Preparation de quelques cyclohexène-2 diones-1,4 et de leurs dérivés

1971 ◽  
Vol 49 (21) ◽  
pp. 3515-3523 ◽  
Author(s):  
J. Y. Savoie ◽  
P. Brassard
Keyword(s):  
Coupling Constants ◽  
Osmic Acid ◽  
New Class ◽  
Acid Catalyzed ◽  
First Time ◽  
Catalyzed Oxidation

The osmic acid catalyzed oxidation of quinones has yielded for the first time to our knowledge the monomers of some cis-5,6-dihydroxycyclohex-2-ene-1,4-diones. Toluquinone and o-xyloquinone give mixtures of the two possible isomers. Observation of the n.m.r. spectra suggests that this new class of compounds are in general conformationally more mobile than quinonedihalides. The conversion of cyclohex-2-ene-1,4-diones into oximes allows the easy evaluation of all the important coupling constants.

Le dimère de la cis dihydroxy-5,6 cyclohexène-2 dione-1,4

1969 ◽  
Vol 47 (5) ◽  
pp. 733-737 ◽  
Author(s):  
J. Y. Savoie ◽  
P. Brassard
Keyword(s):  
Solid State ◽  
Sodium Chlorate ◽  
Osmic Acid ◽  
Acid Catalyzed ◽  
Catalyzed Oxidation

The osmic acid catalyzed oxidation of p-benzoquinone by sodium chlorate has long been recognized to yield a dimeric substance. By using progressively more vigorous conditions of acetylation, it has been possible to prepare from it three acetates corresponding to the dimer and to products of increasing degrees of dehydration and aromatization. The compounds have now been identified as the tetraacetates of 1,2,6,7-tetrahydroxydibenzo-p-dioxine (2a), of 2-oxo-1,4a (trans),6,7-tetrahydroxy-1,2,4a,10a-tetrahydrodibenzo-cis-p-dioxinne (3) and of the monohemiacetal dimer of cis-5,6-dihydroxycyclohex-2-ene-1,4-dione(4b). The structure of the dimer in the solid state and in solution is discussed.

scholarly journals The antimicrobial potential of cannabidiol

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Mark A. T. Blaskovich ◽  
Angela M. Kavanagh ◽  
Alysha G. Elliott ◽  
Bing Zhang ◽  
Soumya Ramu ◽  
...  
Keyword(s):  
Bacterial Infections ◽  
Modern Medicine ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
New Class ◽  
Clostridioides Difficile ◽  
Excellent Activity ◽  
Induce Resistance ◽  
First Time

AbstractAntimicrobial resistance threatens the viability of modern medicine, which is largely dependent on the successful prevention and treatment of bacterial infections. Unfortunately, there are few new therapeutics in the clinical pipeline, particularly for Gram-negative bacteria. We now present a detailed evaluation of the antimicrobial activity of cannabidiol, the main non-psychoactive component of cannabis. We confirm previous reports of Gram-positive activity and expand the breadth of pathogens tested, including highly resistant Staphylococcus aureus, Streptococcus pneumoniae, and Clostridioides difficile. Our results demonstrate that cannabidiol has excellent activity against biofilms, little propensity to induce resistance, and topical in vivo efficacy. Multiple mode-of-action studies point to membrane disruption as cannabidiol’s primary mechanism. More importantly, we now report for the first time that cannabidiol can selectively kill a subset of Gram-negative bacteria that includes the ‘urgent threat’ pathogen Neisseria gonorrhoeae. Structure-activity relationship studies demonstrate the potential to advance cannabidiol analogs as a much-needed new class of antibiotics.

scholarly journals Homopiperazine (Hexahydro-1,4-diazepine)

Molbank ◽  
10.3390/m1200 ◽  
2021 ◽  
Vol 2021 (2) ◽  
pp. M1200
Author(s):  
R. Alan Aitken ◽  
Dheirya K. Sonecha ◽  
Alexandra M. Z. Slawin
Keyword(s):  
13C Nmr ◽  
Title Compound ◽  
Coupling Constants ◽  
15N Nmr ◽  
Time Data ◽  
Nmr Spectrum ◽  
X Ray ◽  
First Time

The X-ray structure of the title compound has been determined for the first time. Data on its 1H–13C-NMR coupling constants and 15N-NMR spectrum are also given.

