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131.
Fatma S.M. Hassan 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):406-417
Complexes of the type [Pt R2 (dppma-PP′)] (R─Me, Et, Ph, CH2Ph, C6H4 Me-p, C6H4OMe-2, CH2CMe3, 1-naphthyl, C6H4Me-o, dppma = Ph2PNMe PPh2) have been prepared from [PtCl2, (dppma-PP′)] and the corresponding alkyl-lithium or Grignard reagents. Equilibrium constants, k, for the conversion of [PtR2 (dppma-PP′)] into cis-[PtR2(dppma-P)2] with dppma were studied using 31P NMR spectroscopy at room temperature. Equilibrium is rapidly established for R─C6H4-Me-o, at 20°C. Complex of the type cis-[PtR2 (dppma-P)2] was isolated R─C6H4 Me-o. The complexes [PtMe2(dppma-P)2] and [Pt(o-methoxyphenyl)2(dppma-P)2] were prepared, but unfortunately decomposed once isolated, the only evidence for its formation being from 31P-{1H} NMZR spectroscopy. The o-tolyl or 1-naphthyl complexes exist as syn-anti mixtures in solution, due to restricted rotation around the platinum aryl bonds. Treatment of several complexes of the type [PtR2(dppma-PP′)] with MeI gives [PtR2Me(I)(dppma-PP′)] with trans addition of MeI. Treatment of [PtR2(dppma-PP′)] with HCl gives [Pt Cl (R) (dppma-PP′)] for R─C6H2Me3-2,4,6, C6H4-CH3-2, C6H4-Me-4, Me, 1-naphthyl. The 1H, 31P NMR parameters for these complexes are discussed. Attempted preparation of complexes of the type [PtR2 (dppma-P)2M] (R─C6H4-Me-2, Me CN-C6H4-Me-4); M─Pd, Pt, Au,) are reported. 相似文献
132.
Abd El-Badih A. G. Ghattas Hassan M. Moustafa Elsayed A. A. Hassanein Bahgat R. M. Hussein 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):1469-1481
Abstract Alkylation of 4-anilino-5-phenyl-4H-1,2,4-triazole-3-thiol (1) with some halo compounds yielded the corresponding sulfides 2a–f. Some sulfides 2e,f were cyclized to give triazolothiadiazines 3 and 4. Triazolothiadiazoles 5 and 6 were prepared through the reaction of compound 1 with carbon disulfide or ethyl orthoformate, respectively. Treatment of compound 1 with ethyl chloroformate or phenyl isothiocyanate yielded triazolo-thiadiazole and triazole 9 and 10, respectively. Reaction of compound 1 with Lawesson's reagent gave triazolothiadiazaphosphole derivative 11. Also, compound 1 underwent cyclocondensation reactions with some bidentate reagents to give triazolothiazines 4, 12, and 13. Triazolo-thiazepines and triaziepine 14–16 were synthesized via the reaction of compound 1 with β-ketoesters or ethyl cyanoacetate. Tricyclic systems 19 and 20 were prepared through the reaction of compound 4 with the appropriate reagent. Some synthesized compounds were tested for antibacterial activity. 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
133.
Abdolkarim Zare Alireza Hasaninejad Mohammad Hassan Beyzavi Ahmad Reza Moosavi-Zare Ali Khalafi-Nezhad Mehrnoosh Roshankar 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1702-1712
KF/Al 2 O 3 efficiently catalyzes the microwave-assisted Michael addition of sulfonamides to α,β-unsaturated esters under solvent-free conditions to afford N-alkyl derivatives of sulfonamides as biologically interesting compounds in high yields and in short reaction times. In this reaction, N,N-dialkylsulfonamides are also produced, but in very low yields. 相似文献
134.
Kh. M. Hassan A. M. Kamal El-Dean M. S. K. Youssef F. M. Atta M. S. Abbady 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):283-289
Abstract Thienopyridine oxazinone (1) has been prepared and explored as a precursor by its reaction with some reagents namely, ammonium acetate, aliphatic amines, aromatic amines, hydrazine hydrate, thiosemicarbazide, and ethyl glycinate to give pyridothienopyrimidines (11-VII). The pyrimidinone compound (11) was converted to the 4-chloro derivative (X) by its reaction with excess POCl3 Interaction of the 4-chlorocompound (X) with some reagents namely, hydrazine hydrate, methyl amine, aniline, sodium thiophenolate, ethyl glycinate, thiosemicarbazide and thiourea, yielded pyridothieno-pyrimidine derivatives (XI-XVII) substituted at 4-position, respectively. 相似文献
135.
Ali A. Abdel Hafez Ibrahim M. A. Awad Khairy M. Hassan 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):219-225
Abstract Some new derivatives containing both 8-hydroxyquinoline and sulphonylamino β-lactams and thiazolidinones have been prepared. These compounds were synthesized from the corresponding 8-hydroxyquinoline sulphonylhydrazide (1) by converting it to hydrazones (2). The latter hydrazones (2) were easily transformed to β-lactams (3) and thiazolidinones (4) by cyclocondensation reaction with chloroacetyl chloride and/or mercaptoacetic acid. Some metal chelates with Fe3+. Co2++, Ni2+, Cu2+ and Cd2+ have been prepared for some of the compounds and screened in vitro for their biological activity. 相似文献
136.
