potent immunostimulator, and cationic liposomes composed of a shorter synthetic analogue (MMG-1) and dimethyldioctadecylammonium (DDA) bromide represent a promising adjuvant that induces strong antigen-specific Th1 and Th17 responses. In the present study, we investigated the supramolecular structure and in vivo adjuvant activity of dispersions based on binary mixtures of DDA and an array of synthetic MMG-1 analogues (MMG-2/3/5/6) displaying longer (MMG-2) or shorter (MMG-3) alkyl chain lengths, or variations in stereochemistry of the polar headgroup (MMG-5) or of the hydrophobic moiety (MMG-6)...
August 1, 2016: Molecular Pharmaceutics
D Vollhardt, G Brezesinski
1-Monopalmitoyl-rac-glycerol is omnipresent in numerous biological and applied systems. Systematic GIXD measurements of 1-monopalmitoyl-rac-glycerol monolayers are carried out over a large pressure interval at 5, 10, and 15 °C to construct the phase diagram on the basis of reliable 2D lattice structures. These studies are complemented by other monolayer characteristics, such as π-A isotherms and mesoscopic domain topographies. A phase transition is found between the two orthorhombic structures with NN and NNN tilted alkyl chains at low temperatures (5 and 10 °C)...
July 26, 2016: Langmuir: the ACS Journal of Surfaces and Colloids
Camille Delude, Laetitia Fouillen, Palash Bhar, Marie-Josée Cardinal, Stephanie Pascal, Patricia Santos, Dylan K Kosma, Jérôme Joubès, Owen Rowland, Frédéric Domergue
Suberin is a complex hydrophobic polymer that acts as a barrier controlling water and solute fluxes and restricting pathogen infections. Suberin is deposited immediately outside of the plasmalemma in the cell wall of certain tissues such as endodermis of roots, aerial and underground periderms, and seed coats. Suberin consists of a variety of fatty acid derivatives polymerized with glycerol and phenolics. In this study, we show using liquid chromatography-tandem mass spectrometry and gas chromatography-mass spectrometry techniques that most of the fatty alcohols not covalently linked to the suberin polymer are in the form of alkyl hydroxycinnamates (AHCs), with alkyl caffeates predominating...
July 2016: Plant Physiology
Xiuniang Tan, Jianling Zhang, Tian Luo, Xinxin Sang, Chengcheng Liu, Bingxing Zhang, Li Peng, Wei Li, Buxing Han
The aggregation behavior of the ionic liquid (IL) 1-alkyl-3-methylimidazolium chloride with different alkyl chain lengths in a deep eutectic solvent (DES, composed of choline chloride and glycerol in a 1 : 2 mole ratio) was studied for the first time. The critical micellar concentration, micellar size and intermolecular interactions in IL/DES solutions were investigated by different techniques including the fluorescence probe technique, small angle X-ray scattering and Fourier transform infrared spectroscopy...
June 28, 2016: Soft Matter
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