scholarly journals Entropy driven chain effects on ligation chemistry

2015 ◽  
Vol 6 (2) ◽  
pp. 1061-1074 ◽  
Author(s):  
Kai Pahnke ◽  
Josef Brandt ◽  
Ganna Gryn'ova ◽  
Peter Lindner ◽  
Ralf Schweins ◽  
...  
Keyword(s):  
Building Block ◽  
Chain Structure ◽  
Step Change ◽  
Side Chain ◽  
On Demand ◽  
Bonding Systems ◽  
Intrinsic Stiffness

Entropic chain effects on dynamic bonding reactions are shown to enable the tuning of reaction equilibria not only by changing the mass of the reactants, but also by merely altering the building block side chain structure and thus the intrinsic stiffness. The findings enable a step change for the design of on-demand bonding systems and reversible ligation chemistry in general.

scholarly journals Relationship of 25-hydroxyvitamin D3 side chain structure to biological activity.

1975 ◽  
Vol 250 (1) ◽  
pp. 226-230
Author(s):  
M F Holick ◽  
M Garabedian ◽  
H K Schnoes ◽  
H F DeLuca
Keyword(s):  
Biological Activity ◽  
Chain Structure ◽  
Side Chain ◽  
Relationship Of

3-(4-Bromophenyl)-5-(4-hydroxyphenyl)isoxazole: a versatile, new molecular building block for side-chain liquid crystal oligomers and polymers

2015 ◽  
Vol 73 (4) ◽  
pp. 959-973 ◽  
Author(s):  
Guilherme D. Vilela ◽  
Thaís H. M. Fernandes ◽  
Rafaela Raupp da Rosa ◽  
Stephen M. Kelly ◽  
Stuart P. Kitney ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Building Block ◽  
Side Chain ◽  
Molecular Building Block

Hemiphasmidic Side-Chain Liquid Crystalline Polymer: From Smectic C Phase to Columnar Phase with a Bundle of Chains as Its Building Block

2012 ◽  
Vol 1 (5) ◽  
pp. 641-645 ◽  
Author(s):  
Jun-Feng Zheng ◽  
Xin Liu ◽  
Xiao-Fang Chen ◽  
Xiang-Kui Ren ◽  
Shuang Yang ◽  
...  
Keyword(s):  
Building Block ◽  
Liquid Crystalline Polymer ◽  
Liquid Crystalline ◽  
Crystalline Polymer ◽  
Side Chain ◽  
Columnar Phase ◽  
Smectic C

scholarly journals Crystal engineered acid-base complexes with 2d and 3d hydrogen bonding systems using p-hydroxybenzoic acid as the building block

2010 ◽  
Vol 75 (4) ◽  
pp. 459-473 ◽  
Author(s):  
Pu Zhao ◽  
Xian Wang ◽  
Fang Jian ◽  
Jun Zhang ◽  
Lian Xiao
Keyword(s):  
Self Assembly ◽  
Building Block ◽  
Three Dimensional ◽  
Hydroxybenzoic Acid ◽  
Acid Base ◽  
3D Network ◽  
Acid And Base ◽  
Butyl Amine ◽  
Bonding Systems ◽  
Simply Connected

p-Hydroxybenzoic acid (p-HOBA) was selected as the building block for self-assembly with five bases, i.e., diethylamine, tert-butyl amine, cyclohexylamine, imidazole and piperazine, and generate the corresponding acid-base complexes 1-5. Crystal structure analyses suggest that proton-transfer from the carboxyl hydrogen to the nitrogen atom of the bases can be observed in 1-4; while only in 5 does a solvent water molecule co-exists with p-HOBA and piperazine. With the presence of O-H?O hydrogen bonds in 1-4, the deprotonated p-hydroxybenzoate anions (p-HOBAA-) are simply connected each other in a head-to-tail motif to form one-dimensional (1D) arrays, which are further extended to distinct two-dimensional (2D) (for 1 and 4) and three-dimensional (3D) (for 2 and 3 ) networks via N-H?O interactions. While in 5, neutral acid and base are combined pair wise by O-H?N and N-H?O bonds to form a 1D tape and then the 1D tapes are sequentially combined by water molecules to create a 3D network. Some interlayer or intralayer C-H?O, C-H?? and ??? interactions help to stabilize the supramolecular buildings. Melting point determination analyses indicate that the five acidbase complexes are not the ordinary superposition of the reactants and they are more stable than the original reactants.

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