Polymorphism of 6-methyluracil, which affects the regulation of lipid peroxidation and wound healing, has been studied by experimental and quantum chemical methods. Two known polymorphic modifications and two new crystalline forms were crystallized and characterized by single crystal and powder X-ray diffraction (XRD) methods as well as by the differential scanning calorimetry (DSC) method and infrared (IR) spectroscopy. The calculations of pairwise interaction energies between molecules and lattice energies in periodic boundary conditions have shown that the polymorphic form used in the pharmaceutical industry and two new forms and , which can be formed due to temperature violations, may be considered as metastable.
View Article and Find Full Text PDFTriply Periodic Minimal Surfaces (TPMS) are promising structures for bone tissue engineering scaffolds due to their relatively high mechanical energy absorption, smoothly interconnected porous structure, scalable unit cell topology, and relatively high surface area per volume. Calcium phosphate-based materials, such as hydroxyapatite and tricalcium phosphate, are very popular scaffold biomaterials due to their biocompatibility, bioactivity, compositional similarities to bone mineral, non-immunogenicity, and tunable biodegradation. Their brittle nature can be partially mitigated by 3D printing them in TPMS topologies such as gyroids, which are widely studied for bone regeneration, as evidenced by their presence in popular 3D-printing slicers, modeling systems, and topology optimization tools.
View Article and Find Full Text PDFAnthocyanins in red cabbage, sweet potato, and Tradescantia pallida leaves were characterised. A total of 18 non-, mono-, and diacylated cyanidins was identified in red cabbage by high performance liquid chromatography-diode array detection coupled to high-resolution and multi-stage mass spectrometry. Sweet potato leaves contained 16 different cyanidin- and peonidin glycosides being predominantly mono- and diacylated.
View Article and Find Full Text PDFActa Crystallogr B Struct Sci Cryst Eng Mater
June 2022
A polymorphic transition as a result of grinding was found for 3-[1-(tert-butoxycarbonyl)azetidin-3-yl]-1,2-oxazole-4-carboxylic acid. The thorough study of polymorphic structures before and after crystal structure transformation has revealed some pre-conditions for a polymorphic transition and regularities of changes in molecular and crystal structure. In metastable polymorph 1a, the conformationally flexible molecule adopts a conformation with the higher energy and forms a less preferable linear supramolecular synthon.
View Article and Find Full Text PDFThe hemihydrate of 4-[(benzyl-amino)-carbon-yl]-1-methyl-pyridinium bromide, CHNO·Br·0.5HO, was studied by single-crystal and powder X-ray diffraction methods. In the asymmetric unit, two organic cations of similar conformation, two bromide anions and one water mol-ecule are present.
View Article and Find Full Text PDFActa Crystallogr E Crystallogr Commun
January 2022
Two salts of 4-[(benzyl-amino)-carbon-yl]-1-methyl-pyridinium () with chloride (CHNO·Cl) and bromide (CHNO·Br) anions were studied and compared with the iodide salt. crystallizes in the centrosymmetric space group 2/ while and form crystals in the Sohncke space group 222. Crystals of are isostructural to those of .
View Article and Find Full Text PDFActa Crystallogr B Struct Sci Cryst Eng Mater
February 2022
A study of two polymorphic forms of 1-allyl-4-hydroxy-2,2-dioxo-N-(4-methoxyphenyl)-1-2λ,1-benzothiazine-3-carboxamide (a structural analogue of piroxicam) has revealed some regularities in the crystal structure formation due to different evaporation rates from the tested solvents. The monoclinic polymorph crystallized from ethyl acetate is formed due to a large number of very weak C-H..
View Article and Find Full Text PDFActa Crystallogr E Crystallogr Commun
December 2021
Single crystals of the langbeinite-type phosphates KNaTiFe(PO) and KNaTiFe(PO) were grown by crystallization from high-temperature self-fluxes in the system NaO-KO-PO-TiO-FeO using fixed molar ratios of (Na+K):P = 1.0, Ti:P = 0.20 and Na:K = 1.
View Article and Find Full Text PDFActa Crystallogr E Crystallogr Commun
December 2021
The two iodide salts, 4-[(benzyl-amino)-carbon-yl]-1-methyl-pyridinium iodide-iodine (2/1), CHNO·I·0.5I, , and 4-[(benzyl-amino)-carbon-yl]-1-methyl-pyridinium triiodide, CHNO·I , , with different cation:iodine atoms ratios were studied. Salt contains one cation, one iodide anion and half of the neutral I mol-ecule in the asymmetric unit (cation:iodine atoms ratio is 1:2).
View Article and Find Full Text PDFActa Crystallogr E Crystallogr Commun
December 2021
Cubic crystals of tripotassium aluminium (or gallium) nitridotriphosphate, K (PO)N ( = Al, Ga), were grown by application of the self-flux method. In their isostructural crystal structures, all metal cations and the N atom occupy special positions with site symmetry 3, while the P and O atoms are situated in general positions. The three-dimensional framework of these oxidonitridophosphates is built up from [ O] octa-hedra linked together (PO)N groups.
View Article and Find Full Text PDFCrystallization of concomitant polymorphs is a very intriguing process that is difficult to be studied experimentally. A comprehensive study of two polymorphic modifications of acetyl 2-(-(2-fluorophenyl)imino)coumarin-3-carboxamide using quantum chemical methods has revealed molecular and crystal structure dependence on crystallization conditions. Fast crystallization associated with a kinetically controlled process results in the formation of a columnar structure with a nonequilibrium molecular conformation and more isotropic topology of interaction energies between molecules.