In this paper, new thermally stable isomeric unsubstituted polyesteramides have been successfully prepared by condensation of aromatic acids chlorides namely; isophthaloyl, pyridine-3,5-dicarbonyl and pyridine-2,6-pyridine-dicarbonyl dichlorides with the aminophenol isomers in NMP. Conducting the reaction in NMP/H2O (90/10 v/v) followed by centrifugal separation furnished the desired polymers as rod-like nanoparticles. The morphology of obtained nanoparticles were studied by SEM. Mixing NMP with H2O was essential for controlling the particles morphology and as a reaction accelerator. Pyridine-containing polymers exhibit semi-conducting nature as their conductivities increase with increasing temperature, while no variation of the conductivity with the temperature was observed for their corresponding phenylene analogues. Introduction of the nitro group into the polymer backbone led to a red shift in the absorption and the obtained polymers have a bright yellow color, which is unusual with this polymer group. Copper (II) ions were complexed the polyesteramides-containing nitro group in a (1:1) ratio. Complexes of pyridine-containing polymers exhibit semiconducting nature changed to metallic characters on heating and their conductivities increased tens of magnitudes than their corresponding ligands. These new types of polymeric materials and their nano-sized rods may have numerous applications in nanotechnology and their properties can be tuned for specific applications such as conducting adhesives and coating materials. 相似文献
137.
We aimed at preparing magnetic iron oxide particles by the oxidation-precipitation method in order to encapsulate these particles in polymer matrices composed of poly(acrylamide-styrene sulfonic acid sodium salt). Nanocomposites were synthesized by the incorporation of surface treated magnetic nanoparticles in the synthesized polymers via in situ inverse mini-emulsion polymerization process. The study parameter was the ionic monomer content in the synthesized polymers. The structure and the morphology of the magnetic nanogels were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), dynamic light scattering (DLS), thermal gravimetric analysis (TGA) and scanning electron microscopy (SEM). FTIR and XRD showed that pure magnetite was formed and successfully encapsulated in the composite nanoparticles. The polymer encapsulation could reduce the susceptibility to leaching and could protect the magnetite particle surfaces from oxidation. The ionic monomer content had a great effect on the magnetization behavior. Magnetite prepared by the oxidation precipitation method, of 50 nm mean particle size, was embedded successfully into the polymer nanogels with a reasonable magnetic response, as proved by vibrating sample magnetometer measurement. Magnetic nanocomposites were proven to be super-ferromagnetic materials. 相似文献
138.
Coordination polymers of 1,4-bis(2′-hydroxyphenylazomethine) phenylene have been prepared with the metal ions Ti(III), Cr(III), Fe(III), Mn(II), Ni(II), and Cu(II). They were characterized by elemental analysis, IR, and electronic spectra. The metal contents in all polymers were found to be consistent with a 1:1 (metal:ligand) stoichiometry. The thermal behavior of these coordination polymers has been studied by thermogravimetric analysis in air up to 750°C, and the data showed that they are thermally stable up to 200°C. Physical properties such as the solubility and viscosity of the polymer complexes were also determined. Electrical conductivity measurements of the synthesized polychelated polymers showed that they are insulators except for the Ni(II) complex which shows a semiconducting character. Mössbauer data clearly establish the 3 + oxidation state for the iron complex polymer. 相似文献
139.
Muhammad Raza Shah Mehdi Hassan Said Nadeem Muhammad Iqbal Bhanger 《Supramolecular chemistry》2013,25(10-12):777-782
A novel rhodium biphenylic imidazole phenanthroline metal-organic complex (BIP-MC) has been synthesised and characterised as a stable supramolecule. The structure of compound was established on the basis ESI, 1H NMR and UV–vis spectroscopic data. The selectivity of BIP-MC as a new fluorescent chemosensor for various antibiotics has been explored. The supramolecular interaction of amoxicillin with BIP-MC enhanced the fluorescence activity of BIP-MC. A linear response of the sensor was observed in the measuring ranges of excitation 240–298 nm and emission 290–360 nm with detection limits of up to 10 μg/ml at an optimum pH 8.0. Based on the observations made here, a new quantitative method for the determination of this drug in synthetic samples without the use of separation of matrix is developed. It is also inferred that the possible fluorescence enhancement is due to the formation of exciplex between the BIP-MC and amoxicillin. These finding will thus help in pharmacokinetics studies of drugs. The sensor was used for the direct assay of amoxicillin antibiotic in commercial pharmaceutical preparations. 相似文献
140.
Adnan J. Al-Rehaily Mohammad S. Ahmad Jamal Mustafa Mai M. Al-Oqail Wafaa H. Hassan Shabana I. Khan Ikhlas A. Khan 《Journal of Saudi Chemical Society》2013,17(1):67-76
Solanopubamine (3β-amino-5α, 22αH, 25βH-solanidan-23β-ol), a steroidal alkaloid was isolated from the alkaloidal fraction of Solanum schimperianum in significant yield. Its structure was established by IR, positive ESI-MS, 1D and 2D NMR. The presence of -3β-NH2 and -23β-OH groups was achieved through methylation, acetylation or coupling with octadecanoic and undec-11-enoic acids to produce six derivatives (2–7). Their structures were confirmed by spectroscopic analyses. Solanopubamine and semi-synthetic analogs are investigated for their in vitro cytotoxicity against a panel of human cancer cell lines and anti-microbial activity. Solanopubamine showed good antifungal activity only against Candida albicans and C. tenuis with MIC of 12.5 μg/mL. Semi-synthesized compounds (2–7) have failed to show anti-tumor and anti-microbial activities. 相似文献