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961.
962.
963.
Vanya B. Kurteva Maria J. Lyapova 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):239-249
Abstract Reaction of 3-amino- or 3-methylamino-1,2,3-triphenylpropyl chlorides (6 or 7) with potassium ethylxanthate leads to 4.5.6-triphenyl-tetrahydro-,3-thiazine-2-thione 1 or 1-methyl-2,3,4-triphenylazetidine 8 depending on the N-substitution. Conformational distribution of all possible diastereoisomeric thiazinethiones 1 and their N-alkyl derivatives 2–5 is determined by means of 1H NMR spectroscopy. Allylic strain caused by N- substituents in the trans,cis-isomers strongly shifts the equilibrium between conformations with a,a,e or e,e,a phenyl groups towards the conformer with an axial neighbouring Ph-4 group. Vicinal couplings data for the diastereoisomeric azetidine 8 show different ring geometry depending on the configuration. 相似文献
964.
965.
Grażyna Bartkowiak Elżbieta Wyrzykiewicz Grzegorz Schroeder Anna Walkowiak Anna Szponar Ilona Pawlak 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1429-1436
Eighteen new 2,4-di-ortho- (meta- and para-) bromo-(chloro- and nitro-)benzylthio-5-bromouracils (and 6-methyluracils) have been prepared. The structures of these compounds were confirmed by spectral (IR, UV/vis, 1H NMR) and elemental analyses. Estimation of pharmacotherapeutic potential has been made for synthesized compounds on the basis of prediction of activity spectra for substances (PASS). 相似文献
966.
Anna Matveeva Zoya Starikova Margarita Passechnik Irina Odinets Tatyana Mastryukova 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8-9)
The enols R 1 R 2 P(E)(CN)C = CR 3 OH (E = O or S) gave in solutions either neutral metal complexes ML x or M(OH) y L x . The anionic ambidentate ligands are coordinated through E and O atoms in solutions, and O, E, and N atoms in in crystals. 相似文献
967.
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
968.
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
969.
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
970.
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