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951.
Maria Kucharska-Zon Jerzy Zon 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract Many complexes of 1-aminoakylphosphonic acids have been obtained and their structures have been studied [1–3]. On the other hand, 2-aminoindan-2-phosphonic acid (2-AIP), the phosphonic conformationally restricted cyclic analogue of phenylalanine, has been recently obtained [4]. We undertook a study of interaction of cobalt(II), nickel(II), and copper(II) with 2-AIP, to learn how the rigid Iigand structure influences the complexes structure. 相似文献
952.
George N. Nikonov Anna S. Balueva Elvira I. Musina Katherine V. Kovalenko Sergei V. Bobrov 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):821-823
The methods of synthesis and space structure of phosphorus-containing compounds, in which stacking conformation is realized, are considered. It is shown that intramolecular stacking can be observed in monoheterocyclic compounds, bi-and polycyclic compounds, complexes of metals and acyclic compounds. 相似文献
953.
Wiesław Sulkowski Anna Sułkowska Viatsheslav Kireev 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract The presence of trace of chlorine in poly(diorganophosphazenes) [-N=P(OR)2-]., where R = C2H5, CH2CF3, C2F5, C4H5, C6H13, C8H17, C12H25, CH2C6H5 in many cases leads to the substantial changes of their physicochemical properties and limits application possibilities of this class of polymers especial for the medical materials. Despite the optimization of reaction conditions for each nucleophilic alkoxy substituent, the obtained poly(dia1koxyphosphaenes) exhibited some physicochemical anomalies. 相似文献
954.
Jerzy Zakrzewski Maria Krawczyk 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1880-1903
Thio and seleno analogs of fenuron, isoproturon, chlorotoluron, metoxuron, monuron, and diuron were synthesized from the corresponding aryl amines. Their reaction with thiophosgene leads to isothiocyanates. Aryl amines were also converted (via isocyanides) to isoselenocyanates. The reaction of both isothio- and isoselenocyanates with dimethylamine affords the corresponding thio and seleno analogs of the above-mentioned urea herbicides. Herbicidal activity of the synthesized compounds was slightly lower than the activity of the parent urea herbicides. The thio and seleno analogs as well as the parent ureas showed good fungicidal activity at a concentration of 200 ppm against selected fungi. 相似文献
955.
956.
Damir A. Safin Maria G. Babashkina Michael Bolte Axel Klein 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2426-2432
The reaction of O,O′-diisopropylphosphoric acid isothiocyanate (iPrO)2P(O)NCS with 2-methylaniline 2-MeC6H4NH2, 2,6-dimethylaniline 2,6-Me2C6H3NH2, or 2,4,6-trimethylaniline 2,4,6-Me3C6H2NH2 leads to the N-phosphorylated thioureas RNHC(S)NHP(O)(OiPr)2 (R = 2-MeC6H4?, HLI ; 2,6-Me2C6H3?, HLII ; 2,4,6-Me3C6H2?, HLIII ). Reaction of the potassium salts of HLI –III with Ni(II) in aqueous EtOH leads to [Ni(LI–III-N,S)2] ([NiLI–III 2 ]) chelate complexes. The compounds obtained were investigated by 1H, 31P{1H} NMR spectroscopy and microanalysis. The molecular structure of the thiourea HLIII was elucidated by single crystal X-ray diffraction analysis. Single crystal X-ray diffraction studies showed that HLIII forms both intra- and intermolecular hydrogen bonds, which in turn leads to the formation of polymeric chains. One of the intermolecular hydrogen bonds is of the type N?H…S. Moreover, the formation of intermolecular C?H…η6-phenyl interactions was established. 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
957.
Taibi Ben Hadda Fatim Z. Khardli Mostafa Mimouni Maria Daoudi Abdelali Kerbal Héctor Salgado-Zamora 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):753-761
AbstractA series of four different armed heterocyclic candidates; 1-(2-methyl-2,3-dihydro-1,3-benzothiazol-2-yl)acetone (2), 1-(3-methyl-4H-1,4-benzothiazin-2-yl)ethanone (3), 2-[(2-aminophenyl)dithio]aniline (4), and 3-hydroxy-3-methyl-4-(3-methyl-2-quinoxalinyl)-2-butanone (5) have been prepared and their microbial activities were evaluated. A correlation of the structure and activities relationships of these compounds with respect to molecular modeling, Lipinski Rule of Five, drug likeness, toxicity profiles, and other physico-chemical properties of drugs are described and verified experimentally. 相似文献
958.
Elena O. Alonso Maria E. R. Marcondes Vicente G. Toscano 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4)
Abstract As part of our continuing interest in the mechanistic photochemistry of phosphonium salts (Toscano et al., Chez. Commun., 567 (1973); J. Phys. Chem., 83(9), 1213 (1979)) we have investigated the photodecomposition (313 nm irradiation) of (1-naphthyl-methyl) triphenylphosphonium (I) chloride and tetrafluoroborate in deaerated isopropanol: 相似文献
959.
Giovanna Delogu Ottorino De Lucchi Maria Paola Fois Giovanni Valle 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):417-425
Abstract Ketimines la-d derived from ortho-aminosubstituted phenylthioethers were prepared in order to determine the degree of chirality transfer from the chiral auxiliary to the sulfur atom in the formation of the sulfoxide or to the α-carbon atom in the reaction of the anion with alkyl halides or benzaldehyde. Oxidation to the sulfoxide occurred with little or no asymmetric induction. The crystalline benzyl sulfone 4c was deprotonated by alkyllithium or Grignard reagents and reacted with alkyl halides and benzaldehyde, in all cases with little to fair transfer of chirality. The major diastereoisomer from methylation of the anion of 4c with methyl iodide, was isolated, and afforded the enantiomerically pure amine 5 after removal of the chiral auxiliary. An X-ray structure determination of 4d allowed the assignment of the absolute configuration of the asymmetric carbon and revealed that the conformation of the ketimine in the crystal state is not homogeneous. 相似文献
960.
Paul M. Cullis Anna Iagrossi Andrew J. Rous 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):559-562
Abstract The stereochemical courses of phosphoryl transfer reactions in aprotic solvents and thiophosphoryl transfer reactions in protic solvent have been determined. The extensive racemisation observed in both instances is discussed in terms of metaphosphate and thiometaphosphate intermediates of significant life-times. 相似文献