Hydrogen bonds in N-(3-chloro-2-benzo[b]thienocarbonyl)- and N-(2-benzo[b]thienocarbonyl)-N'-monosubstituted thioureas

1987 ◽  
Vol 52 (11) ◽  
pp. 2673-2679 ◽  
Author(s):  
Oľga Hritzová ◽  
Peter Kutschy ◽  
Ján Imrich ◽  
Thomas Schöffmann

N-(3-Chloro-2-benzo[b]thienocarbonyl)-N'-monosubstituted thiourea derivatives undergo photocyclizations with lower yields than those obtained from analogous N',N'-disubstituted derivatives. This decreased reactivity is caused by the existence of a six-membered cyclic form with the very strong hydrogen bond NH···O=C. The possibility of formation of various conformers has been found with N-(2-benzo[b]thienocarbonyl)-N'-monosubstituted thiourea derivatives as a consequence of the rotation around the C(2)-C(O) connecting line.

2021 ◽  
pp. 1-9
Author(s):  
James A. Kaduk ◽  
Nicholas C. Boaz ◽  
Emma L. Markun ◽  
Amy M. Gindhart ◽  
Thomas N. Blanton

The crystal structure of osimertinib mesylate Form B has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional techniques. Osimertinib mesylate Form B crystallizes in space group P-1 (#2) with a = 11.42912(17), b = 11.72274(24), c = 13.32213(22) Å, α = 69.0265(5), β = 74.5914(4), γ = 66.4007(4)°, V = 1511.557(12) Å3, and Z = 2. The crystal structure is characterized by alternating layers of cation–anion and parallel stacking interactions parallel to the ab-planes. The cation is protonated at the nitrogen atom of the dimethylamino group, which forms a strong hydrogen bond between the cation and the anion. That hydrogen atom also participates in a weaker intramolecular hydrogen bond to an amino nitrogen. There are two additional N–H⋅⋅⋅O hydrogen bonds between the cation and the anion. Several C–H⋅⋅⋅O hydrogen bonds also link the cations and anions. The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™.


2016 ◽  
Vol 31 (2) ◽  
pp. 97-103 ◽  
Author(s):  
James A. Kaduk ◽  
Kai Zhong ◽  
Amy M. Gindhart ◽  
Thomas N. Blanton

The crystal structure of rivastigmine hydrogen tartrate has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional techniques. Rivastigmine hydrogen tartrate crystallizes in space group P21 (#4) with a = 17.538 34(5), b = 8.326 89(2), c = 7.261 11(2) Å, β = 98.7999(2)°, V = 1047.929(4) Å3, and Z = 2. The un-ionized end of the hydrogen tartrate anions forms a very strong hydrogen bond with the ionized end of another anion to form a chain. The ammonium group of the rivastigmine cation forms a strong discrete hydrogen bond with the carbonyl oxygen atom of the un-ionized end of the tartrate anion. These hydrogen bonds form a corrugated network in the bc-plane. Both hydroxyl groups of the tartrate anion form intramolecular O–H⋯O hydrogen bonds. Several C–H⋯O hydrogen bonds appear to contribute to the crystal energy. The powder pattern is included in the Powder Diffraction File™ as entry 00-064-1501.


2021 ◽  
Author(s):  
Verónica Jornet-Mollá ◽  
Carlos Giménez-Saiz ◽  
Laura Cañadillas-Delgado ◽  
Dmitry S. Yufit ◽  
Judith A. K. Howard ◽  
...  

A proton migration across a short strong hydrogen bond can be triggered by spin crossover of a remote Fe2+ cation, with the onset of a photoinduced activation energy barrier for proton motion at low temperatures.


