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71.
CH Oxidation of Ingenanes Enables Potent and Selective Protein Kinase C Isoform Activation 下载免费PDF全文
Dr. Yehua Jin Dr. Chien‐Hung Yeh Dr. Christian A. Kuttruff Dr. Lars Jørgensen Dr. Georg Dünstl Dr. Jakob Felding Dr. Swaminathan R. Natarajan Prof. Dr. Phil S. Baran 《Angewandte Chemie (International ed. in English)》2015,54(47):14044-14048
Ingenol derivatives with varying degrees of oxidation were prepared by two‐phase terpene synthesis. This strategy has allowed access to analogues that cannot be prepared by semisynthesis from natural ingenol. Complex ingenanes resulting from divergent C? H oxidation of a common intermediate were found to interact with protein kinase C in a manner that correlates well with the oxidation state of the ingenane core. Even though previous work on ingenanes has suggested a strong correlation between potential to activate PKCδ and induction of neutrophil oxidative burst, the current study shows that the potential to activate PKCβII is of key importance while interaction with PKCδ is dispensable. Thus, key modifications of the ingenane core allowed PKC isoform selectivity wherein PKCδ‐driven activation of keratinocytes is strongly reduced or even absent while PKCβII‐driven activation of neutrophils is retained. 相似文献
72.
Shekhar Kumar U. Kamachi Mudali R. Natarajan 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(3):717-720
Conventionally composition of the actinide-extractant solvate is assumed to be the same in the unpartitioned organic phase
and the formed third phase. For example, if a m:n solvate has formed during extraction, the solvate is expected to be in the
same state even during the third phase condition. However contemporary analysis, based on the spectroscopy measurements and
empirical observations, has indicated the presence of an extended solvate. In this article, the proposed speciation in nitric
acid and U(VI) third phase formation in n–n dialkyl amide/dodecane-nitric acid systems has been modeled with empirical correlations. 相似文献
73.
D. Arocikia Jency R. Parimaladevi G. Vasant Sathe Mahalingam Umadevi 《Journal of Cluster Science》2018,29(2):281-287
Polychlorinated biphenyls (PCBs) are harmful even at trace level in the environment, and they are difficult to detect. This work presents a simple method for preparation of glutathione (GSH) functionalized gold nanoparticles (Au NPs) (GSH-Au NPs) for the detection of PCBs and its isomers based on surface enhanced Raman scattering (SERS). The prepared Au NPs show the surface plasmon band around 533 nm. The crystallinity and formation of GSH-Au NPs were confirmed by using X-ray diffraction and vibrational studies. Transmission electron microscopic analysis showed the average particle size of GSH-Au NPs is around 16 nm. The morphology of the GSH-Au NPs indicates dumbbell-shaped structures with “hot spots” present. These hot spots increase the SERS activity significantly. Gas chromatography–mass spectrum showed that the soil extract contained PCBs, which, has also been detected using SERS. SERS based detection is simple and powerful for identifying the PCBs, as established here for PCBs in the real soil sample.Hence, from this investigation, a rapid, sensitive, cost-effective sensing method for detecting toxic PCBs in the environment was demonstrated. 相似文献
74.
Vasant R Choudhary Chinta Sivadinarayana Kshudiram Mantri 《Journal of Chemical Sciences》1999,111(5):669-676
The acidity and initial and time-on-stream activity in propane aromatization (at 550°C, space velocity of 3100 cm3g−1
(zeolite)h−1) of Ga-impregnated H-ZSM-5 zeolite without or with binders (50 wt%), such as silica, alumina and kaolin, have been investigated.
Both the acidity and catalytic activity of the zeolite are influenced by the presence of binder in the catalyst, depending
upon the binder. The influence is found to be lowest for alumina and highest for kaolin. Among the binders, alumina is the
most preferred binder for the zeolite catalyst. 相似文献
75.
Natarajan Arumugam 《Tetrahedron》2010,66(4):969-975
Synthesis of novel pyrroloisoquinoline and indolizinoindole derivatives with β-lactam unit has been achieved by sequential intermolecular 1,3-dipolar cycloaddition reaction and Pictet-Spengler cyclization. The azomethine ylide derived from β-lactam imine of α-amino ester in the presence of silver acetate reacted with nitrostyrenes to give pyrrolidinyl β-lactam, which underwent Pictet-Spengler cyclization in presence of trifluoroacetic acid to give pyrroloisoquinolines and indolizinoindoles. 相似文献
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57Fe Mössbauer spectroscopy is used to study the interactions, geometry, and the coordination characteristics of the Fe-complexes of biopolymers such as chitosan, glucosamine, and chondritin sulfate. In addition, a computational effort is undertaken for predicting the geometries and energies of the metal complexes by the Density Functional Theory (DFT) methods as implemented in the Gaussian 2003 quantum mechanical program. Both experimental and computational results suggest that the structure of the metal complexes resemble closely the structure of the active sites of metalloenzymes in 2+ or 3+ oxidation states and is at least tetracoordinated and can possibly have six ligands. 相似文献
80.