Structural features of a central mismatch in oligonucleotide hybrid duplexes visualized via Raman spectroscopy: Model system for evaluation of potential “antisense” drugs

We analyzed the structural features of C1q that underlie its autoantigenicity by the means of a model system using an amphiphilic polyzwitterion (PZ).

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4,6-Dicarba-8-thia-arachno-nonaborane(10) Revisited. Theoretical Refinement of Its Structure

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19990993 ◽

1999 ◽

Vol 64 (6) ◽

pp. 993-1000 ◽

Cited By ~ 9

Author(s):

Drahomír Hnyk ◽

Matthias Hofmann ◽

Paul von Ragué Schleyer

Keyword(s):

Raman Spectroscopy ◽

Ab Initio ◽

Chemical Shifts ◽

Structural Features ◽

Ir And Raman Spectroscopy ◽

Nmr Method ◽

Ir And Raman ◽

Rule Out

The structure of the nine-vertex arachno-thiadicarbaborane C2SB6H10 has been established employing the ab initio/IGLO/NMR method. Theoretical IGLO 11B chemical shifts support C and S atom placements at the 4, 6 and 8 positions, respectively, and unambiguously rule out the 4,6,5-C2SB6H10 structural alternative, suggested earlier on the basis of IR and Raman spectroscopy. Important structural features of the 4,6,8-C2SB6H10 geometry include a small B(7)-S(8)-B(9) angle (MP2(fc)/6-31G*: 97.9°) and long S-B bonds (MP2(fc)/6-31G*: 1.905 and 1.924 Å) compared to B-B bonds spanning the 1.71-1.85 Å range.

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Syntheses and molecular structures of some di(amidino)monosilanes

Main Group Metal Chemistry ◽

10.1515/mgmc-2021-0024 ◽

2021 ◽

Vol 44 (1) ◽

pp. 228-238

Author(s):

Markus Bös ◽

Marcus Herbig ◽

Uwe Böhme ◽

Edwin Kroke

Keyword(s):

Raman Spectroscopy ◽

Single Crystal ◽

High Field ◽

Structural Features ◽

Molecular Structures ◽

X Ray Diffraction ◽

One Pot ◽

X Ray ◽

Field Shift ◽

Nmr Signals

Abstract The syntheses of three different amidinosilanes of the type Me2Si[N=C(Ph)R]2 with R = pyrrolidino, morpholino, and diethylamino and one derivative with the composition R2Si[N=C(Ph)R]2 with R = morpholino are reported. These compounds were prepared in one-pot syntheses including three consecutive steps. All products are analysed by single crystal X-ray diffraction, NMR, and Raman spectroscopy. The Si–N=C–N units of these compounds show characteristic structural features and cause a significant high field shift of the 29Si NMR signals.

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Raman Spectroscopy Analysis of Nitrogen Ion Implantation in Silicon and Correlation with Transmission Electron Microscopy

MRS Proceedings ◽

10.1557/proc-279-177 ◽

1992 ◽

Vol 279 ◽

Author(s):

A. PéRez-Rodríguez ◽

A. Romano-Rodríguez ◽

J. R. Morante ◽

J. Esteve ◽

J. Montserrat

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Raman Spectroscopy ◽

Raman Spectra ◽

Annealing Treatment ◽

Structural Features ◽

Spectroscopy Analysis ◽

Subsurface Region ◽

Transmission Electron ◽

Nitrogen Ion

ABSTRACTIn this work Si samples implanted with nitrogen (N+ or N2+) at a dose of 1017 cm−2 are characterized by Raman spectroscopy and cross section transmission electron microscopy (XTEM). The correlation between the Raman spectra obtained with different excitation wavelengths and XTEM observations allows to determine the structural features related to the layers contributing to the total spectra. The evolution of these features with the annealing treatments (up to 1150°C) is studied. The results obtained show, after the annealing treatment at the highest temperature, the presence of silicon nitride precipitates in the silicon subsurface region, and the formation of a nitrogen rich polycrystalline Si layer with Si3N4 grains. The Raman spectra from the subsurface region show a remaining shift of -0.15 cm−1 when compared to the spectra from unimplanted Si. This shift, together with the similar shape of both Raman lines, suggests the presence in this region of an average tensile stress of 37.5 MPa.

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Chemical Composition and Biological Activity of Paris quadrifolia L.

Zeitschrift für Naturforschung C ◽

10.1515/znc-2012-11-1206 ◽

2012 ◽

Vol 67 (11-12) ◽

pp. 565-570 ◽

Cited By ~ 1

Author(s):

Kristina Jenett-Siems ◽

Nadin Krause ◽

Karsten Siems ◽

Sven Jakupovic ◽

Gerd Wallukat ◽

...

