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121.
《Journal of Coordination Chemistry》2012,65(7):759-775
The interaction of tin(II) and tin(IV) chlorides with norfloxacin (NOR) has been investigated. Elemental analysis, infrared, mass spectra and thermal analysis have been used to characterize the isolated solid complexes. The results support the formation of complexes with the formula [Sn(NOR)2]Cl2·4H2O and [Sn(NOR)3]Cl4. The infrared spectra of the isolated solid complexes suggested that NOR act as bidentate ligand through the carbonyl oxygen atom and one oxygen atom of the carboxylic group forming six-membered rings with the tin ions. The interpretation, mathematical analysis and evaluation of kinetic parameters of thermogravimetric (TGA) and its differential (DTG), such as entropy of activation, pre-exponential factors, activation energy evaluated by using Coats–Redfern and Horowitz–Metzger equations are carried out for two complexes. The data obtained indicate that the two complexes decompose in one stage and general mechanisms describing the decomposition are suggested. Furthermore, the electronic, and 1H?NMR spectra have been studied. 相似文献
122.
A method for the synthesis of 2-substitutedN, N′-diacylimidazolidines was developed. The method is based on the reactions of acylating reagents (carboxylic acid chlorides
and anhydrides, sulfonic acid chlorides, a carbamic acid chloride, and ethyl chlorocarbonate) with Schiff's bases prepared
by the reaction ofN-acylethylenediamines with aldehydes.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya. No. 5, pp. 896–900, May, 2000. 相似文献
123.
《Arabian Journal of Chemistry》2021,14(11):103396
Two new series of bis-thiazoles 6a-f and bis-thiazolones 9a-d were prepared via reacting bis-thiosemicarbazone 3 with hydrazonoyl chloride derivatives 4a-f and 7a-d, respectively, in dioxane under basic conditions. Another group of bis-thiazole derivatives 12a-h was prepared by reacting bis-thiosemicarbazone 3 with each of phenacyl bromide derivatives 10a-h under a similar reaction protocol. A plausible mechanism was proposed. Structural elucidation of the new products was established using both elemental and spectrometric/spectroscopic analyses. Structural, electronic, and the pharmacological characteristics of the prepared molecules were investigated with DFT calculations. Antibacterial and antifungal activities of the new bis-thiazoles were screened and compared with vancomycin and amphotericin B as antimicrobial standards. Molecular docking studies on the promising candidate compounds, with the lowest minimum inhibitory concentrations (MIC), were performed with SAP2 of C. albicans and FabI of S. aureus and P. aeruginosa. 相似文献
124.
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126.
Investigation of the antitumour activity of a series of diorganotin dichloride complexes (4-ZC6H4)2SnCl2·L2, where Z = OMe, Me, F, Cl, and CF3 and L2 = 2,2′-bipyridyl (bipy), 1,10-phenanthroline (phen) and 2-aminomethylpyridine (amp) is reported. A number of these complexex are shown to exhibit reproducible activity in vivo towards P388 lymphocytic leukaemia in mice. 1H NMR data are reported for an extended series of (4-ZC6H4)4Sn and the parent dichlorides (4-ZC6H4)2SnCl2 of the above-mentioned complexes. A correlation is reported between Hammett substituent constants and 1H chemical shift data. Attempts are made to relate the antitumour activity of the complexes to various structural factors. The dependence of antitumour activity on the electronic effect of group Z and the nature of the ligand L2 is demonstrated. 相似文献
127.
Ternary Chlorides in the Systems NaCl/HoCl3 and NaCl/ErCl3 Phase diagrams of the systems NaCl/HoCl3 and NaCl/ErCl3 were determined by means of DTA and high-temperature XRD. There exist compounds Na3LnCl6, NaLnCl4 (Ln ? Ho, Er) and NaHo2Cl7. NaHoCl4 undergoes a phase transition at 374°C from the NaGdCl4? to the NaErCl4? type of structure. The thermodynamic functions for the formation of the compounds from NaCl and LnCl3 were determined by solution calorimetry and e.m.f. measurements in galvanic cells for solid electrolytes. The compounds NaLnCl4 are the most stable ones. 相似文献
128.
Mehdi Adib Rahim Pashazadeh Saideh Rajai-Daryasarei Fatemeh Moradkhani Mehdi Jahani Seyed Jamal Addin Gohari 《Tetrahedron》2018,74(28):3858-3870
Efficient TBHP/R4N+X– promoted hydroaroylations of dialkyl azo-1,2-dicarboxylates with methyl arenes, aldehydes, aryl methanols and arylmethyl chlorides are described. These oxidation/oxygenation and hydroaroylation processes were carried out by tert-butyl hydroperoxide as terminal oxidant/oxygen source, and were catalyzed by tetrabutylammonium bromide and tricaprylmethylammonium chloride as the driving force. During this investigation, all these hydroaroylating sources were found to be highly efficient reagents without the need of any transition-metal. 相似文献
129.
Visible‐Light‐Promoted Synthesis of 1,4‐Dicarbonyl Compounds via Conjugate Addition of Aroyl Chlorides 下载免费PDF全文
A facile visible‐light photocatalytic conjugate addition to prepare 1,4‐dicarbonyl compounds has been developed by employing readily available aroyl chlorides as aryl radical sources. This operationally simple method shows a broad scope with regard to both aroyl chlorides and Michael acceptors. As a result, a variety of 1,4‐diketones were efficiently synthesized in moderate to good yields. 相似文献
130.
Gigliola Lusvardi Ledi Menabue Monica Saladini 《Journal of chemical crystallography》1995,25(11):713-716
The coordination behavior of N-tosyl-L-glutamine (hereafter abbreviated as tsglnH, tosyl =toluenesulfonyl group) toward the Zn(II) ion is investigated by means of structural and spectroscopic techniques. From aqueous solution, at acidic pH the Zn(II) ion separates a compound of empirical formula Zn(tsgln)2·2H2O whose crystal structure is determined. The crystal is monoclinic, space group C2, with cell dimensions:a=19.775(5),b=5.3146(3),c=16.543(8) Å, =119.93(3)°,Z=2. The Zn(II) is tetrahedrally coordinated by two symmetry-related tsgln monoanions acting as monodentate carboxylate ligands and two symmetry related water molecules. The Zn–O bond distances are similar while the angles at Zn(II) ion differ significantly from those of regular tetrahedron. The side chain amide group does not participate in metal coordination and forms intermolecular hydrogen bonds. 相似文献