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排序方式: 共有235条查询结果,搜索用时 156 毫秒
1.
Kumar Umesh Santu Kaity Banerjee Aparna Arya A. 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(9):3505-3516
Journal of Radioanalytical and Nuclear Chemistry - Literature studies reveal apaucity of data on the Th-Zr system. Investigations on the Th-30Zr alloy and its synthesis, microstructure and... 相似文献
2.
Aparna L. Joshi Pratiksha H. Roham Rooth Mhaske Mahadev Jadhav Kavitha Krishnadas Amol Kharat 《Natural product research》2015,29(23):2261-2264
Calotropis procera (family: Asclepiadaceae) contains cardiac glycosides which are cytotoxic to cancer cells. The extracts of C. procera have been reported to be cytotoxic to many cancer cell lines and this is the first report against the human skin melanoma cells (SK-MEL-2). The SK-MEL-2 cells treated with C. procera methanolic extract (CPME) were analysed for growth inhibition and apoptosis. The exposure of phosphatidylserine in apoptotic SK-MEL-2 was analysed by using the Annexin-V FITC flow cytometry method. In CPME-treated SK-MEL-2 cells, 19.6% of apoptotic and 58.3% dead cells were observed. The 15.97% and 15.85% of early apoptotic cells were found at 20 μg/mL of the ouabain and paclitaxel, respectively. Active caspases, nuclear degradation confirmed apoptotic SK-MEL-2 cells in time- and dose-dependent manner. The cell cycle analysis shows that CPME treated cells halt at G2/M phase. Significant cytotoxic activity of CPME against SK-MEL-2 may be attributed to its high cardenolide content. 相似文献
3.
Herein we describe an efficient one pot strategy toward highly functionalized isoquinolone fused azabicycles having great synthetic potential via C–H activation of N-pivaloyloxy benzamides under very mild conditions. The reaction is accomplished at room temperature within one hour in good to excellent yields and is found to be compatible with a range of diazabicyclic olefins and benzamides. The present strategy offers an easy route for the synthesis of biologically relevant compounds which possess multiple points for divergent synthesis. N–N bond cleavage of synthesized compounds may enable their significant role as effective precursors for the preparation of diaminocyclopentane fused isoquinolones. 相似文献
4.
Single‐step oxidative homocoupling of aryl Grignard reagents via Co(II), Ni(II) and Cu(II) Complexes under air 下载免费PDF全文
A simple catalytic system of direct synthesis for the symmetrical biaryls using catalytic amounts of Co(II), Ni(II) and Cu(II) complexes has been developed. The reaction system involves in situ synthesis of Grignard reagents. The complexes, containing bidentate Schiff base and dmit (2‐thioxo‐1,3‐dithiole‐4,5‐dithiolate) ligands, were compatible with diverse functionalities and afford a high yield of biaryls in a single step, proving to be promising catalysts in homocoupling reactions. Atmospheric oxygen is used as an oxidant which renders a green, simple and economical catalytic route. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
5.
Abstract On radiolysis tris(acetylacetonato) cobalt(III) in aqueous solutions is found to get reduced by reaction with (1) hydrated electrons, (2) H atoms, (3) OH radicals and (4) C2H2OH radicals. The bimolecular rate constants for the first three reactions, determined by competition kinetics are: 4 × 1010, 2.3 × 109 and 4.7 × 109 M?1sec?1 respectively. Absorption spectra of the irradiated solutions indicate the formation of bis(acetylacetonato) cobalt(II) from reaction (1), but not from (3). The total cobaltous yield in air-free solutions is given byG(Co++) = 5.6 and 6.5 at pH 6.5 and 1 respectively. It appears that Geaq- ∽ H + GoH ∽ 2.8 in neutral solutions. Considerations of material balance for the primary yields of radiolysis of water suggest the possibility that the so-called independent H-atoms in neutral solutions are probably excited water molecules or ion-pairs. 相似文献
6.
