Spectroscopic manifestation of stretching vibrations of glycosidic linkage in polysaccharides

The wave numbers of the fundamental C=O and C=C stretching vibrations, as well as that of the first overtone of C=O stretching vibration of 2-(3-, and 4-substituted phenylmethylene)-1,3-cycloheptanediones and 1,3-cycloheptanedione were measured in tetrachloromethane and chloroform. The spectral data were correlated with σ+ constants of substituents attached to phenyl group and with wave number shifts of the C=O stretching vibration of substituted acetophenones. The slope of the linear dependence ν vs ν+ of the C=C stretching vibration of the ethylenic group was found to be more than two times higher than that of the analogous correlation of the C=O stretching vibration. Positive values of anharmonicity for asymmetric C=O stretching vibration can be considered as an evidence of the vibrational coupling in a cyclic 1,3-dicarbonyl system similarly, as with derivatives of 1,3-indanedione. The relationship between the wave numbers of the symmetric and asymmetric C=O stretching vibrations indicates that the effect of structure upon both vibrations is symmetric. The vibrational coupling in 1,3-cycloheptanediones and the application of Seth-Paul-Van-Duyse equation is discussed in relation to analogous results obtained for other cyclic 1,3-dicarbonyl compounds.

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Dipole Moments of para-Substituted N-Phenylsulfonyl-N'-Allylthioureas

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19950856 ◽

1995 ◽

Vol 60 (5) ◽

pp. 856-862

Author(s):

Gejza Suchár ◽

Ivan Danihel

Keyword(s):

Dipole Moments ◽

Vector Addition ◽

Stretching Vibrations

Dipole moments of a series of para-substituted N-phenylsulfonyl-N'-allylthioureas were determined. Comparison of the experimentally found dipole moments with those calculated by vector addition of bond and group moments has shown that (E) conformation at the N-C bonds is preferred. The same result was obtained from the N-H stretching vibrations. The results are compatible with a synperiplanar arrangement at the C-C bond of the allyl moiety.

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Vibrational spectra of aquadioxotetra; peroxodivanadates(V) M2[V2O2(O2)4(H2O)]·xH2O (M = N(CH3)4, Cs)

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19901485 ◽

1990 ◽

Vol 55 (6) ◽

pp. 1485-1490 ◽

Cited By ~ 4

Author(s):

Peter Schwendt ◽

Milan Sýkora

Keyword(s):

Raman Spectra ◽

Vibrational Spectra ◽

Normal Coordinate Analysis ◽

Force Constants ◽

Infrared And Raman Spectra ◽

Empirical Correlations ◽

Normal Coordinate ◽

Bond Lengths ◽

Stretching Vibrations

The infrared and Raman spectra of M2[V2O2(O2)4(H2O)]·xH2O and M2[V2O2(O2)4(D2O)]·xD2O (M = N(CH3)4, Cs) were measured. In the region of the vanadium-oxygen stretching vibrations, the spectra were interpreted based on normal coordinate analysis, employing empirical correlations between the bond lengths and force constants.

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Full-Length Transcriptome of Thalassiosira weissflogii as a Reference Resource and Mining of Chitin-Related Genes

Marine Drugs ◽

10.3390/md19070392 ◽

2021 ◽

Vol 19 (7) ◽

pp. 392

Author(s):

Haomiao Cheng ◽

Chris Bowler ◽

Xiaohui Xing ◽

Vincent Bulone ◽

Zhanru Shao ◽

...

Keyword(s):

Cell Wall ◽

Full Length ◽

Biosynthetic Pathways ◽

Glycosidic Linkage ◽

Thalassiosira Weissflogii ◽

Ecological Value ◽

Pacbio Sequencing ◽

Non Coding Rnas ◽

Chitin And Chitosan ◽

Simple Sequence

β-Chitin produced by diatoms is expected to have significant economic and ecological value due to its structure, which consists of parallel chains of chitin, its properties and the high abundance of diatoms. Nevertheless, few studies have functionally characterised chitin-related genes in diatoms owing to the lack of omics-based information. In this study, we first compared the chitin content of three representative Thalassiosira species. Cell wall glycosidic linkage analysis and chitin/chitosan staining assays showed that Thalassiosira weissflogii was an appropriate candidate chitin producer. A full-length (FL) transcriptome of T. weissflogii was obtained via PacBio sequencing. In total, the FL transcriptome comprised 23,362 annotated unigenes, 710 long non-coding RNAs (lncRNAs), 363 transcription factors (TFs), 3113 alternative splicing (AS) events and 3295 simple sequence repeats (SSRs). More specifically, 234 genes related to chitin metabolism were identified and the complete biosynthetic pathways of chitin and chitosan were explored. The information presented here will facilitate T. weissflogii molecular research and the exploitation of β-chitin-derived high-value enzymes and products.

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The structure of nephritogenoside. A nephritogenic glycopeptide with alpha-N-glycosidic linkage.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)37780-9 ◽

1988 ◽

Vol 263 (25) ◽

pp. 12483-12485

Author(s):

S Shibata ◽

T Takeda ◽

Y Natori

Keyword(s):

Glycosidic Linkage

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Copper(II) 2,2-Bis(Hydroxymethyl)Propionate Coordination Compounds with Hexamethylenetetramine: From Mononuclear Complex to One-Dimensional Coordination Polymer

Molecules ◽

10.3390/molecules26113358 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3358

Author(s):

Sadaf Rauf ◽

Agata Trzesowska-Kruszynska ◽

Tomasz Sierański ◽

Marcin Świątkowski

Keyword(s):

Coordination Polymer ◽

Coordination Compounds ◽

Structural Diversity ◽

Structural Features ◽

Mononuclear Complex ◽

Molar Ratio ◽

One Dimensional ◽

1D Coordination Polymer ◽

Copper Coordination ◽

Stretching Vibrations

Three new copper coordination compounds derived from 2,2-bis(hydroxymethyl)propionic acid (dmpa) and hexamethylenetetramine (hmta) were obtained and their crystal structures were determined. The stoichiometry of the reagents applied in the syntheses reflects the metal to ligand molar ratio in the formed solid products. Due to the multiple coordination modes of the used ligands, wide structural diversity was achieved among synthesized compounds, i.e., mononuclear [Cu(dmp)2(hmta)2(H2O)] (1), dinuclear [Cu2(dmp)4(hmta)2] (2), and 1D coordination polymer [Cu2(dmp)4(hmta)]n (3). Their supramolecular structures are governed by O—H•••O and O—H•••N hydrogen bonds. The compounds were characterized in terms of absorption (UV-Vis and IR) and thermal properties. The relationships between structural features and properties were discussed in detail. Owing to discrepancies in the coordination mode of a dmp ligand, bidentate chelating in 1, and bidentate bridging in 2 and 3, there is a noticeable change in the position of the bands corresponding to the stretching vibrations of the carboxylate group in the IR spectra. The differences in the structures of the compounds are also reflected in the nature and position of the UV-Vis absorption maxima, which are located at lower wavelengths for 1.

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