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921.
N. N. Golovnev N. G. Naumov A. A. Bakhtina A. O. Lykhin 《Journal of Structural Chemistry》2010,51(5):980-983
A new compound C17H22FN3O3
2+ ZnCl4
2 (pefloxacindium tetrachlorozincate(II)), C17H20FN3O3 1-ethyl-N-methyl-6-fluoro-1,4-dihydro-4-oxo-7-(4-methyl-1-piperazinyl)-3-quinoline carbonic acid (PefH, pefloxacin) is synthesized,
and its crystal structure is determined. The crystal contains PefH3
2+ and ZnCl4
2− ions. The supramolecular architecture of the crystal is analyzed. 相似文献
922.
N. G. Naumov S. Cordier D. S. Ovoschnikov D. Y. Naumov S. B. Artemkina C. Perrin V. E. Fedorov 《Journal of Cluster Science》2009,20(1):213-223
Two isomers (cis and trans) of [Nb6Cl9O3(NCS)6]5– niobium cluster complexes characterized by an ordered arrangement of oxygen and chlorine ligands over the 12 inner positions
in the cluster core were prepared by reaction of Cs2LaNb6Cl15O3 and ScNb6Cl13O3 solid state compounds with aqueous solution of potassium thiocyanate. The cis and trans isomers (idealized C
2
v
and D
3 symmetry, respectively) crystallize with counter cations and water molecules to form the following salts: Cs4.75K0.25[Nb6Cl9O3(NCS)6] · 5.5H2O (1) and Cs2.5K2.5[Nb6Cl9O3(NCS)6] · 2H2O (2), respectively. The trans isomer is ordered in structure 1 (s.g.: C2/c), while in the structure of 2 (s.g.: Pnma), the cis isomer is randomly disordered over two positions that correspond one to each other by a mirror plane. Interestingly, the
treatment of thiocyanato complexes cis and trans with hydrochloric acid led to substitution of (NCS)– ligands by Cl– and to formation of soluble complexes [Nb6Cl9O3Cl6]5–. The cesium salt of trans-[Nb6Cl9O3Cl6]5– was crystallized as Cs5[Nb6Cl15O3] · CsCl · 7H2O (3) and structurally characterized. Indeed, the formation of soluble [Nb6Cl9O3(NCS)6]5– intermediates is a necessary step towards the formation of soluble anions. 相似文献
923.
The influence of a water-acetone solvent on the stability of nickel(II) complexes with glycylglycine
V. A. Isaeva V. V. Naumov V. A. Sharnin 《Russian Journal of Coordination Chemistry》2009,35(11):868-870
The stability constants of nickel(II) complexes with glycylglycine in water-acetone mixtures (mole fraction of acetone X = 0–0.40) were determined by potentiometric titration at 298 K and an ionic strength of 0.1 M (NaClO4). With an increase in the content of the organic cosolvent, nickel(II) glycylglycinates become more stable, mainly because
of the better coordination of the ligand through the carboxy group. 相似文献
924.
Dr. Durga Prasad Karothu Zainab Alhaddad Dr. Christian R. Göb Dr. Christian J. Schürmann Dr. Robert Bücker Prof. Panče Naumov 《Angewandte Chemie (International ed. in English)》2023,62(26):e202303761
Levocetirizine is an orally administrated, second-generation antihistaminic active pharmaceutical ingredient that has been used to treat symptoms of allergy and long-term hives for over 25 years. Despite the wide use of this compound, its crystal structure has remained unknown. Here we report the application of 3D electron diffraction (3D ED)/Micro-crystal electron diffraction (MicroED) to determine the crystal structure of Levocetirizine dihydrochloride directly from crystalline powders that were extracted from commercially available tablets containing the compound. We also showcase the utility of dynamical refinement to unambiguously assign absolute configuration. The results highlight the immense potential of 3D ED/MicroED for structure elucidation of components of microcrystalline mixtures that obviates the need to grow large-size single crystals and the use of complementary analytical techniques, which could be important for identification as well as for primary structural characterization. 相似文献
925.
A. S. Ionkin S. N. Ignat'Eva I. A. Litvinov V. A. Naumov B. A. Arbuzov 《Heteroatom Chemistry》1992,3(4):459-461
A dimer of thioxo-N-t-butylimino(trimethylsiloxy)-phosphorane 5 has been prepared by reaction of tris(trimethylsilyl) phosphine with N-sulfinyl-N-tert-butylamine. The structure of 5 has been confimed by X-ray analysis data. 1-Aza-2-thia-3-phosphaallene 1 , thiaphosphaziridine 3 , iminophosphine P-sulfide 4 are postulated as intermediates of the reaction studied. 相似文献
926.
Ryabov D. S. Chechin G. M. Naumov E. K. Bebikhov Yu. V. Korznikova E. A. Dmitriev S. V. 《Nonlinear dynamics》2023,111(9):8135-8153
Nonlinear Dynamics - All possible one-component delocalized nonlinear vibrational modes (DNVMs) in a square lattice are analyzed. DNVMs are obtained taking into account exclusively the symmetry of... 相似文献