scholarly journals Synthesis and Structure of Novel Potentially Bioactive Amphiphilic -O-(N)-Glycosides

2020 ◽  
Vol 3 (1) ◽  
pp. 100
Author(s):  
Natividad Bejarano ◽  
Leticia Lafuente ◽  
Juliana Esteche ◽  
Cintia C. Santiago ◽  
Agustín H. Rojas ◽  
...  
Keyword(s):  
Double Bond ◽  
Structural Analysis ◽  
Spectroscopic Analysis ◽  
Straightforward Manner ◽  
Biphasic Reaction

Herein we present the synthesis and structural analysis of novel -O-(N)-glycosides. The biphasic reaction of NHS and acetobromo-α-d-glucose or d-galactose gives the β anomer glycoside in a straightforward manner. Further hydrazinolysis and condensation with decanal afforded the desired products. Their complete structures, including the anomeric and E/Z double bond configurations, were determined by spectroscopic analysis.

scholarly journals IR analysis of the carboxylate forms in structurally determined [CuII(κ3-L)2] species isolated from different acidic solutions

2015 ◽  
Vol 34 (1) ◽  
pp. 133 ◽  
Author(s):  
Bojan Kozlevčar ◽  
Marta Počkaj ◽  
Nives Kitanovski
Keyword(s):  
Double Bond ◽  
Structural Analysis ◽  
Free Ligand ◽  
Double Bond Position ◽  
Molecular Structures ◽  
Acidic Solutions ◽  
Lower Energy Region ◽  
Crystal Structural ◽  
Ir Analysis ◽  
Split Band

Several copper(II) coordination compounds with the tridentate κ<sup>3</sup>-<em>N,N,O</em> bisligand (L = bis(3,5-dimethylpyrazol-1-yl)acetate or its molecular acid form HL = Hbdmpza) were synthesized from different starting metal salts in appropriate acidic water solutions as reported. The XRD single crystal structural analysis reveals neutral acidic ligand form in [Cu(HL)<sub>2</sub>]·2(HSO<sub>4</sub>) (<strong>1</strong>) and [Cu(HL)<sub>2</sub>]·2Cl (<strong>2</strong>), while ionic in [Cu(L)<sub>2</sub>]·(CH<sub>3</sub>COOH)·(H<sub>2</sub>O) (<strong>3</strong>), and [Cu(L)<sub>2</sub>]·2(H<sub>2</sub>O) (<strong>4</strong>). The molecular structures of <strong>2</strong> and <strong>3 </strong>are first reported herein, thus enabling a clearer insight for the IR - structural analysis. Two carboxylate C-O bond lengths ranges, namely differing 1.29/1.22 Ǻ for <strong>2</strong>, and the same 1.24/1.24 Ǻ for <strong>3</strong>, respectively, are in agreement with the single(longer)/double(shorter) character of both bonds for the neutral carboxylic  HL in <strong>2</strong>, and the same character of both bonds for the carboxylate anionic L<sup>-</sup> in <strong>3</strong>, as seen for the related <strong>1 </strong>(HL) and <strong>4 </strong>(L<sup>-</sup>). The most distinguished IR spectra difference for the molecular (HL) / ionic (L<sup>-</sup>) is at the 1700 cm<sup>-1</sup> carboxylate band. The C=O free ligand (HL) double bond position at 1740 cm<sup>-1</sup> is most similar with 1702 cm<sup>-1</sup> in <strong>1</strong>,<strong> </strong>while a split band at 1697, 1665 cm<sup>-1</sup> is seen for <strong>2</strong>. On the other hand, the anionic asymmetric carboxylate stretching IR band (<strong>`</strong>n<sub>as</sub>(COO<sup>−</sup>)) for <strong>3</strong> (1642 cm<sup>-1</sup>) and <strong>4 </strong>(1635 cm<sup>-1</sup>) is found at lower energy region. Thus, the additional band within the same region, as seen only for <strong>3 </strong>at 1716 cm<sup>-1</sup>, is assigned to the network neutral acetic acid C=O double bond.

Sigmosceptrins A - C: New Norditerpenes from a Southern Australian Marine Sponge, Sigmosceptrella sp.

