scholarly journals Hydrogen bonds in supramolecular crystals of carboxylic acid salts with aliphatic amines

2015 ◽  
Vol 71 (a1) ◽  
pp. s308-s308
Author(s):  
Paulina Sołtysiak ◽  
Bła&zej Dziuk ◽  
Bartosz Zarychta ◽  
Krzysztof Ejsmont
2021 ◽  
pp. 1-8
Author(s):  
James A. Kaduk ◽  
Amy M. Gindhart ◽  
Thomas N. Blanton

The crystal structure of tofacitinib dihydrogen citrate (tofacitinib citrate) has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional techniques. Tofacitinib dihydrogen citrate crystallizes in space group P212121 (#19) with a = 5.91113(1), b = 12.93131(3), c = 30.43499(7) Å, V = 2326.411(6) Å3, and Z = 4. The crystal structure consists of corrugated layers perpendicular to the c-axis. Within the layers, cation⋯anion and anion⋯anion hydrogen bonds link the fragments into a two-dimensional network parallel to the ab-plane. Between the layers, there are only van der Waals contacts. A terminal carboxylic acid group in the citrate anion forms a strong charge-assisted hydrogen bond to the ionized central carboxylate group. The other carboxylic acid acts as a donor to the carbonyl group of the cation. The citrate hydroxy group forms an intramolecular charge-assisted hydrogen bond to the ionized central carboxylate. Two protonated nitrogen atoms in the cation act as donors to the ionized central carboxylate of the anion. These hydrogen bonds form a ring with the graph set symbol R2,2(8). The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™ (PDF®).


1977 ◽  
Vol 42 (7) ◽  
pp. 1189-1194 ◽  
Author(s):  
A. Paul Krapcho ◽  
David S. Kashdan ◽  
E. G. E. Jahngen ◽  
A. J. Lovey

2009 ◽  
Vol 65 (6) ◽  
pp. o1429-o1429
Author(s):  
Zhen-Dong Zhao ◽  
Yu-Xiang Chen ◽  
Yu-Min Wang ◽  
Liang-Wu Bi

The title compound, also known as isopimaric acid, C20H30O2, was isolated from slash pine rosin. There are two unique molecules in the unit cell. The two cyclohexane rings have classical chair conformations. The cyclohexene ring represents a semi-chair. The molecular conformation is stabilized by weak intramolecular C—H...O hydrogen-bonding interactions. The molecules are dimerized through their carboxyl groups by O—H...O hydrogen bonds, formingR22(8) rings.


2017 ◽  
Vol 73 (8) ◽  
pp. 1264-1267 ◽  
Author(s):  
Okky Dwichandra Putra ◽  
Daiki Umeda ◽  
Kaori Fukuzawa ◽  
Mihoko Gunji ◽  
Etsuo Yonemochi

Epalerstat {systematic name: (5Z)-5-[(2E)-2-methyl-3-phenylprop-2-en-1-ylidene]-4-oxo-2-sulfanylidene-1,3-thiazolidine-3-acetic acid} crystallized as an acetone monosolvate, C15H13NO3S2·C3H6O. In the epalerstat molecule, the methylpropylenediene moiety is inclined to the phenyl ring and the five-membered rhodamine ring by 21.4 (4) and 4.7 (4)°, respectively. In addition, the acetic acid moiety is found to be almost normal to the rhodamine ring, making a dihedral angle of 85.1 (2)°. In the crystal, a pair of O—H...O hydrogen bonds between the carboxylic acid groups of epalerstat molecules form inversion dimers with an R 2 2(8) loop. The dimers are linked by pairs of C—H...O hydrogen bonds, enclosing R 2 2(20) loops, forming chains propagating along the [101] direction. In addition, the acetone molecules are linked to the chain by a C—H...O hydrogen bond. Epalerstat acetone monosolvate was found to be isotypic with epalerstat tertrahydrofuran solvate [Umeda et al. (2017). Acta Cryst. E73, 941–944].


Sign in / Sign up

Export Citation Format

Share Document