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871.
Label-free biosensors based on direct optical detection principles are widely used in many different fields of research. Currently the higher level of automation and the increasing throughput of this technology are stimulating the interest of pharmaceutical companies. The information gained with label-free biosensors can be extremely valuable during the drug design process, particularly in combination with complementary techniques, including NMR, mass spectrometry and X-ray crystallography. In this article we focus on the advantages of direct optical biosensors especially in the field of fragment-based drug design, which is a widely used and extremely promising concept. Furthermore, we present optical biosensors as versatile tools for fragment-based screening and the future drug design process. 相似文献
872.
Stefano Favaro Igor Prünster Stephen G. Walker 《Methodology and Computing in Applied Probability》2012,14(2):253-262
In the present paper we introduce a generalization of the well–known Chu–Vandermonde identity. In particular, by inductive
reasoning, the identity is extended to a multivariate setup in terms of the fourth Lauricella function. The main interest
in such generalizations derives from the species diversity estimation and, in particular, prediction problems in Genomics
and Ecology within a Bayesian nonparametric framework. 相似文献
873.
Dennis Popp Dr. Sven M. Elbert Chantal Barwig Julian Petry Dr. Frank Rominger Prof. Dr. Michael Mastalerz 《Angewandte Chemie (International ed. in English)》2023,62(19):e202219277
The palladium catalyzed cyclotrimerization of ortho-silylaryl triflates as aryne precursors is meanwhile an established method to synthesize polycyclic aromatic hydrocarbons (PAHs) with triphenylene cores. During the palladium-catalyzed reaction of a pyrene with an o-silylaryl triflate moiety in the K-region higher homologues with central eight- and ten-membered rings (the pyrenylenes) were found, besides the expected trimer and a protocol was developed to isolate all members of this series. This unprecedented new class of PAHs was fully investigated by all means, including X-ray diffraction of single-crystals, UV/Vis and fluorescence spectroscopy and theoretical calculations. Supported by density-functional theory (DFT) calculations, a mechanism of all higher cyclooligomers is proposed. 相似文献
874.
875.
Hugo Amistadi-Revol Dr. Julian Garrec Dr. Nicolas Casaretto Dr. Sébastien Prévost 《European journal of organic chemistry》2023,26(24):e202300359
Herein, a regioselective bromination or chlorination reaction of 1-naphthaldehydes is described. Without additive, the palladium-catalyzed C−H halogenation showed a C8-regioselectivity, whereas the formation of an aromatic imine intermediate allowed a switch to a C2-reactivity. Mechanistic studies and DFT calculations were performed to explain the regioselectivity and the synthesized halogenated products were used as key building blocks to access polycyclic natural product skeletons. 相似文献
876.
Hugo Amistadi-Revol Shanshan Liu Dr. Sébastien Prévost 《European journal of organic chemistry》2023,26(31):e202300582
In order to directly functionalize C−H bonds of complex molecules and, in particular, to control the regioselectivity of the reaction, a wide range of directing groups has been used. However, these directing groups need to be installed and removed for further applications, which may limit the use of C−H activation in synthesis. Concerning aldehydes and ketones, a transient directing group strategy has recently emerged to overcome this drawback. The addition of an additive, in general an amine, allowed the in situ formation of the real directing group to achieve C−H activation. This review presents the latest developments in the field over the period 2020–2023. 相似文献
877.
Marília Caroline C. de Sá Teresa Córdova Príamo Albuquerque Melo Jr. Ramón Díaz de León José Carlos Pinto 《大分子反应工程》2023,17(1):2200041
The present work presents phenomenological models to describe the coordination polymerization of β-myrcene using the Ziegler–Natta catalyst system composed by neodymium versatate (NdV3), diisobutylaluminum hydride (DIBAH), and dimethyldichlorosilane. The kinetic parameters required to simulate the reactions are estimated, and the amount of DIBAH used as a chain transfer agent (CTA) is obtained by a data reconciliation strategy since it can participate in side reactions. Several experiments are performed at different conditions to evaluate the impact of key operation variables on the control of monomer conversion and average molar masses. It is shown that the initial NdV3, β-myrcene, and DIBAH concentrations exert strong influences on the course of the polymerization. The kinetic mechanism of Coordinative Chain Transfer Polymerization (CCTP) fits well with the data of final average molar masses and monomer conversion, while the dynamic trajectories of these variables are fitted better by kinetic mechanisms of more conventional coordination polymerizations, considering site deactivation and termination by chain transfer. In all cases, the proposed models are able to predict the experimental data well after successful parameter estimation and reconciliation of CTA concentrations, indicating that the kinetic mechanism can be characterized by different kinetic regimes. 相似文献
878.
Carsten E. Seyfert Christoph Porten Dr. Biao Yuan Selina Deckarm Dr. Fabian Panter Dr. Chantal D. Bader Janetta Coetzee Felix Deschner Dr. Kamaleddin H. M. E. Tehrani Prof. Dr. Paul G. Higgins Prof. Dr. Harald Seifert Prof. Dr. Thomas C. Marlovits Dr. Jennifer Herrmann Prof. Dr. Rolf Müller 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2023,135(2):e202214094
879.
M. Sc. Philipp Grewelinger B. Sc. Tim Wiesmeier Dr. Carsten Präsang Dr. Bernd Morgenstern Prof. Dr. David Scheschkewitz 《Angewandte Chemie (International ed. in English)》2023,62(40):e202308678
Diboriranides are the smallest conceivable monoanionic aromatic cycles, yet only limited examples have been reported and their reactivity and complexation behavior remain completely unexplored. We report a straightforward synthesis of the first peraryl diboriranide c-(DurB)2CPh− as its lithium salt in three steps via the corresponding non-classical diborirane from a readily available 1,2-dichlorodiborane(4) (Dur=2,3,5,6-tetramethylphenyl). With the preparation and complete characterization of representative complexes with tin, copper, gold and zinc, we demonstrate the strong preference of the diboriranide for σ-type coordination modes towards main group and transition metal centers under unperturbed retention of the three-membered B2C-ring's 2e− π-system. 相似文献
880.
Marianne E. Prévôt Senay Ustunel Guillaume Freychet Caitlyn R. Webb Mikhail Zhernenkov Ron Pindak Robert J. Clements Elda Hegmann 《Macromolecular bioscience》2023,23(3):2200343
Advanced manufacturing has received considerable attention as a tool for the fabrication of cell scaffolds however, finding ideal biocompatible and biodegradable materials that fit the correct parameters for 3D printing and guide cells to align remain a challenge. Herein, a photocrosslinkable smectic-A (Sm-A) liquid crystal elastomer (LCE) designed for 3D printing is presented, that promotes cell proliferation but most importantly induces cell anisotropy. The LCE-based bio-ink allows the 3D duplication of a highly complex brain structure generated from an animal model. Vascular tissue models are generated from fluorescently stained mouse tissue spatially imaged using confocal microscopy and subsequently processed to create a digital 3D model suitable for printing. The 3D structure is reproduced using a Digital Light Processing (DLP) stereolithography (SLA) desktop 3D printer. Synchrotron Small-Angle X-ray Diffraction (SAXD) data reveal a strong alignment of the LCE layering within the struts of the printed 3D scaffold. The resultant anisotropy of the LCE struts is then shown to direct cell growth. This study offers a simple approach to produce model tissues built within hours that promote cellular alignment. 相似文献