View Article and Find Full Text PDFThe photoelectrochemical properties of scheelite-related MBiVMoO (M = Ca, Sr, x = 0.1 to 0.9) solid solutions deposited on conductive glass (coated with SnO, F-doped) have been investigated as photoanodes in photoelectrochemical (PEC) water splitting.
View Article and Find Full Text PDFContinuing the search for new potential analgesics among the derivatives of 4-methyl-2,2-dioxo-1-2λ⁶,1-benzothiazine-3-carboxylic acid, the possibility of obtaining its esters by the alkylation of the corresponding sodium salt with iodoethane in dimethyl sulfoxide (DMSO) at room temperature was studied. It was found that under such conditions, together with the oxygen atom of the carboxyl group, a heteroatom of nitrogen is also alkylated. Therefore, the product of the reaction studied is a mixture of ethyl 4-methyl-2,2-dioxo-1-2λ⁶,1-benzothiazine-3-carboxylate (major) and its 1-ethyl-substituted analog (minor).
View Article and Find Full Text PDFHerein, the peculiarities of complex phosphate formation in self-fluxes of Cs-M-Bi-P-O (M = Ca, Sr, Ba and Pb) systems with Cs/P = 0.7-1.3 at fixed ratios of Bi/P = 0.
View Article and Find Full Text PDFActa Crystallogr C Struct Chem
November 2017
The known metal-CO structures may be divided into two modifications, α and β. The α-modification has an order-disorder struxture, revealing one-dimensional disordering of the metal-oxalate chains, and the β-modification is ordered. The crystal structures of orthorhombic γ-MnCO {poly[μ-oxalato-manganese(II)]; space group Pmna, a = 7.
View Article and Find Full Text PDFImportance: Patients carrying a C9orf72 repeat expansion leading to frontotemporal dementia and/or amyotrophic lateral sclerosis have highly variable ages at onset of disease, suggesting the presence of modifying factors.
Objective: To provide clinical-based evidence for disease anticipation in families carrying a C9orf72 repeat expansion by analyzing age at onset, disease duration, and age at death in successive generations.
Design, Setting, And Participants: This cohort study was performed from June 16, 2000, to June 1, 2016, in 36 extended Belgian families in which a C9orf72 repeat expansion was segregating.
We investigated the mutation spectrum of the TANK-Binding Kinase 1 (TBK1) gene and its associated phenotypic spectrum by exonic resequencing of TBK1 in a cohort of 2,538 patients with frontotemporal dementia (FTD), amyotrophic lateral sclerosis (ALS), or FTD plus ALS, ascertained within the European Early-Onset Dementia Consortium. We assessed pathogenicity of predicted protein-truncating mutations by measuring loss of RNA expression. Functional effect of in-frame amino acid deletions and missense mutations was further explored in vivo on protein level and in vitro by an NFκB-induced luciferase reporter assay and measuring phosphorylated TBK1.
View Article and Find Full Text PDFThe fact that molecular crystals exist as different polymorphic modifications and the identification of as many polymorphs as possible are important considerations for the pharmaceutic industry. The molecule of N-benzyl-4-hydroxy-1-methyl-2,2-dioxo-1H-2λ(6),1-benzothiazine-3-carboxamide, C17H16N2O4S, does not contain a stereogenic atom, but intramolecular hydrogen-bonding interactions engender enantiomeric chiral conformations as a labile racemic mixture. The title compound crystallized in a solvent-dependent single chiral conformation within one of two conformationally polymorphic P212121 orthorhombic chiral crystals (denoted forms A and B).
View Article and Find Full Text PDFThe influence of molybdenum content in the solid solutions of Bi1-x/3V1-xMoxO4 (x = 0.05-0.20) on the morphology, band gap, structure and light-driven water oxidation properties has been studied by scanning electron microscopy, X-ray powder diffraction and vibrational spectroscopy (Raman and infrared).
View Article and Find Full Text PDFObjective: To assess the genetic contribution of TBK1, a gene implicated in amyotrophic lateral sclerosis (ALS), frontotemporal dementia (FTD), and FTD-ALS, in Belgian FTD and ALS patient cohorts containing a significant part of genetically unresolved patients.
Methods: We sequenced TBK1 in a hospital-based cohort of 482 unrelated patients with FTD and FTD-ALS and 147 patients with ALS and an extended Belgian FTD-ALS family DR158. We followed up mutation carriers by segregation studies, transcript and protein expression analysis, and immunohistochemistry.
Pathological expansion of a G4C2 repeat, located in the 5' regulatory region of C9orf72, is the most common genetic cause of frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS). C9orf72 patients have highly variable onset ages suggesting the presence of modifying factors and/or anticipation. We studied 72 Belgian index patients with FTLD, FTLD-ALS or ALS and 61 relatives with a C9orf72 repeat expansion.
View Article and Find Full Text PDFActa Crystallogr E Crystallogr Commun
March 2015
The title compound, tetra-potassium tetra-[nickel(II)/iron(III)] penta-kis-(orthophosphate), K3.84Ni0.78Fe3.
View Article and Find Full Text PDFThe solid solution KNi(0.93)Fe(II)(0.07)Fe(III)(PO4)2 {potassium [nickel(II)/iron(II)] iron(III) bis(orthophosphate)} has been prepared by the flux method.
View Article and Find Full Text PDF