Supramolecular architecture of self-adhesive calix[4]arene thiourea derivative by hydrogen bonding and π–π interactions

2004 ◽  
Vol 691 (1-3) ◽  
pp. 25-31 ◽  
Author(s):  
Bang-Tun Zhao ◽  
Yu Liu ◽  
Heng-Yi Zhang
Author(s):  
Natthaya Meundaeng ◽  
Apinpus Rujiwatra ◽  
Timothy J. Prior

The linear two-coordinate silver (I) complex [Ag(C4H2NO2S)(C4H3NO2S)] or [Ag(2-Htza)(2-tza)] is reported (2-Htza = 1,3-thiazole-2-carboxylic acid). The AgI ion is coordinated by two heterocyclic N atoms from two ligands in a linear configuration, forming a discrete coordination complex. There is an O—H...O hydrogen bond between 2-tza− and 2tzaH of adjacent complexes. The hydrogen atom is shared between the two oxygen atoms. This interaction produces a hydrogen-bonded tape parallel to the [110] direction, which is augmented through intermolecular C—H...O hydrogen-bonding interactions between the bound thiazole groups. There is a further rather long Ag...O interaction [2.8401 (13) Å, compared with a mean of 2.54 (11) Å for 23 structures in the CSD] that assembles these tapes into columns, between which there are C—H...π interactions, leading to the formation of a three-dimensional supramolecular architecture.


Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2074
Author(s):  
Sara Tabandeh ◽  
Cristina Elisabeth Lemus ◽  
Lorraine Leon

Electrostatic interactions, and specifically π-interactions play a significant role in the liquid-liquid phase separation of proteins and formation of membraneless organelles/or biological condensates. Sequence patterning of peptides allows creating protein-like structures and controlling the chemistry and interactions of the mimetic molecules. A library of oppositely charged polypeptides was designed and synthesized to investigate the role of π-interactions on phase separation and secondary structures of polyelectrolyte complexes. Phenylalanine was chosen as the π-containing residue and was used together with lysine or glutamic acid in the design of positively or negatively charged sequences. The effect of charge density and also the substitution of fluorine on the phenylalanine ring, known to disrupt π-interactions, were investigated. Characterization analysis using MALDI-TOF mass spectroscopy, H NMR, and circular dichroism (CD) confirmed the molecular structure and chiral pattern of peptide sequences. Despite an alternating sequence of chirality previously shown to promote liquid-liquid phase separation, complexes appeared as solid precipitates, suggesting strong interactions between the sequence pairs. The secondary structures of sequence pairs showed the formation of hydrogen-bonded structures with a β-sheet signal in FTIR spectroscopy. The presence of fluorine decreased hydrogen bonding due to its inhibitory effect on π-interactions. π-interactions resulted in enhanced stability of complexes against salt, and higher critical salt concentrations for complexes with more π-containing amino acids. Furthermore, UV-vis spectroscopy showed that sequences containing π-interactions and increased charge density encapsulated a small charged molecule with π-bonds with high efficiency. These findings highlight the interplay between ionic, hydrophobic, hydrogen bonding, and π-interactions in polyelectrolyte complex formation and enhance our understanding of phase separation phenomena in protein-like structures.


2014 ◽  
Vol 70 (5) ◽  
pp. 517-521
Author(s):  
Yu-Xiu Jin ◽  
Fang Yang ◽  
Li-Min Yuan ◽  
Chao-Guo Yan ◽  
Wen-Long Liu

In poly[[μ3-2,2′-(disulfanediyl)dibenzoato-κ5 O:O,O′:O′′,O′′′](1,10-phenanthroline-κ2 N,N′)cadmium(II)], [Cd(C14H8O4S2)(C12H8N2)] n , the asymmetric unit contains one CdII cation, one 2,2′-(disulfanediyl)dibenzoate anion (denoted dtdb2−) and one 1,10-phenanthroline ligand (denoted phen). Each CdII centre is seven-coordinated by five O atoms of bridging/chelating carboxylate groups from three dtdb2− ligands and by two N atoms from one phen ligand, forming a distorted pentagonal–bipyramidal geometry. The CdII cations are bridged by dtdb2− anions to give a two-dimensional (4,4) layer. The layers are stacked to generate a three-dimensional supramolecular architecture via a combination of aromatic C—H...π and π–π interactions. The thermogravimetric and luminescence properties of this compound were also investigated.


2011 ◽  
Vol 975 (1-3) ◽  
pp. 106-110 ◽  
Author(s):  
Carolina Estarellas ◽  
Antonio Frontera ◽  
David Quiñonero ◽  
Pere M. Deyà

2012 ◽  
Vol 68 (8) ◽  
pp. m203-m205 ◽  
Author(s):  
Mario Tenne ◽  
Yvonne Unger ◽  
Thomas Strassner

The title platinum(II) complex, [Pt(C10H8BrN2)(C5H7O2)], has a bidentate cyclometallated phenylimidazolylidene ligand and an acetylacetonate spectator ligand, which form a distorted square-planar coordination environment around the PtIIcentre. In the solid state, the molecules are oriented in a parallel fashion by intermolecular hydrogen bonding and π–π and C—H...π interactions, while close Pt...Pt contacts are not observed. The structure is only the second example for this new class of compounds.


2015 ◽  
Vol 71 (9) ◽  
pp. o636-o636
Author(s):  
Nadiah Ameram ◽  
Farook Adam

In the title compound, C16H17N3OS, a benzoyl thiourea derivative, the planes of the pyridine and benzene rings are inclined to one another by 66.54 (9)°. There is an intramolecular N—H...O hydrogen bond present forming anS(6) ring motif. In the crystal, molecules are linkedviapairs of N—H...N hydrogen bonds, forming inversion dimers, which are reinforced by pairs of C—H...S hydrogen bonds. The dimers are linkedviaC—H...π interactions, forming ribbons along [010].


2007 ◽  
Vol 119 (46) ◽  
pp. 8938-8940 ◽  
Author(s):  
Mark Mascal ◽  
Ilya Yakovlev ◽  
Edward B. Nikitin ◽  
James C. Fettinger

CrystEngComm ◽  
2016 ◽  
Vol 18 (1) ◽  
pp. 62-67
Author(s):  
Yoona Jang ◽  
Seo Yeon Yoo ◽  
Hye Rin Gu ◽  
Yu Jin Lee ◽  
Young Shin Cha ◽  
...  

6-Chloro-9-propyl-purin-2-amine (pr-GCl) forms two-dimensional hydrogen-bonded networks which in turn stack via π–π interactions, leading to the formation of bilayers that can accommodate organic guest molecules.


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