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41.
A. A. F. Wasfy M. S. Amine M. M. H. Arief S. G. Donia A. A. Aly 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):1359-1368
4-(5,5-Dioxodibenzothiophen-2-yl)-4-oxo-2-butenoic acid ( 1 ) was condensed with compounds containing active methylene groups under Michael reaction conditions to form the Michael adducts 2a-c , 3a-c , and 4a-b . The behavior of Michael adduct towards the action of hydrazine hydrate was investigated. The compounds were tested for biological properties. 相似文献
42.
43.
Zhifu Jiang Jian Zhao Beibei Gao Shuo Chen Wenyan Qu Xiangdong Mei 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1026-1037
Abstract A series of novel (4′-tosyl) piperidin-4-yl containing α-aminophosphonates were synthesized by a one-pot reaction, efficiently catalyzed by magnesium perchlorate, under solvent-free conditions from 1-tosylpiperidin-4-one, substituted aromatic amines, and diethyl phosphite (DEP). The synthesized compounds were characterized by IR, 1H NMR, 13C NMR, 31P NMR, and HRMS spectroscopy. A single-crystal X-ray structure of diethyl 4-(2-chlorophenyl) amino-1-(4’-methylbezenesulfonyl) piperidin-4-yl-phosphonate (2a) was obtained, and some of the title compounds displayed insecticidal activities against Plutella xylostella. Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfer, and Silicon and the Related Elements for the following free supplemental files: Additional figures and tables. 相似文献
44.
Zhi-Hua Yu De-Qing Shi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2316-2323
In order to find novel pyrimidinyl carboxylic acid analogs with high activity and low toxicity, a series of novel pyrimidinyl derivatives containing an α-amino phosphonate moiety 5 was synthesized by the condensation of 4-(4,6-dimethoxypyrimidin-2-yloxy)phenoxyacetic 3a or propionic acids 3b with dialkyl α-amino substitutedbenzyl phosphonates 4. Their structures were characterized by spectroscopic data (IR, 1H NMR, 31P NMR, MS) and elemental analyses. The results of preliminary herbicidal activities (in vitro) showed that most of these compounds exhibited higher herbicidal activities against dicotyledonous weeds (Brassica campestris L) than monocotyledonous weeds (Echinochloa crus-galli). Further bioassays (in vivo) indicated that some of compounds 5 possessed selective herbicidal activity against amaranth pigweed (A. retroflexus) in post-emergence treatment. 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
45.
Ch. Syama Sundar N. Bakthavatchala Reddy S. Siva Prasad K. Uma Maheswara Rao S. H. Jaya Prakash C. Suresh Reddy 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4):551-557
Abstract A new series of α-aminophosphonates have been synthesized by a one-pot three-component reaction of 2,3-dihydrobenzo[b][1,4]dioxine-6-carbaldehyde, various amines, and dimethyl phosphite by using nano-TiO2 as a catalyst under solvent-free conditions at 50°C. The major advantages of the present method are high yields, short reaction times, recyclable catalyst, and solvent-free reaction conditions. Among these new structurally diversified set of α-aminophosphonates, dimethyl (2,3-dihydrobenzo[b][1,4]dioxin-6-yl)(3-nitrophenylamino) methylphosphonate and dimethyl (2,3-dihydrobenzo[b][1,4]dioxin-6-yl)(4-fluoro-3-nitro-phenyl-amino) methylphosphonate have shown higher antioxidant activity in diphenyl picryl hydrazyl (DPPH) scavenging, reducing power assay, and lipid peroxidation methods. 相似文献
46.
Mohammed A. Assiri Mamdouh M. Ali I. S. Yahia 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):668-674
AbstractThe synthesis of some novel chromonyl and pyrazolyl α-aminophosphonates containing a quinazolinone ring was carried out by applying Pudovik and Kabachnik-Fields reactions under solvent- and catalyst-free conditions. The anticancer activities of these compounds were evaluated against five cancer cell lines. 3-{[(3-Phenyl/1,3-diphenyl-1H-pyrazol-4-yl)methylidene]amino}-2-phenyl-quinazolin-4(3H)-ones (3d,e) and diethyl {[3-phenyl/1,3-diphenyl-1H-pyrazol-4-yl][(4-oxo-2-phenyl-quinazolin-3(4H) yl)amino] methyl}phosphonates (4d,e) displayed the potent anticancer activities against HCT116, MCF-7 and HepG2 cell lines in comparison with the standard drug. 相似文献
47.
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
48.
Bianca F. Bonini Mauro Comes-Franchini Mariafrancesca Fochi Germana Mazzanti 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):451-452
α-Silyl Vinylsulfides, obtained in a stereoselective manner through enethiolizable silyl thioketones, can be used for the synthesis of vinylsulfides and vinylsilane with a specific geometry, and for the preraration of bicyclic and open chain thiofunzionalized enones. 相似文献
49.
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
50.
P. V. Badadhe N. M. Chavan D. S. Ghotekar P. G. Mandhane R. S. Joshi C. H. Gill 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2021-2032
Abstract Synthesis of some new functionalized thiazolidin-4-ones and α-amino phosphonate derivatives has been reported. The imines were synthesized from the reaction of various substituted anilines with 1-phenyl-3-(pyridine-4-yl)-1H-pyrazole-4-carbaldehyde in ethanol at reflux condition. The corresponding thiazolidin-4-ones and α-aminophosphonates were prepared by reaction of imines with mercaptoacetic acid and triethyl phosphite, respectively. The structures of the newly synthesized compounds were confirmed by IR, 1H NMR, and mass spectral data and were evaluated for their antimicrobial activities. GRAPHICAL ABSTRACT 相似文献