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41.
Enantioselective Access to 1H‐Isoindoles with Quaternary Stereogenic Centers by Palladium(0)‐Catalyzed C−H Functionalization 下载免费PDF全文
Daria Grosheva Prof. Dr. Nicolai Cramer 《Angewandte Chemie (International ed. in English)》2018,57(41):13644-13647
A catalytic enantioselective method for the synthesis of chiral 1H‐isoindoles bearing quaternary stereogenic centers is reported. Powered by readily accessible phosphordiamidite ligands, the presented palladium(0)‐catalyzed C?H functionalization uses trifluoroacetimidoyl chlorides as electrophilic components. It delivers previously inaccessible perfluoroalkylated 1H‐isoindoles in high yields and enantioselectivities. The subsequent diastereoselective addition of nucleophiles provides access to densely substituted and sterically hindered isoindolines. 相似文献
42.
Đurđica Kovačić Davor Kralik Daria Jovičić Slavko Rupčić Brigita Popović Marina Tišma 《Applied biochemistry and biotechnology》2018,184(2):471-483
Several batch experiments were conducted on the anaerobic co-digestion of dairy cow manure (DCM) with three harvest residues (HR) (soybean straw, sunflower stalks, and corn stover). The influence of thermal pretreatment of HR on biogas production was investigated, where the HR were thermally pretreated at two different temperatures: T = 121 °C and T = 175 °C, during t = 30 and t = 90 min, respectively. All anaerobic co-digestion batch experiments were performed simultaneously under thermophilic regime, at T = 55 °C. Biogas and methane yields were significantly improved in experiments performed with corn stover thermally pretreated at 175 °C for 30 min (491.37 cm3/g VS and 306.96 cm3/g VS, respectively), if compared to experiments performed with untreated corn stover. The highest VS and COD removal rates were also observed in the same group of experiments and were 34.5 and 50.1%, respectively. The highest biogas and methane yields with soybean straw (418.93 cm3/g VS and 261.44 cm3/g VS, respectively) were obtained when soybean straw pretreated at 121 °C during 90 min. The highest biogas and methane yields with sunflower stalk (393.28 cm3/g VS and 245.02 cm3/g VS, respectively) were obtained when sunflower stalk was pretreated at 121 °C during 90 min. 相似文献
43.
Daria Goldmann Barbara Zdrazil Daniela Digles Gerhard F. Ecker 《Journal of computer-aided molecular design》2017,31(3):319-328
With the public availability of large data sources such as ChEMBLdb and the Open PHACTS Discovery Platform, retrieval of data sets for certain protein targets of interest with consistent assay conditions is no longer a time consuming process. Especially the use of workflow engines such as KNIME or Pipeline Pilot allows complex queries and enables to simultaneously search for several targets. Data can then directly be used as input to various ligand- and structure-based studies. In this contribution, using in-house projects on P-gp inhibition, transporter selectivity, and TRPV1 modulation we outline how the incorporation of linked life science data in the daily execution of projects allowed to expand our approaches from conventional Hansch analysis to complex, integrated multilayer models. 相似文献
44.
Godofredo Bautista Giovanni Tapang Vincent Ricardo Daria 《Optics Communications》2009,282(18):3746-25899
We report parallel two-photon photopolymerization of microgear patterns by exposing a photoresist to holographically generated optical vortices. The optical vortices are created by imparting a helical pitch onto the incident light using a programmable lithographic phase mask realized with a computer addressable phase-only spatial light modulator. By varying the phase levels of the spatial light modulator, the truncated helical phase of an optical vortex results in output intensity patterns that typifies that of microgears instead of perfect doughnut beams. Our experiments and simulations are in good agreement implying a more efficient and highly parallel two-photon photopolymerization scheme that can be subsequently used for non-scanning fabrication of microgears. 相似文献
45.
E. M. Popov G. M. Lipkind V. Z. Pletnev S. F. Arkhipova 《Chemistry of Natural Compounds》1973,7(2):175-181
Summary 1. The form of the potential surface of the methyl esters of -acetylamino acids and of the methylamides of -acetoxy acids is sensitive to the geometry of the side chain and to the presence of N-methyl groups in the main chain.2. The conformational states of the molecules considered are described by a limited number of canonical forms: R, B, L, and P.3. With respect to the interaction of the atoms of the main chain, the ester group is stereochemically equal to the amide group. The difference between these groups consists in small differences in interactions with the atoms of the side chains.M. M. Shemyakin Institute of the Chemistry of Natural Compounds, Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 184–191, March, 1971. 相似文献
46.
A. A. Arkhipova 《Journal of Mathematical Sciences》2000,101(5):3385-3397
Quasilinear nondiagonal parabolic systems with quadratic growth in the gradient in a parabolic cylinder Q are considered. Under Dirichlet and Neumann boundary conditions, a partial Hölder continuity of solutions u∈W 2 t,1 (Q)~L∞ (Q) up to the lateral surface of Q is proved.The Hausdorff dimension of a singular set is estimated. In the proof, we get rid of the maximum principle theorem for respective model linear problems. Bibliography: 21 titles. 相似文献
47.
Magorzata Szultka-Myska Daria Janiszewska Pawe Pomastowski Micha Zoch Wojciech Kupczyk Bogusaw Buszewski 《Molecules (Basel, Switzerland)》2021,26(16)
The bacterial infection of post-operative wounds is a common health problem. Therefore, it is important to investigate fast and accurate methods of identifying bacteria in clinical samples. The aim of the study was to analyse the use of the MALDI-TOF MS technique to identify microorganism wounds that are difficult to heal. The most common bacteria are Escherichia coli, Staphylococcus spp., and Enterococcus spp. We also demonstrate the effect of culture conditions, such as the used growth medium (solid: Brain Heart Infusion Agar, Mueller Hilton Agar, Glucose Bromocresol Purple Agar, and Vancomycin Resistance Enterococci Agar Base and liquid: Tryptic Soy Broth and BACTEC Lytic/10 Anaerobic/F), the incubation time (4, 6, and 24h), and the method of the preparation of bacterial protein extracts (the standard method based on the Bruker guideline, the Sepsityper method) to identify factors and the quality of the obtained mass spectra. By comparing the protein profiles of bacteria from patients not treated with antibiotics to those treated with antibiotics based on the presence/absence of specific signals and using the UniProt platform, it was possible to predict the probable mechanism of the action of the antibiotic used and the mechanism of drug resistance. 相似文献
48.
We investigate the stability of some inequalities of isoperimetric type related to Monge–Ampère functionals. In particular, firstly we prove the stability of a reverse Faber–Krahn inequality for the Monge–Ampère eigenvalue and its generalization. Then we give a stability result for the Brunn–Minkowski inequality and for a consequent Urysohn’s type inequality for the so-called \(n\) -torsional rigidity, a natural extension of the usual torsional rigidity. 相似文献
49.
Daria A. Smirnova Ilya V. Shadrivov Alexander I. Smirnov Yuri S. Kivshar 《Laser \u0026amp; Photonics Reviews》2014,8(2):291-296
Nonlinear properties of a multi‐layer stack of graphene sheets are studied. It is predicted that such a structure may support dissipative plasmon‐solitons generated and supported by an external laser radiation. Novel nonlinear equations describing spatial dynamics of the nonlinear plasmons driven by a plane wave in the Otto configuration are derived and the existence of single and multi‐hump dissipative solitons in the graphene structure is predicted. 相似文献
50.