scholarly journals Phenotypic Susceptibility to Bevirimat in Isolates from HIV-1-Infected Patients without Prior Exposure to Bevirimat

2010 ◽  
Vol 54 (6) ◽  
pp. 2345-2353 ◽  
Author(s):  
Nicolas A. Margot ◽  
Craig S. Gibbs ◽  
Michael D. Miller
Keyword(s):  
Recombinant Viruses ◽  
Gag Polyprotein ◽  
New Class ◽  
Major Mutation ◽  
Hiv Drugs ◽  
The Impact ◽  
First Time ◽  
Hiv 1

ABSTRACT Bevirimat (BVM) is the first of a new class of anti-HIV drugs with a novel mode of action known as maturation inhibitors. BVM inhibits the last cleavage of the Gag polyprotein by HIV-1 protease, leading to the accumulation of the p25 capsid-small peptide 1 (SP1) intermediate and resulting in noninfectious HIV-1 virions. Early clinical studies of BVM showed that over 50% of the patients treated with BVM did not respond to treatment. We investigated the impact of prior antiretroviral (ARV) treatment and/or natural genetic diversity on BVM susceptibility by conducting in vitro phenotypic analyses of viruses made from patient samples. We generated 31 recombinant viruses containing the entire gag and protease genes from 31 plasma samples from HIV-1-infected patients with (n = 21) or without (n = 10) prior ARV experience. We found that 58% of the patient isolates tested had a >10-fold reduced susceptibility to BVM, regardless of the patient's ARV experience or the level of isolate resistance to protease inhibitors. Analysis of mutants with site-directed mutations confirmed the role of the V370A SP1 polymorphism (SP1-V7A) in resistance to BVM. Furthermore, we demonstrated for the first time that a capsid polymorphism, V362I (CA protein-V230I), is also a major mutation conferring resistance to BVM. In contrast, none of the previously defined resistance-conferring mutations in Gag selected in vitro (H358Y, L363M, L363F, A364V, A366V, or A366T) were found to occur among the viruses that we analyzed. Our results should be helpful in the design of diagnostics for prediction of the potential benefit of BVM treatment in HIV-1-infected patients.

Production and Technical Characteristics of a New Class of Amorphous Metals

1995 ◽  
Vol 400 ◽  
Author(s):  
R.T. Malkhassian
Keyword(s):  
Amorphous Phase ◽  
Quantum Chemical ◽  
New Technology ◽  
Chemical Technology ◽  
Quantum Level ◽  
Vibrationally Excited ◽  
New Class ◽  
The Third ◽  
Hydrogen Molecules ◽  
First Time

AbstractA new technology for obtainment of amorphous single-component metals is presented.For the first time the reduction of molybdenum oxide with formation of its amorphous phase is realized in conditions of a given quantum-chemical technology by means of vibrationally excited to the third quantum level hydrogen molecules with 1.5 ± 0.2 eV energy. The evidences of formation of this nonequilibrium amorphous phase are presented along with certain physicochemical properties of the obtained amorphous molybdenum.A model is proposed for the origin of amorphous phase under the influence of nonequilibrium quantum-chemical technology.

Brønsted Acid-Catalyzed Solvent-Controlled Regioselective Hydrothiolation and Diastereoselective Cascade Cyclization of Dienes

2021 ◽  
Author(s):  
Kai Ji ◽  
Ka Lu ◽  
Jie Huang ◽  
Zi-Hao Li ◽  
Tong-Mei Ding ◽  
...  
Keyword(s):  
Free Atom ◽  
Bronsted Acid ◽  
Brønsted Acid ◽  
Metal Free ◽  
Cascade Cyclization ◽  
Brönsted Acid ◽  
Acid Catalyzed ◽  
First Time

A highly regio- and diastereo-selective Brønsted acid-catalyzed tandem hydrothiolation/Friedel-Crafts reaction of linear 1,3-dienes has been developed for the first time, which provides a metal-free, atom-economic and concise way of constructing...

scholarly journals A NEW ACID CATALYZED OXIDATION OF SOME ACETYLENIC COMPOUNDS WITH SELENIUM DIOXIDE

1972 ◽  
Vol 1 (3) ◽  
pp. 229-232 ◽  
Author(s):  
Noboru Sonoda ◽  
Yuji Yamamoto ◽  
Shinji Murai ◽  
Shigeru Tsutsumi
Keyword(s):  
Selenium Dioxide ◽  
Acid Catalyzed ◽  
Catalyzed Oxidation ◽  
Acetylenic Compounds

