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991.
Valeriya A. Startseva Olga A. Lodochnikova Alexander E. Klimovitskii Alexander V. Aref’ev Nadezhda P. Artemova 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):615-629
Abstract The oxidation of a β-hydroxysulfide in the pinane series by use of m-chloroperbenzoic acid resulted in the formation of the corresponding β-hydroxysulfoxide as a mixture of two diastereomers in 4:5 ratio. According to single-crystal X-ray diffraction (XRD) results, it is established that the diastereomeric mixture of sulfoxides crystallizes in the “racemic compound-like” manner under formation of asymmetric dimers through S=O··H–O interactions. This asymmetric dimer formed from diastereomeric molecules is a structural unit in both crystal modifications, the triclinic and the monoclinic one. The behavior of the diastereomeric mixture of pinane derived sulfoxides in crystals, melts and in tetrachloromethane solutions was studied by IR spectroscopy. The density functional theory (DFT) method with 6-31G (d, p) basis set was used to calculate the optimized geometrical parameters and vibrational frequencies of different associates in solutions. The calculated vibrational frequencies are compared with experimental IR spectra. 相似文献
992.
Thressa C. Stadtman 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):199-216
Abstract Some enzymes known to contain selenium are enumerated. In four of them which catalyze coupled oxidation-reduction reactions the selenium occurs exclusively in the form of selenocysteine residues. Their structure and function are described in detail. Two other bacterial enzymes which contain selenium in the form of a labile, readily dissociable component are also described. Results on the isolation, identification and structure determination of selenium-containing amino acid transfer ribonucleic acids are presented. These seleno-t RNA's are shown to contain either 5-methyl-aminomethyl-2-selenouridine or other 2-selenouridine derivatives. The role of selenium in a glutamate iso-accepter species is discussed. 相似文献
993.
Amit C. Patel Dharmesh H. Mahajan Kishor H. Chikhalia 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):368-376
A new series of 2-(coumarin-3-yl)-5-mercapto-1,3,4-oxadiazoles based on various aryl thiourea/ureas incorporating a 1,3,5-s-triazine moiety is reported. The components of this series have been obtained by the reaction of cyanuric chloride (1) with 2-(coumarin-3-yl)-5-mercapto-1,3,4-oxadiazole (2). The prepared 2-{(coumarin-3-yl-1,3,4-oxadiazolyl)-5-thio}-4,6-dichloro-s-triazine (3) was subsequently treated with morpholine (4) to form 2-{(coumarin-3-yl-1,3,4-oxadiazolyl)-5-thio}-4-(morpholino)-6-chloro-s-triazine (5). This was further treated with various substituted aryl urea/thioureas (6a–k/7a–k) to afford the title compounds 8a–k and 9a–k, which were and tested for their antibacterial activity (MIC) against different microorganisms. The structures of the novel synthesized compound have been established on the basis of 1H NMR and FT-IR data together with elemental analysis. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献
994.
Antonio Alivert Jorge Bujons Juan-Julio Bonet 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4):205-207
Abstract The treatment of 2-acetylthiophene with phosphorus pentachloride led, besides other products reported in previous studies, to 2-(2-thienyl)-2-chloroethenephosphonic acid in 16% yield. This compound was transformed, in the course of purification attempts, into 2-(2-thienyl)-2-oxoethanephosphonic acid. Full spectroscopic data for both compounds are provided. 相似文献
995.
Dejiang Li Deqing Long Heqing Fu 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):519-526
1,3-bis[(3-aryl)-s-triazolo[3,4-b]-[1,3,4]thiadiazole-6-yl]benzenes 2 were synthesized in high yields by the reaction of 3-aryl 4-amino-5-mercapto-1,2,4-triazole 1 with m-phthalic acid. 相似文献
996.
S. Santhi Sudha Ch. Syama Sundar N. Bakthavatchala Reddy K. Uma Maheswara Rao S. H. Jaya Prakash C. Suresh Reddy 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):1402-1411
Abstract A simple, efficient, and environmentally benign methodology has been accomplished for the synthesis of α-aminophosphonates by one-pot three-component reaction of ethyl-2-amino-α-(methoxy-imino)-4-thiazoleacetate, aldehydes, and diethylphosphite by using Amberlyst-15 as catalyst at room temperature under solvent-free conditions. Their chemical structures were characterized by infrared (IR), NMR (1H, 13C & 31P), mass spectral, and elemental analysis. All the title compounds were screened for radical-scavenging activity by 1,1-diphenyl-2-picrylhydrazyl (DPPH), nitic oxide (NO), and hydrogen peroxide (H2O2) methods. Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental files: Additional text and figures. 相似文献
997.
Boris I. Usachev Vyacheslav Ya. Sosnovskikh Mikhail A. Shafeev Gerd-Volker Röschenthaler 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5-6):1315-1319
Abstract Alkyl 2-mercaptophenyl ketones react with trifluoroacetic anhydride in the presence of triethylamine to give 2-(trifluoromethyl)-4H-thiochromen-4-ones, which are transformed into the corresponding pyrazoles by treatment with hydrazine hydrate and into 1,1-dioxides by oxidation with H2O2 in AcOH. 相似文献
998.
E. Karthikeyan S. Perumal s. Selvaraj 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2379-2386
Diastereoselective synthesis of a series of (Z)-1-[3-aryl-2-(phenylsulfanyl)-2-oxiranyl]-1-ethanones was effected from the reaction of (Z)-4-aryl-3-(phenylsulfanyl)-3-buten-2-ones with alkaline hydrogen peroxide in tetrahydrofuran. The stereochemistry of the oxiranes has been deduced from two-dimensional NOESY spectrum. 相似文献
999.
Türsen Demir Frederick J. Raveney Robert A. Shaw 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):155-163
Abstract The reactions of 4-methyl-2-[N-(p-toluidinyl)methyl]aniline with phosphorus oxychloride, thiophosphoryl chloride, and their derivatives yield 1,3,2-benzodiazaphosphorine 2-oxides and 2-sulphides. Their 1H NMR and infrared spectra are discussed. Related 1,3,2-benzodiazophosphorine and 1,3,2-dibenzodiazaphosphocine 2-oxides and 2-sulphides are compared. 相似文献
1000.
Shabbir Hussain Saqib Ali Saira Shahzadi Saroj K. Sharma Kushal Qanungo Muhammad Altaf 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):542-551
Abstract Organotin complexes with the general formulae R2SnL2, R2Sn(Cl)L, and R3SnL have been synthesized where R = CH3, n-C4H6, C6H5, C6H11, and L = 4-(hydroxy methyl)piperidine-1-carbodithioic acid. The newly synthesized complexes have been characterized by elemental analysis, IR, NMR (1H, 13C and 119Sn), and, for one example, a single crystal x-ray structure. The FT-IR data shows the bidentate nature of the ligand. This coordination behavior is also confirmed by semi-empirical study. In the solid state, diorganotin complexes exhibit the penta/hexacoordinated geometry, whereas the triorganotin(IV) complexes show the five coordinated geometry. 119Sn NMR data reveal that triorganotin(IV) complexes exhibit the four coordinated geometry in solution, whereas the diorganotin(IV) compounds show the higher coordination, probably five or six. X-ray diffraction analysis of complex (2) shows a square pyramidal geometry around the tin atom on the basis of τ value. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. GRAPHICAL ABSTRACT 相似文献