Ranitidine hydrochloride (RAN-HCl), a known anti-ulcer drug, is the product of reaction between HCl and ranitidine base (RAN-B). RAN-HCl has been extensively studied; however this is not the case of the RAN-B. The solid state characterization of RAN-B polymorphs has been carried out using different analytical techniques (microscopy, thermal analysis, Fourier transform infrared spectrometry in the attenuated total reflection mode, (13)C-CPMAS-NMR spectroscopy and X-ray powder diffraction). The crystal structures of RAN-B form I and form II have been determined using conventional X-ray powder diffraction in combination with simulated annealing and whole profile pattern matching, and refined using rigid-body Rietveld refinement. RAN-B form I is a monoclinic polymorph with cell parameters: a = 7.317(2), b = 9.021(2), c = 25.098(6) A, beta = 95.690(1) degrees and space group P2(1)/c. The form II is orthorhombic: a = 31.252(4), b = 13.052(2), c = 8.0892(11) A with space group Pbca. In RAN-B polymorphs, the nitro group is involved in a strong intramolecular hydrogen bond responsible for the existence of a Z configuration in the enamine portion of the molecules. A tail to tail packing motif can be denoted via intermolecular hydrogen bonds. The crystal structures of RAN-B forms are compared to those of RAN-HCl polymorphs. RAN-B polymorphs are monotropic polymorphic pairs.
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http://dx.doi.org/10.1002/jps.21395 | DOI Listing |
R Soc Open Sci
January 2025
Department of Industrial Chemistry, College of Natural and Applied Sciences, Addis Ababa Science and Technology University, PO Box 16417, Addis Ababa, Ethiopia.
The asymmetric Schiff base prepared from ethylenediamine and pyridine-2-carboxaldehyde reacts with Fe(ClO)·6HO to form the Fe(II) complex [FeL](ClO) with L = ,-diethyl-'-(pyridin-2-yl)methylene)ethane-1,2-diamine, where the Fe(III) starting material has been unexpectedly reduced to Fe(II). This complex was characterized by elemental analysis, infrared spectra, single crystal and powder X-ray diffraction measurements, variable temperature DC magnetic measurement and room temperature Mössbauer spectroscopy. The asymmetric ligand L coordinates in a tridentate fashion through its pyridyl, azomethine and amino nitrogen atoms, generating a distorted octahedral geometry around the central metal ion.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
January 2025
University of Science and Technology Beijing, School of Chemistry and Biological Engineering, CHINA.
Designing and realizing new topologies represent one of the most important ways toward developing new structures and functionalities for molecule-based frameworks including SOFs, MOFs, and COFs. Herein, Aldol condensation between 5,10,15,20-tetrayl(tetrakis(([1,1':3',1''-terphenyl]-4,4''-dicarbaldehyde)))-porphyrin (TTEP) and 2,4,6-trimethyl-1,3,5-triazine (TMT) affords the vinylene-linked 3D covalent organic framework Por-COF-cya. Powder X-ray diffraction (PXRD) in combination with structural simulation reveals its high crystalline structure with an unprecedented cya topology in the molecule-based frameworks reported thus far.
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January 2025
Department of Pharmaceutics, Faculty of Pharmacy, Assiut University, Assiut, Egypt.
Isoniazid (INH) and rifampicin (RIF) are the two main drugs used for the management of tuberculosis. They are often used as a fixed drug combination, but their delivery is challenged by suboptimal solubility and physical instability. This study explores the potential of active pharmaceutical ingredient-ionic liquids (API-ILs) to improve the physicochemical and pharmaceutical properties of INH and RIF.
View Article and Find Full Text PDFIUCrdata
December 2024
Centre for Materials Science and Nanotechnology, Department of Chemistry, University of Oslo, PO Box 1033, NO-0315 Oslo, Norway.
Tin(IV) sulfate dihydrate, Sn(SO)·2HO, was prepared in a reflux of sulfuric acid under oxidizing conditions. Its crystal structure was determined from powder synchrotron X-ray diffraction data and is constructed of (100) layers of [SnO(HO)] octa-hedra (point group symmetry 1) corner-connected by sulfate tetra-hedra. Hydrogen bonds of moderate strength between the water mol-ecules and sulfate O atoms hold the layers together.
View Article and Find Full Text PDFActa Crystallogr E Crystallogr Commun
January 2025
Institut für Anorganische Chemie, Universität Kiel, Max-Eyth.-Str. 2, 24118 Kiel, Germany.
Reaction of Co(NCS) with 4-methyl-pyridine in water leads to the formation of single crystals of the title compound, [Co(NCS)(CHN)] . The asymmetric unit consists of two crystallographically independent thio-cyanate anions and two crystallographically independent 4-methyl-pyridine coligands in general positions, as well as of two different Co cations, of which one is located on a twofold rotational axis, whereas the second occupies a center of inversion. The methyl H atoms in both 4-methyl-pyridine ligands are disordered and were refined using a split model.
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