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971.
Wang K Patil AO Zushma S McConnachie JM 《Journal of inorganic biochemistry》2007,101(11-12):1883-1890
Nickel bis(dithiolene) complexes have been known for over four decades, yet little is known regarding the chemistry of this important subclass of inorganic coordination complexes in olefin oligomerization or polymerization. We report here that Ni(S(2)C(2)R(2))(2) (R=Ph, CF(3)) are converted to active catalysts for ethylene oligomerization when activated with methylaluminoxane (MAO). The catalyst activity is comparable to some nickel coordination complexes with N-donor ligands under similar conditions. The products are mainly butenes and hexenes, with small amounts of higher oligomers. The product distribution pattern is consistent with a nickel hydride species being the active center, where fast beta-hydride elimination limits the products to mostly butenes and hexenes. The exact nature of the active center and the reaction mechanism remain to be investigated. In addition, we determined the crystal structure for Ni[S(2)C(2)(CF(3))(2)](2). The molecule crystallizes in the P2(1)/n space group and adopts a planar geometry with expected bond lengths and angles. Comparing this structure with that for the donor-acceptor complex with perylene reveals elongation of both the Ni-S and the S-C bonds in the latter, suggesting reduction of Ni[S(2)C(2)(CF(3))(2)](2) may have occurred in the latter. 相似文献
972.
Background
Lipopolysaccharide (LPS) is a pathogen associated molecular pattern (PAMP) of animal and plant pathogenic bacteria. Variation at the interstrain level is common in LPS biosynthetic gene clusters of animal pathogenic bacteria. This variation has been proposed to play a role in evading the host immune system. Even though LPS is a modulator of plant defense responses, reports of interstrain variation in LPS gene clusters of plant pathogenic bacteria are rare. 相似文献973.
974.
Patil ST Higgs RE Brandt JE Knierman MD Gelfanova V Butler JP Downing AM Dorocke J Dean RA Potter WZ Michelson D Pan AX Jhee SS Hale JE 《Journal of proteome research》2007,6(3):955-966
Recognizing specific protein changes in response to drug administration in humans has the potential for significant utility in clinical research. In spite of this, many methodological and practical questions related to assessing such changes are unanswered. We conducted a series of clinical studies to assess the feasibility of measuring changes in proteins related to drug administration using a mass-spectrometry proteomics technique capable of quantifying hundreds of proteins simultaneously in cerebrospinal fluid (CSF) and plasma. Initially, the normal variability of proteins in these compartments was characterized in 16 healthy volunteers over a 2-week period. Drug-associated changes were subsequently assessed in the plasma and CSF proteomes of 11 subjects given atomoxetine, which served as a selective, centrally active probe to test the model. Protein levels in the CSF and plasma were unchanged between visits in the normal variability study. In contrast, statistically significant changes were detected in the CSF protein pattern after drug treatment. These studies suggest that identification of changes in the CSF proteome associated with the administration of centrally active drugs is feasible, and may be of value in the development of new drugs, as well as broader clinical research. 相似文献
975.
Agarwal Akanksha Patil Smita Gharat Krushna Pandit Reena A. Lali Arvind M. 《Photosynthesis research》2019,139(1-3):553-567
Photosynthesis Research - This study is the first to explore the influence of incident light intensity on the photosynthetic responses under mixotrophic growth of microalga Asteracys sp. When grown... 相似文献
976.
Firoz A. Kalam Khan Rashmi N. Kaduskar Rajesh Patil Rajendra H. Patil Siddique Akber Ansari Hamad M. Alkahtani Abdulrahman A. Almehizia Devanand B. Shinde Jaiprakash N. Sangshetti 《Bioorganic & medicinal chemistry letters》2019,29(4):623-630
In the present investigation, new chloroquinoline derivatives bearing vinyl benzylidene aniline substituents at 2nd position were synthesized and screed for biofilm inhibitory, antifungal and antibacterial activity. The result of biofilm inhibition of C. albicans suggested that compounds 5j (IC50 value?=?51.2?μM) and 5a (IC50 value?=?66.2?μM) possess promising antibiofilm inhibition when compared with the standard antifungal drug fluconazole (IC50?=?40.0?μM). Two compounds 5a (MIC?=?94.2?μg/mL) and 5f (MIC?=?98.8?μg/mL) also exhibited good antifungal activity comparable to standard drug fluconazole (MIC?=?50.0?μg/mL). The antibacterial screening against four strains of bacteria viz. E. coli, P. aeruginosa, B. subtilis, and S. aureus suggested their potential antibacterial activity and especially all the compounds except 5g were found more active than the standard drug ciprofloxacin against B. subtilis. To further gain insights into the possible mechanism of these compounds in biofilm inhibition through the agglutinin like protein (Als), molecular docking and molecular dynamics simulation studies were carried out. Molecular modeling studies suggested the clear role in inhibition of this protein and the resulting biofilm inhibitory activity. 相似文献
977.
Jaiprakash Sangshetti Shahebaaz K. Pathan Rajesh Patil Siddique Akber Ansari Santosh Chhajed Rohidas Arote Devanand B. Shinde 《Bioorganic & medicinal chemistry》2019,27(18):3979-3997
Phthalazine, a structurally and pharmacologically versatile nitrogen-containing heterocycle, has gained more attention from medicinal chemists in the design and synthesis of novel drugs owing to its pharmacological potential. In particular, phthalazine scaffold appeared as a pharmacophoric feature numerous drugs exhibiting pharmacological activities, in particular, antidiabetic, anticancer, antihypertensive, antithrombotic, anti-inflammatory, analgesic, antidepressant and antimicrobial activities. This review presents a summary of updated and detailed information on phthalazine as illustrated in both patented and non-patented literature. The reported literature have described the optimal pharmacological characteristics of phthalazine derivatives and highlighted the applicability of phthalazine, as potent scaffold in drug discovery. 相似文献
978.
979.
In this article, we present a graph theoretic method to visualize and analyze the system behavior under different operating conditions. The system attributes (or variables) are the nodes in the graphs, and partial correlation between a pair of attributes defines the distance between corresponding nodes, resulting in a fully connected graph. Then, the redundant links are reduced using Pathfinder Network Scaling technique to uncover the latent network structure. We use a simulated biological reactor dataset in normal and faulty operation to validate our method. The method is general and can be used to analyze several different systems. 相似文献
980.