Anutosh Paria S. S. Greeshma Aparna Chaudhari M. Makesh C. S. Purushothaman K. V. Rajendran 《Applied biochemistry and biotechnology》2013,169(1):281-289
RNA interference-mediated silencing is an effective way of controlling white spot syndrome virus (WSSV). However, the effect of RNAi on the innate immune mechanism is not well understood. Prophenoloxidase (proPO) is an important component of the shrimp innate immunity. In the present study, nonspecific effect of two double-stranded (ds)RNA-expressing constructs, one targeting vp28 gene of WSSV (pCMV-VP28-LH) and another targeting green fluorescent protein (GFP) (pCMV-GFP-LH) on proPO2 gene expression, is investigated. mRNA expression levels of proPO2 in hemocytes of DNA construct-injected shrimp were estimated using real-time PCR with elongation factor 1-α as internal control. Empty vector (pcDNA)-injected shrimp were used as experimental control. In pCMV-VP28-LH-injected shrimp, proPO2 showed significant upregulation until 48 h post-injection (p.i.). Similarly, pCMV-GFP-LH-injected animals showed high levels of expression until 72 h p.i. WSSV-challenged animals, compared to pcDNA-injected control group, showed no significant change in expression of the gene until 24 h. However, an increased expression was noticed at 48 h p.i. Our results suggest that neither the plasmids nor the long hairpin RNA expressed by the constructs has any nonspecific silencing effect on the proPO2 expression. On the contrary, the consistent upregulation of proPO2 observed in shrimp injected with dsRNA at early time-points indicates the possibility of nonspecific protection against WSSV infection. 相似文献
7.
Aparna DeshpandeBrian J. LeRoy 《Physica E: Low-dimensional Systems and Nanostructures》2012,44(4):743-759
A material with novel fundamental properties that challenge our current understanding is always exciting for research. If the novel properties extend to the realm of device engineering and promise a revolution in applications, then the scope of its research knows no bounds. The story of graphene, the two dimensional form of carbon, has followed this path. Graphene has been the subject of numerous experimental and theoretical investigations since 2004 when an elegant and a simple technique to make monolayer graphene set the stage for extensive research. Many other techniques to make graphene were developed in parallel to this technique. As graphene is replete with unique structural and electronic properties scanning probe microscopy has proved to be an exciting and a rewarding venture. In this review we discuss the findings of scanning probe microscopy and how it has served as an indispensable tool to understand the properties of graphene and further graphene research. 相似文献
8.
Jyoti M. Madar Samundeeswari L. Shastri Megharaja Holiyachi Nirmala Naik Rashmi Kulkarni 《合成通讯》2018,48(4):375-386
Pursuing our recent interest regarding antimicrobial and anti-inflammatory activities of coumarin derivatives, we have synthesized a series of coumarin-linked pyridopyrimidinones by using Baylis Hillman adduct in aqueous condition with high purity. Pyrido[1,2-a]pyrimidin-2-ones are important class of heterocyclic compounds because of their use in medicinal and agro chemistry as active agents. All these newly synthesized compounds were evaluated for their antimicrobial and anti-inflammatory activity. Coumarin pyridopyrimidinones showed excellent anti-inflammatory activity against both MMP-2 and MMP-9 gelatinase zymography, whereas considerable good activity against Gram-positive and Gram-negative bacterial strains; however, antifungal activity observed in these series is more or less inactive. The active compounds of these series would be promising structural templates for the development of novel and more efficient anti-inflammatory agent. 相似文献
9.
10.
K. Shivashankar Manohar V. Kulkarni Lokesh A. Shastri Vijaykumar P. Rasal Sandur V. Rajendra 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):2187-2200
Various 4-aryloxymethylcoumarins have been obtained by the r.t. allylic substitution with formylphenols. These have been further reacted with o-aminothiophenol resulting in the formation of a benzothiazole skeleton. These compounds have been synthesised with a view to study their potential as microbial growth inhibitors. Comparative studies on the spectral and antimicrobial activities have also been carried out. 相似文献