Browsing Sciences – Articles de périodiques by Title
Now showing documents 1-20 of 32
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A Versatile cascade of intramolecular vilsmeier-haack and azomethine ylide 1,3-dipolar cycloaddition toward tricyclic cores of alkaloids
(2008)Abstract: In the pursuit of synthetic efficiency, we developed an innovative one-pot transformation of linear substrates into bi- and tricyclic adducts using a cascade of amide activation, nucleophilic cyclization, ... -
Addition of tethered nonaromatic carbon nucleophiles to chemoselectively activated amides
(2005)Abstract: In an effort to develop new ways of synthesizing polycyclic alkaloids, we successfully added silyl enol ethers, allylsilanes, and enamines to iminium ions generated from amides. Because of their higher oxidation ... -
Asymmetric total synthesis of (+)-virosine a via sequential nucleophilic cyclizations onto an activated formamide
(2012)Abstract: The first synthesis of tetracyclic alkaloid virosine A is reported. The natural alkaloid was prepared in only 13 steps, in an enantioenriched form. The azabicyclo[2.2.2]octane core was efficiently assembled using ... -
Bacillus subtilis and Bacillus velezensis population dynamic and quantification of spores after inoculation on ornamental plants
(2020)Abstract: Bacillus subtilis and Bacillus velezensis are used in organic agriculture as an alternative to chemical pesticides to fight against phytopathogen organisms. These Gram-positive soil-dwelling bacteria are able to ... -
Bis-michael acceptors as novel probes to study the Keap1/Nrf2/ARE pathway
Other titre : Supporting information for "Bis-michael acceptors as novel probes to study the Keap1/Nrf2/ARE pathway"(2016)Nuclear factor erythroid 2-related factor 2 (Nrf2) is a master regulator that promotes the transcription of cytoprotective genes in response to oxidative/electrophilic stress. Various Michael-type compounds were designed ... -
Comparative effects of adaptation on layer II-III and layer V-VI neurons in cat V1
(2016)Abstract: V1 is fundamentally grouped into columns that descend from layers II–III to V–VI. Neurons inherent to visual cortex are capable of adapting to changes in the incoming stimuli that drive the cortical plasticity. ... -
Competition between alkenes in intramolecular ketene-alkene [2 + 2] cycloaddition: What does it take to win?
(2005)Abstract: In the course of developing a new synthetic methodology using ketenes in sequential cycloaddition steps, we were faced with a competition problem with molecules containing a ketene tethered to more than one ... -
Crop scouting using UAV imagery : a case study for potatoes
(2020)Abstract : Crop scouting is essential to manage crops such as potatoes and detect stresses. In fact, conventional approaches require a lot of time and staff. The rise of unmanned aerial vehicle (UAV) imagery offers interesting ... -
Cyclic Di-GMP Riboswitch-Regulated Type IV Pili Contribute to Aggregation of Clostridium difficile
(2015)Clostridium difficile is an anaerobic Gram-positive bacterium that causes intestinal infections with symptoms ranging from mild diarrhea to fulminant colitis. Cyclic diguanosine monophosphate (c-di-GMP) is a bacterial ... -
DNA-damaging agents induce the RecA-independent homologous recombination functions of integrating conjugative elements of the SXT/R391 family
(2013)Abstract : Integrating conjugative elements (ICEs) of the SXT/R391 family are major contributors to the spread of antibiotic resistance genes. These elements also catalyze their own diversity by promoting inter-ICE ... -
Effect of substitution on the intramolecular 1,3-dipolar cycloaddition of alkene tethered münchnones
(2007)Abstract: A sequence of chemoselective activation of N-acylaminoacids, münchnone generation, intramolecular 1,3-dipolar cycloaddition, and ring opening efficiently generated functionalized polycyclic structures such as ... -
Electrophysiological and firing properties of neurons: categorizing soloists and choristers in primary visual cortex
(2015)Abstract: Visual processing in the cortex involves various aspects of neuronal properties such as morphological, electrophysiological and molecular. In particular, the neural firing pattern is an important indicator of ... -
Experimental evidence for spin-triplet states in Titanium implanted AlN film : an electron spin resonance study
(2023)Abstract : Spin carrying defects in wide-bandgap semiconductors are promising candidates for the development of quantum information and quantum sensing technology. Here we report experimental evidence for the formation of ... -
Functionalized polyhydroquinolines from amino acids using a key one-pot cyclization cascade and application to the synthesis of (±)-Δ7-mesembrenone
(2021)Substituted polyhydroquinolines are ubiquitous skeletal cores found in drugs and bioactive natural products. As a new route to access this motif, we successfully developed a one-pot cyclization cascade with high chemocontrol ... -
General approach toward aspidospermatan-type alkaloids using one-pot Vilsmeier–Haack cyclization and azomethine ylide cycloaddition
(2017)Abstract: The development of a new one-pot reaction sequence afforded the tricyclic core of several aspidospermatan-type alkaloids from a linear, densely functionalized substrate. The key sequence features a highly ... -
Highly chemoselective formation of aldehyde enamines under very mild reaction conditions
(2006)Abstract: Although ketone enamines are widely used in organic synthesis, aldehyde enamines are rarely employed due to the limitations of their preparation using known methods (need for acid or base, excess of amine, and/or ... -
Highly diastereoselective synthesis of substituted pyrrolidines using a sequence of azomethine ylide cycloaddition and nucleophilic cyclization
(2010)Abstract: Although cycloadditions of azomethine ylides usually give mixtures of endo/exo adducts, we successfully tuned the mechanistic path of a new reaction cascade to afford substituted pyrrolidines in high yields and ... -
Intramolecular additions of various π-nucleophiles to chemoselectively activated amides and application to the synthesis of (±)-tashiromine
(2006)Abstract: Vilsmeier-Haack type cyclizations proved to be particularly efficient for generating parts of the polycyclic cores of many alkaloids, although only monocyclizations have so far been reported. With the goal ... -
Light-induced valley polarization in interacting and nonlinear Weyl semimetals
(2017)It has been recently predicted that the interplay between Coulomb interactions and Berry curvature can produce interesting optical phenomena in topologically nontrivial two-dimensional insulators. Here, we present a theory ... -
Macrodynamics of economics: a bibliometric history
(2016)A history of specialties in economics since the late 1950s is constructed on the basis of a large corpus of documents from economics journals. The production of this history relies on a combination of algorithmic methods ...
