Hydrogen-bonded supramolecular polymers from derivatives of α-amino-ε-caprolactam: A bio-based material

2011 ◽  
Vol 49 (11) ◽  
pp. 2451-2460 ◽  
Author(s):  
Eylem Tarkin-Tas ◽  
Christopher A. Lange ◽  
Lon J. Mathias
2018 ◽  
Vol 54 (8) ◽  
pp. 892-895 ◽  
Author(s):  
E. W. Dahl ◽  
H. T. Dong ◽  
N. K. Szymczak

A series of copper complexes bearing new 6-substituted tris(2-pyridylmethyl)amine ligands (LR) appended with NH(p-R-C6H4) groups (R = H, CF3, OMe) were prepared.


2002 ◽  
Vol 99 (8) ◽  
pp. 4977-4982 ◽  
Author(s):  
L. Brunsveld ◽  
J. A. J. M. Vekemans ◽  
J. H. K. K. Hirschberg ◽  
R. P. Sijbesma ◽  
E. W. Meijer

Author(s):  
Thomas Gelbrich ◽  
Denise Rossi ◽  
Ulrich J. Griesser

Polymorph (Ia) of eldoral [5-ethyl-5-(piperidin-1-yl)barbituric acid or 5-ethyl-5-(piperidin-1-yl)-1,3-diazinane-2,4,6-trione], C11H17N3O3, displays a hydrogen-bonded layer structure parallel to (100). The piperidine N atom and the barbiturate carbonyl group in the 2-position are utilized in N—H...N and N—H...O=C hydrogen bonds, respectively. The structure of polymorph (Ib) contains pseudosymmetry elements. The two independent molecules of (Ib) are connectedviaN—H...O=C(4/6-position) and N—H...N(piperidine) hydrogen bonds to give a chain structure in the [100] direction. The hydrogen-bonded layers, parallel to (010), formed in the salt diethylammonium 5-ethyl-5-(piperidin-1-yl)barbiturate [or diethylammonium 5-ethyl-2,4,6-trioxo-5-(piperidin-1-yl)-1,3-diazinan-1-ide], C4H12N+·C11H16N3O3−, (II), closely resemble the corresponding hydrogen-bonded structure in polymorph (Ia). Like many other 5,5-disubstituted derivatives of barbituric acid, polymorphs (Ia) and (Ib) contain theR22(8) N—H...O=C hydrogen-bond motif. However, the overall hydrogen-bonded chain and layer structures of (Ia) and (Ib) are unique because of the involvement of the hydrogen-bond acceptor function in the piperidine group.


2012 ◽  
Vol 50 (18) ◽  
pp. 3775-3787 ◽  
Author(s):  
Mirela-Fernanda Zaltariov ◽  
Maria Cazacu ◽  
Sergiu Shova ◽  
Angelica Vlad ◽  
Iuliana Stoica ◽  
...  

2011 ◽  
Vol 47 (38) ◽  
pp. 10755 ◽  
Author(s):  
Shao-Lu Li ◽  
Tangxin Xiao ◽  
Bingjie Hu ◽  
Yajie Zhang ◽  
Feng Zhao ◽  
...  

1992 ◽  
Vol 70 (1) ◽  
pp. 254-271 ◽  
Author(s):  
Ulrike Spohr ◽  
Eugenia Paszkiewicz-Hnatiw ◽  
Naohiko Morishima ◽  
Raymond U. Lemieux

The relative potencies of a wide variety of deoxygenated derivatives of the methyl glycoside of α-L-Fuc-(1 → 2)-β-D-Gal-(1 → 4)- β-D-GlcNAc (the H-type 2 human blood group related trisaccharide) for the inhibition of the binding of an artificial H-type 2 antigen by the lectin I of Ulexeuropaeus confirmed the previous evidence that the key and productive interaction involves only the three hydroxyl groups of the α-L-fucose unit, the hydroxyl at the 3-position of the β-D-galactose residue, and the nonpolar groups in their immediate environment. Except for the acetamido group and the hydroxymethyl of the β-D-Gal unit, which stay in the aqueous phase, on complex formation the remaining three hydroxyl groups appear to come to reside at or near the periphery of the combining site since their replacement by hydrogen causes relatively small changes (< ± 1 kcal/mol) in the stability of the complex (ΔG0). Relatively much larger but compensating changes occur for the enthalpy and entropy terms, and these may arise primarily from the differences in the water structure about the periphery of the combining site and the oligosaccharide both prior to and after complexation. It is proposed that steric constraints lead to an ordered state of the water molecules hydrogen-bonded to the polar groups within the cleft formed by the key region of the amphiphilic combining site. Their release to form less ordered clusters of more strongly hydrogen-bonded water molecules in bulk solution would contribute importantly to the driving force for complexation. It is demonstrated that the surface used for the binding of H-type 2-OMe by a monoclonal anti-H antibody is virtually identical to that used by the Ulex lectin. Keywords: molecular recognition, H-type 2 blood group determinant and deoxygenated derivatives, lectin I of Ulexeuropaeus, anti-H-type 2 monoclonal antibody, enthalpy–entropy compensation.


2014 ◽  
Vol 20 (51) ◽  
pp. 16980-16986 ◽  
Author(s):  
Yi-Fei Han ◽  
Wen-Qiang Chen ◽  
Hong-Bo Wang ◽  
Ying-Xue Yuan ◽  
Na-Na Wu ◽  
...  

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