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121.
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
122.
Wu Tang Zhi-Hua Yu De-Qing Shi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2024-2029
Target compounds 3 were synthesized by the condensation of O,O-diethyl α-amino substitutedbenzyl phosphonates 1 and 4-methyl-[1,2,3]thiadiazole-5-carboxylic acid 2 in the presence of dicyclohexylcarbodiimide (DCC) as a dehydration reagent. Their structures were confirmed by spectroscopic data (IR, 1H NMR, 31P NMR, MS) and elemental analysis. The results of a preliminary bioassay (in vitro) indicated that some of the title compounds 3 possessed moderate to good herbicidal activities against dicotyledonous plants (Brassica campestris L) at the concentration of 100 mg/L, and most of these compounds exhibited higher herbicidal activities against dicotyledonous plants (Brassica campestris L) than monocotyledonous plants (Echinochloa crus-galli). 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
123.
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
124.
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
125.
Wagnat W. Wardakhan Hatem M. Gaber Salama A. Ouf Sherif M. Sherif 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):601-618
Abstract Heterocyclic enamines1 reacted with ethyl acetoacetate to afford the corresponding amide derivatives2. Treatment of2 with carbon disulphide yielded the dipotassium salts3which reacted in-situ with a variety of α -haloketones to give the respective substituted thiophenes5,8, and13. The reactivity of the latter products towards various chemical reagents was studied to yield their fused thiophene derivatives7,10,12, and14, respectively. Some representative compounds were tested for antimicrobial activity. 相似文献
126.
Harika Patnala Hanna S. Abbo Krishna Murthy Potla 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):1035-1039
AbstractAn efficient and eco-friendly protocol has been accomplished for a series of novel α-diaminophosphonates by a one-pot, three-component system via Kabachnik-Fields reaction of 4,4′-methylenedianiline, a variety of aryl/heteroaryl aldehydes and diphenylphosphite employing polyethylene glycol (PEG-400) as a green solvent at 80?°C. All products were obtained in good to excellent yields (80–95%). The identity of the new synthesized compounds was confirmed by IR, 1H, 13C, and 31P NMR, LC-MS and elemental analysis. In vivo anti-viral activity was evaluated against tobacco mosaic virus (TMV). Compounds 4b, 4c, 4j and 4k exhibited the highest anti-viral activities against tobacco mosaic virus (TMV) when compared with the standard drug ningnanmycin. 相似文献
127.
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
128.
Hua Fang Xuanling Xie Bihong Hong Yufen Zhao Meijuan Fang 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2145-2155
Abstract A method for the synthesis of α-aminophosphonates through the three-component coupling reaction of aldehydes, amines, and diisopropyl phosphite using copper (I) iodide salt catalyst is demonstrated, The reaction is highly efficient, economic, and also environment friendly. [Supplemental 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 resource: Table S1, Figures S1–S9.] GRAPHICAL ABSTRACT 相似文献
129.
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
130.
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