Lewis acid-catalyzed tandem cyclization of in situ generated o-quinone methides and arylsulfonyl hydrazides for a one-pot entry to 3-sulfonylbenzofurans

2019 ◽  
Vol 6 (24) ◽  
pp. 3929-3933 ◽  
Author(s):  
Fan-Xiao Meng ◽  
Ruo-Nan Wang ◽  
Hong-Li Huang ◽  
Shu-Wen Gong ◽  
Qian-Li Li ◽  
...  
Keyword(s):  
Lewis Acid ◽  
Quinone Methides ◽  
One Pot ◽  
Acid Catalyzed ◽  
Tandem Cyclization ◽  
First Time

Lewis acid-mediated one-pot tandem cyclization of o-QMs with arylsulfonyl hydrazides was described for the first time and the corresponding 3-sulfonylbenzofuran products were obtained in moderate to good yields.

Graphite/UPE Nanocomposite: Transport, Thermal, Mechanical and Viscoelastic Properties

2019 ◽  
Vol 23 ◽  
pp. 201-212
Author(s):  
Shivkumari Panda ◽  
Dibakar Behera ◽  
Tapan Kumar Bastia
Keyword(s):  
Transport Properties ◽  
Unsaturated Polyester ◽  
Homogeneous Distribution ◽  
Thermo Gravimetric ◽  
New Class ◽  
The Matrix ◽  
Novel Method ◽  
Water Transport Properties ◽  
First Time

This chapter presents the preparation and characterization of some unique properties of nanocomposites by dispersing graphite flakes in commercial unsaturated polyester (UPE) matrix. The composite was prepared by a novel method with the use of solvent swelling technique. Three different specimens of UPE/graphite nanocomposites were fabricated with addition of 1, 2 and 3 wt% of graphite flakes. Except mechanical, viscoelastic and thermo gravimetric properties, transport properties like electrical conductivity, thermal conductivity and water transport properties were studied for the first time. Graphite flakes propose enhanced properties to the composites suggesting homogeneous distribution of the nanofiller in the matrix and strong interaction with the matrix. 2wt% nanofiller loading showed superior essential characteristics and after that the properties reduced may be due to the nucleating tendency of the nanofiller particles. The XRD pattern showed the compatibility of the graphite flakes by introducing a peak around 26.550 in the nanocomposites. SEM Properties are also in agreement with the compatibility. Nanocomposite with 2wt% graphite also showed remarkable enhancement in transport, mechanical, viscoelastic and thermo gravimetric properties. So by introduction of a small quantity of graphite endow the new class of multiphase nanocomposites with inimitable structure and tremendous application.

scholarly journals On the Use of a New Class of Simplified Multi-Window Iris Notch in the Design of Ultra-Compact High-Rejection Waveguide Filters for Satellite Links

Electronics ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 1221
Author(s):  
Juan Luis Cano ◽  
Angel Mediavilla ◽  
Antonio Tazon
Keyword(s):  
High Performance ◽  
Symmetry Plane ◽  
Pass Band ◽  
Transmission Zero ◽  
New Class ◽  
X Band ◽  
Waveguide Filters ◽  
Field Symmetry ◽  
Insertion Losses ◽  
First Time

This work introduces a simplified multi-aperture iris notch suitable for designing waveguide filters having an extremely improved compactness/rejection ratio, regarding available solutions, and adequate pass-band performances. The proposed iris architecture, analyzed for the first time, exhibits a unique transmission zero in the waveguide mono-mode bandwidth which can be easily located below or above the pass-band. The frequency of this transmission zero is evaluated in terms of the iris dimensions thus providing useful guidelines for designing filters with suitable responses. As a consequence of this simplified topology, any designed filter can be easily manufactured by cutting along its E-field symmetry plane. This strategy greatly improves the filter’s insertion loss regarding classical implementations based on more complicated arrangements with piled thin metallic sheets. Two exemplary filters have been designed and tested to be used in a high-performance X-band SATCOM terminal with an 80% size reduction with respect to the existing systems. Both filters covering the Rx (7.25–75 GHz) and Tx (7.9–8.4 GHz) sub-bands show a reflection of −25 dB with insertion losses below 1 dB in the pass-band, whereas they present a very sharp out-of-band rejection of at least 90 dB, that is, a 600 dB/GHz slope at X band.

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