The molecular structures of two salicylaldehyde thiosemicarbazone derivatives, namely salicylaldehyde 4-phenylthiosemicarbazone, C(14)H(13)N(3)OS, (I), and 4-methoxysalicylaldehyde 4-phenylthiosemicarbazone, C(15)H(15)N(3)O(2)S, (II), both of potential pharmacological interest, are found in the keto (thione) tautomeric form. The first compound represents a second triclinic polymorph of composition beta-C(14)H(13)N(3)OS. Although both polymorphs crystallize in the same space group (P1), the alpha-polymorph [Seena, Kurup & Suresh (2008). J. Chem. Crystallogr. 38, 93-96] differs from the beta form in its unit-cell volume at 293 K. The molecules in the crystal structures of (I) and (II) are linked into centrosymmetric R(2)(2)(8) dimers by hydrogen bonds of the N-H...S=C type. These dimers are connected through pi-pi stacking and T-shaped C-H...pi interactions into three-dimensional networks.
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http://dx.doi.org/10.1107/S0108270108029016 | DOI Listing |
Acta Crystallogr E Crystallogr Commun
May 2024
Department of Chemistry, Nelson Mandela University, Port Elizabeth, South Africa.
The chemical reaction of 4-bromo-benzoyl-chloride and 2-amino-thia-zole in the presence of potassium thio-cyanate yielded a white solid formulated as CHBrNOS, which consists of 4-bromo-benzamido and 2-benzo-thia-zolyl moieties connected by a thio-urea group. The 4-bromo-benzamido and 2-benzo-thia-zolyl moieties are in a conformtion (sometimes also called -trans due to the single bond) with respect to the N-C bond. The dihedral angle between the mean planes of the 4-bromo-phenyl and the 2-benzo-thia-zolyl units is 10.
View Article and Find Full Text PDFRSC Adv
November 2023
Biomolecular Crystallography Laboratory and DBT-Bioinformatics Center, School of Chemical and Biotechnology, SASTRA Deemed University Thanjavur 613 401 India
Two 1,3,4-oxadiazole-2-thione--Mannich derivatives, specifically 5-(4-chlorophenyl)-3-[(2-trifluoromethylphenylamino)methyl]-1,3,4-oxadiazole-2(3)-thione (1) and 5-(4-chlorophenyl)-3-[(2,5-difluorophenylamino)methyl]-1,3,4-oxadiazole-2(3)-thione (2), were synthesized and then characterized by elemental analysis and NMR (H and C) spectroscopy and the single crystal X-ray diffraction method. The formed weak intermolecular interactions in the solid-state structures of these derivatives were thoroughly investigated utilizing a variety of theoretical tools such as Hirshfeld surface analysis and quantum theory of atoms in molecules (QTAIM). Furthermore, the CLP-PIXEL and density functional theory calculations were used to study the energetics of molecular dimers.
View Article and Find Full Text PDFChem Sci
August 2020
Institut de Chimie Moléculaire et des Matériaux d'Orsay (ICMMO), CNRS, Université Paris-Saclay 91405 Orsay France
In addition to the classical N-H⋯O[double bond, length as m-dash]C non-covalent interaction, less conventional types of hydrogen bonding, such as N-H⋯S, may play a key role in determining the molecular structure. In this work, using theoretical calculations in combination with spectroscopic analysis in both gas phase and solution phase, we demonstrate that both these H-bonding modes exist simultaneously in low-energy conformers of capped derivatives of Attc, a thietane α-amino acid. 6-Membered ring inter-residue N-H⋯S interactions (C6), assisted by hyperconjugation between the thietane ring and the backbone, combine with 5-membered ring intra-residue backbone N-H⋯O[double bond, length as m-dash]C interactions (C5) to provide a C5-C6 feature that stabilizes a planar geometry in the monomer unit.
View Article and Find Full Text PDFPhys Chem Chem Phys
November 2020
Key Laboratory of Micro Nano Optoelectronic Devices and Intelligent Perception Systems, Key Laboratory of Extraordinary Bond Engineering and Advanced Materials Technology of Chongqing, School of Electronic Information Engineering, Yangtze Normal University, Chongqing 408100, China.
The construction of a heterostructure (HS) is an effective strategy to modulate the desired properties of two-dimensional (2D) materials and to extend their applications. In this paper, based on the density functional theory, we predict a metal-free type-II HS formed by h-BN and CN single layers. The h-BN/CN HS possesses a smaller bandgap than individual h-BN and CN single layers, and it exhibits excellent visible light absorption.
View Article and Find Full Text PDFActa Crystallogr E Crystallogr Commun
March 2020
School of Chemistry, University of St Andrews, St Andrews, Fife KY16 9ST, UK.
Chalcones of type 4-CHC(O)CH=CHCH(OCHCCH)-4, where = Cl, Br or MeO, have been converted to the corresponding 4,5-di-hydro-pyrazole-1-carbo-thio-amides using a cyclo-condensation reaction with thio-semicarbazide. The chalcones 1-(4-chloro-phen-yl)-3-[4-(prop-2-yn-yloxy)phen-yl]prop-2-en-1-one, CHClO, (I), and 1-(4-bromo-phen-yl)-3-[4-(prop-2-yn-yloxy)phen-yl]prop-2-en-1-one, CHBrO, (II), are isomorphous, and their mol-ecules are linked into sheets by two independent C-H⋯π(arene) inter-actions, both involving the same aryl ring with one C-H donor approaching each face. In each of the products ()-3-(4-chloro-phen-yl)-5-[4-(prop-2-yn-yloxy)phen-yl]-4,5-di-hydro-pyrazole-1-carbo-thio-amide, CHClNOS, (IV), ()-3-(4-bromo-phen-yl)-5-[4-(prop-2-yn-yloxy)phen-yl]-4,5-di-hydro-pyrazole-1-carbo-thio-amide, CHBrNOS, (V), and ()-3-(4-meth-oxy-phen-yl)-5-[4-(prop-2-yn-yloxy)phen-yl]-4,5-di-hydro-pyrazole-1-carbo-thio-amide, CHNOS, (VI), the reduced pyrazole ring adopts an envelope conformation with the C atom bearing the 4-prop-2-yn-yloxy)phenyl substituent, which occupies the axial site, displaced from the plane of the four ring atoms.
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