Keyword(s):

Biological Activity ◽

Chemical Composition ◽

Structural Features ◽

Model System ◽

Cardiac Cells ◽

Steroidal Saponin ◽

Cellular Model ◽

Potential Influence ◽

Plant Compounds

A study of the components of Paris quadrifolia was undertaken to identify compounds with potential influence on cardiac cells, since previous reports suggested a cardiotoxic risk of this plant. Compounds isolated and identified included one new steroidal saponin, (23S,24S)- spirosta-5,25(27)-diene-1β,3β,21,23,24-pentol-1-O-β-D-apiofuranosyl-(1→3)-α-L-rhamnopyranosyl-( 1→2)-[β-D-xylopyranosyl-(1→3)]-β-D-glucopyranoside 21- O- β- D- apiofuranoside 24-O-β-D-fucopyranoside (1), demonstrating quite unusual structural features, as well as the known compounds 26-O-β-D-glucopyranosyl-(25R)-5-en-furost-3β,17α,22α,26-tetraol- 3- O- α- L- rhamnopyranosyl-(1→4)-α-L-rhamnopyranosyl-(1→4)-[α-L-rhamnopyranosyl - -(1→2)]- β- D- glucopyranoside (2), pennogenin 3-O-α-L-rhamnopyranosyl-(1→4)-α-L-rhamno pyranosyl- (1→4)-[α-L-rhamnopyranosyl-(1→ 2)]-β -D- glucopyranoside (3), 7- O- β- D-glucopyranosyl- kaempferol-3- O- β- D-glucopyranosyl-(1→2)-β- D-galactopyranoside (4), kaem pferol- 3-O-β-D-glucopyranosyl-(1→2)-β-D-galactopyranoside (5), 5-hydroxyecdysterone (6), and 20-hydroxyecdysone (7). The pennogenin derivative 3 showed strong cardiotoxic effects in an in vitro cellular model system, whereas the respective furostanol derivative 2 was inactive.

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Raman spectroscopy of tris-(hydroxymethyl)aminomethane as a model system for the studies of α-chymotrypsin activation by crown ether in organic solvents

Journal of Molecular Structure ◽

10.1016/s0022-2860(03)00020-6 ◽

2003 ◽

Vol 648 (3) ◽

pp. 177-182 ◽

Cited By ~ 8

Author(s):

Nikolai N. Brandt ◽

Andrey Yu. Chikishev ◽

Inna K. Sakodinskaya

Keyword(s):

Raman Spectroscopy ◽

Crown Ether ◽

Organic Solvents ◽

Model System

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Chemical analysis of ice vein μ-environments

Polar Record ◽

10.1017/s0032247411000635 ◽

2011 ◽

Vol 48 (4) ◽

pp. 334-341 ◽

Cited By ~ 3

Author(s):

Robert E. Barletta ◽

Christopher H. Roe

Keyword(s):

Raman Spectroscopy ◽

Model System ◽

Analytical Tool ◽

Triple Junctions ◽

Glacial Ice ◽

Natural Systems ◽

Model Studies ◽

Molecular Anions ◽

Polycrystalline Ice ◽

Anion Type

ABSTRACTIcy environments (glacial ice and sea ice) can be complex ecosystems, supporting a diversity of communities. In particular, the μ-environments in which bacteria and algae are found are poorly understood. One important habitat is the liquid trapped in the ice, either as veins and triple junctions inherent in the ice structure or as liquid inclusions. μ-Raman spectroscopy is an analytical tool with the potential to characterise qualitatively and quantitatively these liquid μ-environments especially with respect to molecular anions such as nitrate, sulphate, bisulphate and MSA. Using a model system for glacial ice, splat-cooled samples were prepared from aqueous solutions of these anions at varying concentrations (50–75 mM total sulphate, 30–200 mM nitrate, and 10–55 mM MSA). Concentrations of these anions in the vein liquid were measured directly and non-destructively at –15 °C using μ-Raman spectroscopy. In agreement with predicted concentrations in glacial ice veins, it was found that typical ionic concentrations in veins are quite high, with mean concentrations ranging from 0.23 M to 3.5 M depending on anion type and initial concentration. For sulphate solutions, it was also possible to measure vein pH's directly. The observed pH in these systems was extremely low, in some cases ~1. The results of these model studies as well as the implications for ice vein concentrations in natural systems of polycrystalline ice are discussed.

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