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531.
Richa Gupta Ram Pal Chaudhary 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6):735-742
Abstract 8-Methoxy-4-phenyl-3,4,5,6-tetrahydrobenzo[h]quinazoline-2(1H)-thione, obtained by the condensation of 2-benzylidene-6-methoxy-3,4-dihydronapthalene-1(2H)-one with thiourea, on reaction with chloroacetic acid and 3-chloropropanoic acid in the presence of the ionic liquid N-methylpyridinium tosylate furnishes 3-methoxy-7-phenyl-7,10-dihydro-5H- benzo[h]thiazolo[2,3-b]quinazoline-9(6H)-one and 3-methoxy-7-phenyl-5,6,10,11-tetrahydro- benzo[h][1,3]thiazino[2,3-b]quinazoline-9(7H)-one. Further, condensation of the thione with 1,2-dibromoethane and 1,3-dibromopropane yields 3-methoxy-7-phenyl-6,7,9,10-tetrahydro-5 H-benzo[h]thiazolo[2,3-b]quinazoline and 3-methoxy-7-phenyl-5,6,7,9,10,11-hexahydrobenzo [h][1,3]thiazino[2,3-b]quinazoline respectively. Arylidene derivatives have been obtained by two routes. The structures of the cyclized compounds have been established on the basis of elemental analysis and spectroscopic data. The synthesized compounds were screened for antimicrobial activity. Some of the compounds showed promising antimicrobial activities. 相似文献
532.
Parigi Raghavendar Reddy Chithaluri Sudhakar Jayprakash Narayan Kumar Biswanath Das 《Helvetica chimica acta》2013,96(2):289-295
The first stereoselective total synthesis of the naturally occurring anti‐emetic diarylheptanoid (3R,5R)‐1‐(4‐hydroxyphenyl)‐7‐phenylheptane‐3,5‐diol ( 1 ) was accomplished starting from 4‐hydroxybenzaldehyde and involving a Sharpless kinetic resolution and an asymmetric epoxidation as the key steps (Scheme 2). The enantiomer 1a of this compound was also simultaneously prepared. 相似文献
533.
Sudhakar G.Patil Rahul R.Bagul Mangesh S.Swami Nandini Kotharkar Kalpana Darade 《中国化学快报》2011,22(8):883-886
A series of novel 5-benzylidene-3-(3-fluoro-4-yl-morpholin-4-yl-phenylimino)thiazolidin-4-one derivatives were synthesized using[bmIm]OH as a catalyst and were tested for their antibacterial and antifungal activities.These compounds showed moderate in vitro activities against the microorganisms tested. 相似文献
534.
Mehta P Kraslavsky V Bharti S Allakhverdiev SI Jajoo A 《Journal of photochemistry and photobiology. B, Biology》2011,104(1-2):308-313
In order to investigate changes in the heterogeneity of PSII, prompt fluorescence induction curves (PFIC) and delayed fluorescence induction curves (DFIC) were measured in wheat leaves after salt treatment. From these data, antenna heterogeneity and reducing side heterogeneity were estimated. Results show that antenna size, which is further differentiated into α, β and γ PSII centers, is changed under salt stress conditions. At higher salt concentration, there is a decrease in the number of α PSII centers with simultaneous increase in the amount of β and γ PSII centers. Another aspect of antenna heterogeneity is explained in terms of connectivity (or grouping) between PSII centers which did not change significantly under salt stress. Reducing side heterogeneity was assessed by both DFIC and PFIC and results show that a significant increase in the conversion of Q(B)-reducing centers to Q(B)-non-reducing centers is observed under salt stress. 相似文献
535.
536.
Summary: A new family of solution‐processable, photoluminescent, nanocomposite dendrimers based on cyclic phosphazene (CP) cores have been prepared and characterized. The synthetic approach is based on the preparation of bromoaromatic‐functionalized CP cores by reacting selected bromophenolic compounds with the commercially available hexachlorocyclotriphosphazene in yields >90%. The bromophenyl‐functionalized CP cores are then reacted with N‐p‐tolylpyren‐1‐amine using Buchwald‐Hartwig amination chemistry to give the dendrimers of interest in yields >90%. The resultant dendrimers have high glass transition (>165 °C) and decomposition temperatures (>465 °C), are monodisperse (PDI < 1.05), have high purity via common chromatographic techniques, have high photoluminescent quantum efficiencies (83%), and form defect‐free amorphous films via spin/dip coating. A comparison to their molecular analogues is also provided to demonstrate the superior properties of the new nanocomposite dendrimers.
537.
Avnesh Kumari Sudesh Kumar Yadav Yogesh B. Pakade Vineet Kumar Bikram Singh Abha Chaudhary Subhash Chandra Yadav 《Colloids and surfaces. B, Biointerfaces》2011,82(1):224-232
The plant isolated antioxidant quercitrin has been encapsulated on poly-d,l-lactide (PLA) nanoparticles by solvent evaporation method to improve the solubility, permeability and stability of this molecule. The size of quercitrin-PLA nanoparticles is 250 ± 68 nm whereas that PLA nanoparticles is 195 ± 55 nm. The encapsulation efficiency of nanoencapsulated quercitrin evaluated by HPLC and antioxidant assay is 40%. The in vitro release kinetics of quercitrin under physiological condition reveals initial burst release followed by sustained release. Less fluorescence quenching is observed with equimolar concentration of PLA encapsulated quercitrin than free quercitrin. The presence of quercitrin specific peaks on FTIR of five times washed quercitrin loaded PLA nanoparticles provides an extra evidence for the encapsulation of quercitrin into PLA nanoparticles. These properties of quercitrin nanomedicine provide a new potential for the use of such less useful highly active antioxidant molecule towards the development of better therapeutic for intestinal anti-inflammatory effect and nutraceutical compounds. 相似文献
538.
Single crystals of sodium nitrate have been purified and grown using zone-refining system fabricated in our laboratory. Laue photographs were employed to check the crystallinity. X-ray irradiated crystals have been studied by electron spin resonance. 相似文献
539.
S. K. Chaudhary 《Crystal Research and Technology》1994,29(7):995-998
Pure crystals of PbI2 have been grown using zone-refining system. The structural phase transition 12 R → 2 H has been observed when exposed to ruby laser light. The results have been explained on the basis of structural considerations of PbI2 and compared with the earlier existing findings in literature. 相似文献
540.
K. Sreelatha C. Venugopal S. K. Chaudhary N. V. Unnikrishnan 《Crystal Research and Technology》1999,34(7):897-900
Cadmium iodide has been studied from the point of view of nonlinear processes by experiments of optical amplification under two photon excitation. The two photon absorption (2PA) coefficient is determined by nonlinear transmittance technique. By means of two and three photon comparative luminescence measurements carried out using a ruby and neodymium laser, the three photon absorption (3PA) coefficient is determined. The experimental values of the absorption coefficients are compared with the predictions of the existing theories. 相似文献