1997 ◽  
Vol 50 (12) ◽  
pp. 1137 ◽  
Author(s):  
Sean Bassett, ◽  
Simon P. B. Ovenden ◽  
Robert W. Gable ◽  
Robert J. Capon
Keyword(s):  
Structural Analysis ◽  
Single Crystal ◽  
Ethyl Ester ◽  
Marine Sponge ◽  
Biosynthetic Pathway ◽  
Spectroscopic Analysis ◽  
Methyl Esters ◽  
Chemical Degradation ◽  
X Ray ◽  
Great Australian Bight

A Sigmosceptrella sp. of sponge collected during trawling operations in the Great Australian Bight, Australia, has yielded a series of new norterpenes. These include a new bisnorditerpene, sigmosceptrin-A (5); two new norditerpenes, sigmosceptrin-B (14) and sigmosceptrin-C (15), isolated as their methyl esters (6) and (7) respectively; and an ethylated artefact, sigmosceptrin-B ethyl ester (8). Complete stereostructures were assigned to the sigmosceptrins by spectroscopic analysis, chemical degradation, derivatization, and by a single-crystal X-ray structural analysis. A biosynthetic pathway is proposed that requires a common biosynthetic precursor to both the sigmosceptrins and norterpene cyclic peroxides.

Novel paper sizing agents based on renewables. Part 5: characterization of maleated oleates by ozonolysis

Holzforschung ◽  
2012 ◽  
Vol 66 (1) ◽  
Author(s):  
Elisabeth Lackinger ◽  
Jürgen Sartori ◽  
Antje Potthast ◽  
Thomas Rosenau
Keyword(s):  
Oleic Acid ◽  
Double Bond ◽  
Structural Analysis ◽  
Molecular Fragments ◽  
Acid Moiety ◽  
High Oleic Sunflower Oil ◽  
High Oleic ◽  
Paper Sizing ◽  
Sizing Agents

Abstract Maleated high oleic sunflower oil (maleated SOHO, MSOHO) is a promising substitute for alkenyl succinic anhydrides (ASA) that are widely used as sizing agents for paper. The part of the MSOHO molecule that is believed to be responsible for adhesion of the molecule onto cellulose, i.e., the maleated oleic acid moiety, was separately prepared and analytically characterized. Structural analysis was completed by studies of the molecular fragments obtained upon ozonolysis. The interesting question of whether there was a preferential reactivity during the ene-reaction of maleic anhydride with oleates was answered in a way that the newly formed double bond was placed to either side with no apparent selectivity.

scholarly journals Synthesis and Antimicrobial Activities of Some Sulphur Containing Chromene Derivatives

2012 ◽  
Vol 7 (7) ◽  
pp. 1934578X1200700
Author(s):  
Tuba Şerbetçi ◽  
Seher Birteksöz ◽  
Soizic Prado ◽  
Sylvie Michel ◽  
François Tillequin
Keyword(s):  
Antimicrobial Activity ◽  
Double Bond ◽  
Spectroscopic Analysis ◽  
Antimicrobial Activities ◽  
Cyclic Carbonate

A series of 3,3-dimethyl-3 Hbenzothieno[3,2- f][1]-benzopyran analogues modified at the pyran 1,2-double bond were synthesized. The corresponding dihydro and (±)-cis-diol derivatives were converted into diacetate and cyclic carbonate upon acylation. The title compounds were characterized by spectroscopic analysis and screened for their antimicrobial activity in vitro.

scholarly journals Uncovering the origin of Z-configured double bonds in polyketides: intermediate E-double bond formation during borrelidin biosynthesis

2014 ◽  
Vol 5 (9) ◽  
pp. 3563-3567 ◽  
Author(s):  
Nadine Kandziora ◽  
Jennifer N. Andexer ◽  
Steven J. Moss ◽  
Barrie Wilkinson ◽  
Peter F. Leadlay ◽  
...  
Keyword(s):  
Double Bond ◽  
Spectroscopic Analysis ◽  
Bond Formation ◽  
Double Bonds

The dehydratase domain BorDH3 is assayed with a synthetic surrogate of the predicted tetraketide substrate and shown to be E-selective. Detailed NMR spectroscopic analysis of pre-borrelidin assigns the timing of the E-5 Z-isomerization to the very final steps of borrelidin biosynthesis.

Construction of a Corpus of Rhetorical Devices in Slogans and Structural Analysis of Antitheses

2021 ◽  
Vol 20 (6) ◽  
pp. 1-26
Author(s):  
Ayana Niwa ◽  
Naoaki Okazaki ◽  
Kohei Wakimoto ◽  
Keisuke Nishiguchi ◽  
Masataka Mouri
Keyword(s):  
Structural Analysis ◽  
Prediction Accuracy ◽  
Sentence Structure ◽  
Lexical Knowledge ◽  
Straightforward Manner ◽  
Work Of Art ◽  
Rhetorical Devices ◽  
Comparable Method ◽  
Lexical Constraints ◽  
Large Corpus

