Saneroite: chemical and structural variations of manganese pyroxenoids with hydrogen bonding in the silicate chain

A set of pyrazole-bridged bis(imidazolium) compounds [H3L1]X2 - [H3 L4]X2 (L1 = 3,5-bis[1-(tert-butyl)imidazolium-1-ylmethyl]-1H-pyrazole; L2 = 3,5-bis[1-(tert-butyl)imidazolium- 1-ylmethyl]-4-phenyl-1H-pyrazole; L3 = 3,5-bis[1-(1-adamantyl)imidazolium-1-ylmethyl]-1Hpyrazole; L4 = 3,5-bis[1-(1-adamantyl)imidazolium-1-ylmethyl]-4-phenyl-1H-pyrazole; X = Cl−, BF4 − or PF6 −) has been prepared, and three compounds have been characterized by X-ray crystallography. The unique [H3L4][H2L4](PF6)3 features a dimeric face-to-face arrangement of two molecules due to the involvement of both the pyrazole-NH and the imidazolium C2H in hydrogen bonding. [H3L1]X2 - [H3L4]X2 serve as precursors for silver(I) complexes with compartmental pyrazolate-bridged bis(NHC) ligands. The complexes have been readily prepared by the Ag2O route and feature either the known [(L1−4)2Ag4]2+ or the new [(H2L1)4Ag4]8+ motif, depending on the solvent for the reaction (MeCN or acetone). [(H2L1)4Ag4](PF6)8 contains a central (pzAg)4 ring with pendant imidazolium side arms. Upon further reaction with Ag2O in MeCN it was found to undergo transformation to the corresponding [(L1)2Ag4](PF6)2. All complexes have been thoroughly studied by NMR spectroscopy in solution, and preliminary luminescence data of [(H2L1)4Ag4](PF6)8 have been recorded

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Structural Variations in Manganese Halide Chain Compounds Mediated by Methylimidazolium Isomers

Crystals ◽

10.3390/cryst10100930 ◽

2020 ◽

Vol 10 (10) ◽

pp. 930

Author(s):

Ceng Han ◽

David B. Cordes ◽

Alexandra M. Z. Slawin ◽

Philip Lightfoot

Keyword(s):

Hydrogen Bonding ◽

Ambient Temperature ◽

X Ray Diffraction ◽

Structural Variations ◽

One Dimensional ◽

X Ray ◽

Chain Compounds ◽

Red Luminescence ◽

New Compounds ◽

Related Compounds

The structures of two new hybrid organic–inorganic manganese halide compounds [1MiH]MnCl3(H2O) and [4MiH]MnCl3(H2O) ([1MiH] = 1-methylimidazolium, [4MiH] = 4-methylimidazolium) have been determined by single crystal X-ray diffraction. Both are composed of one dimensional [MnCl3(H2O)]n− edge-sharing octahedral chains. The structures are compared to the previously reported isomeric analogue [2MiH]MnCl3(H2O) ([2MiH] = 2-methylimidazolium), and three closely related compounds. The variations in packing of the inorganic chains are shown to be influenced by hydrogen bonding abilities of the imidazolium or related moieties. Both new compounds show intense red luminescence at ambient temperature under UV irradiation.

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Effects of structural variations on the hydrogen bond pairing between adenine derivatives and thymine

Macedonian Journal of Chemistry and Chemical Engineering ◽

10.20450/mjcce.2015.644 ◽

2015 ◽

Vol 34 (1) ◽

pp. 159 ◽

Cited By ~ 4

Author(s):

Valya Nikolova ◽

Boris Galabov

Keyword(s):

Hydrogen Bonding ◽

Density Functional ◽

Atomic Charges ◽

Interaction Energies ◽

Excellent Correlation ◽

Structural Variations ◽

Functional Theory ◽

Polar Substituents ◽

Substituted Adenines ◽

Adenine Derivatives

Abstract: The hydrogen bonding between substituted adenines and thymine was investigated by density functional theory computations at the B3LYP/6-311+G(2d,2p) level. The effect of 20 different polar substituents at position 8 in adenine was examined in detail. Three different theoretical parameters, reflecting the electrostatics at the atoms involved in hydrogen bonding, were applied. An excellent correlation between electrostatic potentials at the bonding atoms in the monomer adenines and interaction energies was derived (Eqn. 2). It can be employed in designing bioactive adenine derivatives that are able to bind with a finely adjusted strength to thymine bioreceptor sites. NBO and Hirshfeld atomic charges are found to be less successful as reactivity predictors in these interactions.

