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61.
A 2D polymer with Ag?C interactions, [Ag(μ5-TS)]n (1) [TS− = toluene-4-sulfonate], has been synthesized and characterized and its structure was determined by X-ray crystallography. In addition to coordination of the O atoms of TS−, the Ag atoms also form weak η1 Ag?C interactions. The thermal stability of 1 was studied by thermal gravimetric (TG) and differential thermal analyses (DTA). The ligand and compound 1 are luminescent in DMF, with emission maxima at 358 and 335, respectively. Solution studies of complex 1 were done in DMF and in CH3CN. 相似文献
62.
Shahnaz Rostamizadeh Nasrin Shadjou Ali Mohammad Amani Saeed Balalaie 《中国化学快报》2008,19(10):1151-1155
A simple and efficient procedure for the preparation of aryl- 14-H-dibenzo [aj]xanthenes by a one-pot condensation reaction of 2-naphthol and aryl aldehydes, in the presence of silica supported sodium hydrogen sulfate (NaHSO4/SiO2) as a catalyst and in the absence of solvent has been developed. The present method offers several advantages such as excellent yields, short reaction time (10-30min), mild condition, simple work-up, and the use of a cheap and environmentally friendly catalyst with remarkable reusability. 相似文献
63.
Summary A general method was used to prepare an array of unsymmetric sulfamides. This was accomplished by the stepwise addition of
CSI to tert-butanol followed by the addition of amines. To increase diversity, nitrogen group of Boc-sulfamides was alkylated with alcohols
using Mitsunobu reaction and Boc-group was removed using Si-TsOH. Microwave heating was used in all the steps. The final sulfamides
were released from Si-TsOH using NH3 in MeOH. 相似文献
64.
65.
Kha KM Perveen S Ayattollahi SA Saba N Rashid A Firdous S Haider SM Ullah Z Rahat S Khan Z 《Natural product letters》2002,16(4):283-290
Three glycosides and a long chain alcohol were isolated from the bulbs of Polianthes tuberosa, these were identified as 3,29-dihydroxystigmast-5-ene-3-O-beta-D-galactopyranoside (1), ethyl beta-D-galactopyranoside (2), ethyl-alpha-D-galactopyranoside (3), and 1-tricosanol (4). The structures were determined by extensive spectroscopic and chemical methods. All four isolated compounds were screened for their cytotoxicity, antibacterial and antifungal activities, none of the compounds showed any significant activity. 相似文献
66.
Shahnaz Rostamizadeh Masoomeh Nojavan Reza Aryan Elyass Isapoor 《Helvetica chimica acta》2013,96(12):2267-2275
An efficient one‐pot procedure for the synthesis of 3‐amino‐6‐aryl‐2‐phenylpyrazolo[3,4‐d]pyrimidine derivatives, through the reaction of aldehydes, malononitrile, benzamidine hydrochloride, and hydrazine hydrate in the presence of basic alumina‐supported sodium acetate (AcONa/Al2O3) under reflux conditions, is reported. This protocol has some advantages, including the use of a simple and one‐pot synthetic approach to attain pyrazolo[3,4‐d]pyrimidine directly from four readily available starting materials, simple workup, high overall yields of the products, and the simultaneous conversion of a NO2 to an amino group, offering an opportunity to synthesize more complex structures. 相似文献
67.
68.
Tour Jan Raiha Qadri Beena Naqvi Achyut Adhikari Said Nadeem Akhtar Muhammad 《Natural product research》2018,32(7):749-754
A novel compound Salvialactomine (1) along with two other unusual occurring natural products Pentatriacontanoic acid 1, 3-dihydroxypropyl ester (2) and 5-Methylflavone (3) were isolated from the callus of Salvia santolinifolia Boiss. Callus was initiated on MS medium containing NAA (0.5 mg/L) and further sub-cultured on MS medium supplemented with NAA with BA (0.5 + 1.5 mg/L). The structures of isolated compounds were determined by using mass spectrometry, 1D, and 2D–NMR techniques. Compounds 1, and 3 were tested for two different cancer cell lines, i.e. Hela (Cervical cancer cell) and PC-3 (Prostate cancer cells). IC50 was found as > 30 using Doxorobicin (0.912 ± 0.12 μmol L?1) as a standard. 相似文献
69.
Khan KM Saify ZS Begum S Noor F Khan MZ Hayat S Choudhary MI Perveen S Atta-Ur-Rahman Zia-Ullah 《Natural product research》2003,17(2):115-125
7-Hydroxy-4-methyl-2H-chromen-2-one (2), 7-hydroxy-4,5-dimethyl-2H-chromen-2-one (15) and their some derivatives were synthesized for exploring selected biological screening. The compounds 9 and 13 had shown high degree of cytotoxic activity. Three compound 9, 10 and 13 showed high degree of bactericidal activity amongst the present series. 相似文献
70.
W.J. Kim W. Chang S.B. Qadri J.M. Pond S.W. Kirchoefer J.S. Horwitz D.B. Chrisey 《Applied Physics A: Materials Science & Processing》2000,70(3):313-316
The relationship between the structure and the microwave dielectric properties of epitaxial Ba0.5Sr0.5TiO3 (BST) films has been investigated. Single-phase BST films (40-160 nm) have been deposited onto (100) MgO substrates by pulsed laser deposition. As-deposited films show a significant tetragonal distortion. The in-plane lattice parameters (a) are always larger than the surface normal lattice parameters (c). The tetragonal distortion depends on the thickness of the films and the post-deposition annealing conditions. Films annealed at 900 °C show less tetragonal distortion than the as-deposited film and the films annealed at higher temperatures. The distortion in the film is due to stress caused by the lattice mismatch and thermal expansion coefficient differences between the film and the substrate. The dielectric constant and its change with dc bias voltage of BST films on MgO at microwave frequencies increase with increasing annealing temperature from 900 °C to 1200 °C, which corresponds to an increase in the tetragonal distortion. 相似文献