An advertising slogan is a sentence that expresses a product or a work of art in a straightforward manner and is used for advertising and publicity. Moving the consumer's mind and attracting their interest can significantly influence sales. Although rhetorical techniques in a slogan are known to improve the effectiveness of advertising, not much attention has been devoted to analyze or automatically generate sentences with the techniques. Therefore, we constructed a large corpus of slogans and revealed the linguistic characteristics of the basic statistics and rhetorical devices. Another point of focus was antitheses, of which the usage rates are relatively high and which have a specific sentence structure and lexical constraints. The generation of a slogan that contains an antithesis necessitates the structure of sentences, known as templates, to be extracted and also requires knowledge of word pairs with semantic contrast. Thus, the next step involved analysis of the structure to extract the sentence structure and lexical knowledge about the antithesis. Despite its simple architecture, the proposed method exceeds the prediction accuracy and efficiency of a comparable method. Lexical knowledge that is not available in existing dictionaries was also extracted.

scholarly journals Solid state linear-dichroic infrared (IR-LD) spectroscopic characterization of α-and β-glycine polymorphs

2006 ◽  
Vol 4 (1) ◽  
pp. 111-117 ◽  
Author(s):  
Bojidarka Ivanova
Keyword(s):  
Liquid Crystal ◽  
Solid State ◽  
Structural Analysis ◽  
Nematic Liquid Crystal ◽  
Spectroscopic Analysis ◽  
Spectroscopic Characterization ◽  
State Orientation ◽  
Orientation Technique

AbstractIR-LD spectroscopic analysis using nematic liquid crystal suspension as a solid-state orientation technique and the reducing-difference procedure for polarized spectra interpretation are applied to the α-and β-polymorphs of glycine. Both structural analysis and detailed IR band assignments were carried out.

scholarly journals The Development and Application of Novel IR and NMR-Based Model for the Evaluation of Carminative Effect ofArtemisia judaicaL. Essential Oil

2014 ◽  
Vol 2014 ◽  
pp. 1-10 ◽  
Author(s):  
Muhammed Alzweiri ◽  
Ibrahim M. Alrawashdeh ◽  
Sanaa K. Bardaweel
Keyword(s):  
Infrared Spectroscopy ◽  
Nmr Spectroscopy ◽  
Structural Analysis ◽  
Surface Activity ◽  
Spectroscopic Analysis ◽  
Oil Composition ◽  
H Nmr ◽  
First Derivative ◽  
Chloroform Layer ◽  
Precision And Accuracy

Artemisia judaicaL. is a medicinal plant that is traditionally used to relieve abdominal pains through its carminative activity. In this study, spectroscopic analysis was employed to investigate the carminative activity associated withA. judaica. Using infrared spectroscopy, the carminative activity was evaluated based on the first derivative of IR-characteristic stretching signal of CO2. Our results indicate thatA. judaicaoil effectively reduced the response of CO2signal equivalent to thymol standard. Additionally,1H-NMR spectroscopy was utilized to assess surface activity ofA. judaicacrude oil through the reduction of interfacial tension in a D2O/CDCl3system. Apparently, 10 mg of the oil was able to solubilize water in a chloroform layer up to 4.3% (w/w). In order to correlate the observed surface activity of the oil to its actual composition, GC-MS and GC-FID structural analysis were undertaken. The results revealed that the oil composition consists of oxygenated terpenes which might be responsible for the carminative effect. Furthermore, owing to its sensitivity, our model provides a fundamental basis for the pharmacological assessment of trace amounts of oils with high precision and accuracy.

Structural analysis of the surface-layer protein of spirillum serpens by high-resolution electron microscopy

1983 ◽  
Vol 41 ◽  
pp. 738-739
Author(s):  
W. H. Wu ◽  
R. M. Glaeser
Keyword(s):  
Electron Microscopy ◽  
Surface Layer ◽  
Structural Analysis ◽  
High Resolution ◽  
Low Dose ◽  
High Resolution Electron Microscopy ◽  
Optical Diffraction ◽  
Surface Layer Protein ◽  
Morphological Unit ◽  
Resolution Electron

Spirillum serpens possesses a surface layer protein which exhibits a regular hexagonal packing of the morphological subunits. A morphological model of the structure of the protein has been proposed at a resolution of about 25 Å, in which the morphological unit might be described as having the appearance of a flared-out, hollow cylinder with six ÅspokesÅ at the flared end. In order to understand the detailed association of the macromolecules, it is necessary to do a high resolution structural analysis. Large, single layered arrays of the surface layer protein have been obtained for this purpose by means of extensive heating in high CaCl2, a procedure derived from that of Buckmire and Murray. Low dose, low temperature electron microscopy has been applied to the large arrays.As a first step, the samples were negatively stained with neutralized phosphotungstic acid, and the specimens were imaged at 40,000 magnification by use of a high resolution cold stage on a JE0L 100B. Low dose images were recorded with exposures of 7-9 electrons/Å2. The micrographs obtained (Fig. 1) were examined by use of optical diffraction (Fig. 2) to tell what areas were especially well ordered.

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