2018 ◽  
Vol 33 (4) ◽  
pp. 319-326
Author(s):  
Austin M. Wheatley ◽  
James A. Kaduk ◽  
Amy M. Gindhart ◽  
Thomas N. Blanton

The crystal structure of vardenafil hydrochloride trihydrate has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional techniques. Vardenafil hydrochloride trihydrate crystallizes in space group C2/c (#15) with a = 34.78347(16), b = 11.56752(4), c = 14.69308(5) Å, β = 93.3410(4), V = 5901.839(30) Å3, and Z = 8. The fused ring system and the phenyl ring are nearly co-planar; the interplanar angle between them is 6.0°. Two intramolecular hydrogen bonds help determine this conformation. These planes stack along the c-axis. The side chains of these ring systems have a large Uiso and are neighbors in the stacks. Along the a-axis, these stacks are separated by hydrophilic layers of chloride, water molecules, and the positively charged nitrogen atoms of the vardenafil cation. Hydrogen bonds are prominent in the crystal structure. The protonated nitrogen atom forms a strong hydrogen bond to the chloride anion. The water molecules form a hexagon, making hydrogen bonds with themselves, as well as the C1 and a ring nitrogen atom. These discrete hydrogen bonds form a cluster, and there is no extended hydrogen bond network. There are many C–H⋯Cl, C–H⋯O, and C–H⋯N hydrogen bonds, which (although individually weak) contribute significantly to the crystal energy. The powder pattern is included in the Powder Diffraction File™ as entry 00-066-1620.


1997 ◽  
Vol 75 (8) ◽  
pp. 1099-1105 ◽  
Author(s):  
Ian M. Walker ◽  
Paul J. McCarthy

The fundamental and overtone vibrational spectra of Ba(NO2)2•X2O (X=H,D) have been interpreted using the local mode model. The calculated parameters are consistent with the structure, which has one strong hydrogen bond and one weak bifurcated hydrogen bond. Evidence for Fermi resonance between stretch and bend features having similar energies is discussed. Evidence for the breakdown of the simple Morse oscillator model, which was quite successful for [Formula: see text] hydrogen bonds, is also presented. Keywords: overtone, spectra, near-infrared, hydrates, local-mode model.


2008 ◽  
Vol 64 (4) ◽  
pp. 491-496 ◽  
Author(s):  
Peter A. Wood ◽  
Elna Pidcock ◽  
Frank H. Allen

The occurrence, geometries and energies of hydrogen bonds from N—H and O—H donors to the S acceptors of thiourea derivatives, thioamides and thiones are compared with data for their O analogues – ureas, amides and ketones. Geometrical data derived from the Cambridge Structural Database indicate that hydrogen bonds to the C=S acceptors are much weaker than those to their C=O counterparts: van der Waals normalized hydrogen bonds to O are shorter than those to S by ∼ 0.25 Å. Further, the directionality of the approach of the hydrogen bond with respect to S, defined by the C=S...H angle, is in the range 102–109°, much lower than the analogous C=O...H angle which lies in the range 127–140°. Ab initio calculations using intermolecular perturbation theory show good agreement with the experimental results: the differences in hydrogen-bond directionality are closely reproduced, and the interaction energies of hydrogen bonds to S are consistently weaker than those to O, by ∼ 12 kJ mol−1, for each of the three compound classes. There are no CSD examples of hydrogen bonds to aliphatic thiones, (Csp 3)2C=S, consistent with the near-equality of the electronegativities of C and S. Thioureas and thioamides have electron-rich N substituents replacing the Csp 3 atoms. Electron delocalization involving C=S and the N lone pairs then induces a significant >Cδ+=Sδ− dipole, which enables the formation of the medium-strength C=S...H bonds observed in thioureas and thioamides.


2001 ◽  
Vol 56 (10) ◽  
pp. 1041-1051 ◽  
Author(s):  
Oliver Moers ◽  
Ilona Lange ◽  
Karna Wijaya ◽  
Armand Blaschette ◽  
Peter G. Jones

In order to study packing arrangements and hydrogen bonding networks, low-temperature X-ray structures were determined for pyH+(MeSO2)2N- (M, orthorhombic, space group P212121, Z′ = 1) and 4,4′-bipyH22+ ·(MeSO2)2N- (D, monoclinic, C2/c, Z′ = 0.5). The structures consist of ionic formula entities assembled by N+-H···N- hydrogen bonds; the dication in D displays crystallographic C2 symmetry and has its two pyridyl moieties twisted by 43.9°. According to the packing architectures, D represents a supramolecular dimer of the monomeric congener M. In particular, the (MeSO2)2N- ions of the M structure are associated via short C(sp3) - H···O contacts to form a diamondoid network, whereas in D a topologically congruent framework is constructed from weakly hydrogen-bonded [(MeSO2)N-]2 nodes. Hexagonal channels in the anion substructures each include two adjacent stacks of monomeric pyH+ or “dimeric” 4,4-bipyH22+ cations that are linked to the channel walls by the strong hydrogen bond(s) and a set of short Car-H···O contacts. All C - H···O taken into consideration have normalized parameters d(H···O) ≤ 270 pm and θ(C - H···O) ≥ 115°.