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Carbon-13 nmr shifts and C—H coupling constants of deoxybenzoins and related acetophenones

Canadian Journal of Chemistry ◽

10.1139/v81-329 ◽

1981 ◽

Vol 59 (15) ◽

pp. 2266-2282 ◽

Cited By ~ 11

Author(s):

Hem Chandra Jha ◽

Fritz Zilliken ◽

Werner Offermann ◽

Eberhard Breitmaier

Keyword(s):

Hydrogen Bonding ◽

Chemical Shifts ◽

Carbonyl Oxygen ◽

Coupling Constants ◽

Structural Variations ◽

Naturally Occurring ◽

Internal Hydrogen ◽

Benzene Rings ◽

Substitutional Saturation

13C Chemical shifts and resolved carbon–proton couplings of 39 deoxybenzoins and 11 acetophenones, most of which have naturally occurring substitution patterns, are assigned. Individual benzene rings turned out to have typical parameters not affected by structural variations in the rest of the molecule. Due to substitutional saturation, however, these benzenoid carbon shifts markedly deviate from increment additivity. A few trends of these deviations are described. Phenolic hydrogens, fixed between hydroxyl and carbonyl oxygen due to internal hydrogen bonding, are shown to give rise to additional carbon-splittings.

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Exploring structural variations of hydrogen-bonding patterns in cellulose during mechanical pulp refining of tobacco stems

Carbohydrate Polymers ◽

10.1016/j.carbpol.2018.10.024 ◽

2019 ◽

Vol 204 ◽

pp. 247-254 ◽

Cited By ~ 10

Author(s):

Deqing Zhao ◽

Yong Deng ◽

Donglin Han ◽

Lanlan Tan ◽

Yu Ding ◽

...

Keyword(s):

Hydrogen Bonding ◽

Structural Variations ◽

Mechanical Pulp ◽

Bonding Patterns

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Focal Point Evaluation of Energies for Tautomers and Isomers for 3-Hydroxy-2-Butenamide: Evaluation of Competing Internal Hydrogen Bonds of Types -OH…O=, -OH…N, -NH…O=, and CH…X (X=O and N)

Molecules ◽

10.3390/molecules26092623 ◽

2021 ◽

Vol 26 (9) ◽

pp. 2623

Author(s):

Zikri Altun ◽

Erdi Bleda ◽

Carl Trindle

Keyword(s):

Hydrogen Bonding ◽

Hydrogen Bonds ◽

Focal Point ◽

Noncovalent Interactions ◽

Carbonyl Oxygen ◽

Relative Strength ◽

Basis Sets ◽

Structural Variations ◽

Internal Hydrogen ◽

Correlation Consistent

The title compound is a small molecule with many structural variations; it can illustrate a variety of internal hydrogen bonds, among other noncovalent interactions. Here we examine structures displaying hydrogen bonding between carbonyl oxygen and hydroxyl H; between carbonyl oxygen and amino H; hydroxyl H and amino N; hydroxyl O and amino H. We also consider H-bonding in its tautomer 2-oxopropanamide. By extrapolation algorithms applied to Hartree-Fock and correlation energies as estimated in HF, MP2, and CCSD calculations using the cc-pVNZ correlation-consistent basis sets (N = 2, 3, and 4) we obtain reliable relative energies of the isomeric forms. Assuming that such energy differences may be attributed to the presence of the various types of hydrogen bonding, we attempt to infer relative strengths of types of H-bonding. The Atoms in Molecules theory of Bader and the Local Vibrational Modes analysis of Cremer and Kraka are applied to this task. Hydrogen bonds are ranked by relative strength as measured by local stretching force constants, with the stronger =O…HO- > NH…O= > -OH…N well separated from a cluster > NH…O= ≈ >NH…OH ≈ CH…O= of comparable and intermediate strength. Weaker but still significant interactions are of type CH…N which is stronger than CH…OH.

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Crystalloid Inclusions in Hepatocyte Mitochondria and Their Similarity to Cytoplasmic Crystalloids

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100051001 ◽

1974 ◽

Vol 32 ◽

pp. 198-199

Author(s):

Odell T. Minick ◽

Hidejiro Yokoo

Keyword(s):

Liver Disease ◽

Alcoholic Liver Disease ◽

Special Interest ◽

Structural Variations ◽

Mitochondrial Alterations ◽

The Matrix ◽

Crystalloid Inclusions ◽

Liver Biopsies

Mitochondrial alterations were studied in 25 liver biopsies from patients with alcoholic liver disease. Of special interest were the morphologic resemblance of certain fine structural variations in mitochondria and crystalloid inclusions. Four types of alterations within mitochondria were found that seemed to relate to cytoplasmic crystalloids.Type 1 alteration consisted of localized groups of cristae, usually oriented in the long direction of the organelle (Fig. 1A). In this plane they appeared serrated at the periphery with blind endings in the matrix. Other sections revealed a system of equally-spaced diagonal lines lengthwise in the mitochondrion with cristae protruding from both ends (Fig. 1B). Profiles of this inclusion were not unlike tangential cuts of a crystalloid structure frequently seen in enlarged mitochondria described below.

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