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Hamid Reza Shaterian Asghar Hosseinian Majid Ghashang Fahimeh Khorami Neda Karimpoor 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):2333-2338
An environmentally friendly procedure for the preparation of dihydropyrimidinone derivatives or their sulfur analogues under thermal solvent-free conditions in the presence of aluminium hydrogen sulfate [Al(HSO4)3] and alumina sulfuric acid (Al2O3-SO3H) as heterogeneous catalysts was developed. 相似文献
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Barbara Milczarska Henryk Foks Urszula Dobrzycka Zofia Zwolska Ewa Augustynowicz-Kopeć 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2793-2799
The 4-hydroxyalkyl-1,2,4-triazole-3-thiones cyclization allowed us to work out the effective method of 1,3-thiazacycloalkyl[3,2-b]-1,2,4-triazoles synthesis. Some of the compounds that were obtained were tested for their tuberculostatic activity. 相似文献
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Ryosuke Matsui Erina Niijima Tomomi Imai Hiroyuki Kobayashi Akiko Hori Azusa Sato Yuko Nakamura Osamu Kitagawa 《Molecules (Basel, Switzerland)》2022,27(7)
The halogen bond has been widely used as an important supramolecular tool in various research areas. However, there are relatively few studies on halogen bonding related to molecular chirality. 3-(2-Halophenyl)quinazoline-4-thione derivatives have stable atropisomeric structures due to the rotational restriction around an N-C single bond. In X-ray single crystal structures of the racemic and optically pure N-C axially chiral quinazoline-4-thiones, we found that different types of intermolecular halogen bonds (C=S⋯X) are formed. That is, in the racemic crystals, the intermolecular halogen bond between the ortho-halogen atom and sulfur atom was found to be oriented in a periplanar conformation toward the thiocarbonyl plane, leading to a syndiotactic zig-zag array. On the other hand, the halogen bond in the enantiomerically pure crystals was oriented orthogonally toward the thiocarbonyl plane, resulting in the formation of a homochiral dimer. These results indicate that the corresponding racemic and optically pure forms in chiral molecules are expected to display different halogen bonding properties, respectively, and should be separately studied as different chemical entities. 相似文献
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Reactions of copper(I) halides with racemic 2,2′-bis(diphenylphosphano)-1,1′-binaphthyl (rac-binap) in 1:1 molar ratio afforded mononuclear complexes of the type [CuX(rac-binap)] (X = Cl, Br, I) which, on further treatment with 1 equiv. of pyridine-2-thione (py2SH), pyrimidine-2-thione (pymtH) or 4,6-dimethyl-pyrimidine-2-thione (dmpymtH) gave rise to the formation of mixed-ligand complexes of the formula [CuX(rac-binap)(thione)]. The molecular structures of [CuBr(rac-binap)(py2SH)] · 2CH2Cl2, [CuBr(rac-binap)(py2SH)] · CH2Cl2 and [CuBr(rac-binap)(dmpymtH)] · CH2Cl2 have been established by single-crystal X-ray diffraction. Each of the complexes features a distorted tetrahedral copper(I) center with the phosphane acting in a chelating fashion. The complexes are strongly luminescent in the solid state at ambient temperature. Unusually, the [CuBr(rac-binap)(py2SH)] · 2CH2Cl2 molecules crystallise in a chiral space group with independent S- and R-enantiomers in the asymmetric unit. 相似文献
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Alejandro M. Fracaroli O. Fernando Silva Alejandro M. Granados Rita H. de Rossi 《Journal of Physical Organic Chemistry》2008,21(11):1007-1013
The UV–Vis spectrum of 5‐(1‐butylthio)‐3H‐1,2‐dithiole‐3‐thione (1a) and that of the chromium pentacarbonyl complex of 5‐methyl‐3H‐1,2‐dithiole‐3‐thione (3) present significant changes with the solvent polarity. The two absorption bands shown by the compounds in the region above 300 nm were identified by theoretical calculations. For Compound 1a these are n→π* and →π* transitions and for Compound 3 the longest wavelength absorption corresponds to a charge transfer band and shows a remarkably negative solvatochromism. Not only has the wavelength of maximum absorption changed with the solvent but also the ratio of the absorbances at the two wavelengths. The effect of solvents was correlated with solvatochromic parameters such as π* and α. The spectrum of 5‐(1‐butylthio)‐3H‐1,2‐dithiole‐3‐one ( 2 ) was also measured in different solvents but in this case the changes observed are less significant than for the other two compounds. The spectra of 1a and 3 were also determined in the presence of anionic (SDS), cationic (CTAB), and neutral surfactants (Brig‐35) and it is shown that these compounds can be used as probes for the polarity of the binding sites of organized assemblies. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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P. A. Ramazanova A. V. Tarakanova M. V. Vagabov V. V. Litvinova A. V. Anisimov 《Chemistry of Heterocyclic Compounds》2000,36(2):201-206
The reactions of 2-allylthiobenzimidazole, -oxazole, and-thiazole, and the thiones formed from them on heating, with dichlorocarbene have been investigated under phase transfer catalysis conditions.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 243–248, February, 2000. 相似文献
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Firouz Matloubi Moghaddam Mostafa Kiamehr Salman Taheri Zohreh Mirjafary 《Helvetica chimica acta》2010,93(5):964-973
An efficient synthesis of polycyclic indole derivatives is achieved via domino Knoevenagel–hetero‐Diels–Alder reaction of O‐acrylated salicylaldehyde derivatives with dihydroindole‐2‐thiones in H2O as solvent. The products are formed in good‐to‐excellent yields with high regio‐ and stereoselectivity. 相似文献
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Valerie Huemer Gernot A. Eller Wolfgang Holzer 《Magnetic resonance in chemistry : MRC》2010,48(6):476-482
Various [5,6]pyrano[2,3‐c]pyrazol‐4(1H)‐thiones were synthesized in high yields by treatment of the corresponding [5,6]pyrano[2,3‐c]pyrazol‐4(1H)‐ones with Lawesson's reagent. Detailed NMR spectroscopic studies were undertaken of the title compounds. Complete and unambiguous assignment of chemical shifts (1H, 13C, 15N) and coupling constants (1H,1H; 13C,1H) was achieved by the combined application of various one‐ and two‐dimensional (1D and 2D) NMR spectroscopic techniques. Unequivocal mapping of most 13C,1H spin coupling constants is accomplished by 2D (δ, J) long‐range INEPT spectra with selective excitation. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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