Homeopathy ◽  
2019 ◽  
Vol 108 (02) ◽  
pp. 121-127 ◽  
Author(s):  
Tara Bhattacharya ◽  
Payaswini Maitra ◽  
Debbethi Bera ◽  
Kaushik Das ◽  
Poonam Bandyopadhyay ◽  
...  

Background For the study of homeopathic medicines in proper perspective, emerging techniques in material science are being used. Vibrational spectroscopy is one such tool for providing information on different states of hydrogen bonding as an effect of potentization. The associated change in electrical properties is also correlated with this effect. Objective From the vibrational spectra, the changes in hydrogen bonding due to dilution followed by unidirectional vigorous shaking (together termed potentization) of 91% ethanol and two homeopathic medicines Chininum purum and Acidum benzoicum have been studied. The aim was to correlate the result with the change in the electrical properties of the system. Methods Raman spectroscopy was used to study the vibrational spectra. A U-shaped glass tube (electrochemical cell), where one arm contained bi-distilled water and the other arm alcohol/homeopathic medicine (the arms being separated by a platinum foil), was used to measure the voltage generated across two symmetrically placed platinum electrodes. Results For all samples, it was observed that potentization affected the intensity of OH stretching bands at the frequencies 3240 cm−1, 3420 cm−1 and 3620 cm−1, corresponding to strong hydrogen bond, weak hydrogen bond and broken hydrogen bond, respectively. With the increase in potency, in the presence and absence of the two medicines in ethanol, the number of OH groups linked by strong hydrogen bonds decreased, while the number of OH groups with weak hydrogen bonds increased. With the increase in potentization, the number of OH groups with broken hydrogen bonds showed a difference in the presence and absence of the medicine.The voltage measurements for ethanol show that, with succussion, the magnitude of voltage increased with the two medicines at lower potencies, but not at higher potency where the voltage is lower. Acidum benzoicum, which is acidic in nature, had higher voltage values (113mV, 130 mV and 118 mV at 6C, 30C and 200C, respectively), compared with Chininum purum, which is basic in nature (20 mV, 85 mV and 65 mV at 6C, 30C and 200C, respectively). Conclusion The experimental results indicate a correlation between the vibrational and electrical properties of the homeopathic medicines Acidum benzoicum and Chininum purum at different potencies.


2018 ◽  
Vol 34 (1) ◽  
pp. 66-73
Author(s):  
Jordan A. Krueger ◽  
James A. Kaduk ◽  
Amy M. Gindhart ◽  
Thomas N. Blanton

The crystal structure of hydroxyzine dihydrochloride has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional techniques. Hydroxyzine dihydrochloride crystallizes in space group P21 (#4) with a = 11.48735(10), b = 7.41792(7), c = 14.99234(15) Å, β = 110.4383(10)°, V = 1197.107(13) Å3, and Z = 2. The hydroxyl-containing side chain of the cation is disordered over two conformations, with ~70/30% occupancy. The crystal structure consists of alternating polar (which includes the cation-anion interactions and hydrogen bonds) and nonpolar layers parallel to the ab-plane. The crystal structure is dominated by hydrogen bonds. Each of the protonated nitrogen atoms forms a very strong hydrogen bond to one of the chloride anions. The hydroxyl group forms a strong hydrogen bond to one of the chloride anions in both conformations, and there are subtle differences in the hydrogen bonding patterns between the conformations. The powder pattern is included in the Powder Diffraction File™ as entry 00-066-1603.


RSC Advances ◽  
2019 ◽  
Vol 9 (56) ◽  
pp. 32759-32770 ◽  
Author(s):  
Arun Kumar Patel ◽  
Sandeep Kumar Mishra ◽  
Kiran Krishnamurthy ◽  
N. Suryaprakash

NMR studies reveal very strong hydrogen bond unbreakable even in high polarity solvents.


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