An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
alcohols, etc ; aerogels; carbon; carbon fibers; delamination; epoxides; polyvinyl alcohol; skeleton; toxicity; Show all 9 Subjects
Abstract:
... Interlaminar delamination is the most prevalent failure mode for carbon fiber reinforced epoxy (CF/EP) composites, which limits its applications. In this work, the interlaminar fracture toughness of CF/EP composites has been enhanced by the self-interlocked network arisen from Ti₃C₂Tₓ/polyvinyl alcohol (PVA) aerogel (TPA). The failure mode and toughening mechanism of interlocked TPA/CF/EP laminate ...
alcohols, etc ; adsorption; arsenic; environment; filtration; hydrogels; models; nanoparticles; pH; polymers; protonation; sorption isotherms; Show all 12 Subjects
Abstract:
... A modified chitosan-polyvinyl alcohol (PVA) hydrogel was developed by incorporating Fe₃O₄ nanoparticles. Four chitosan-Fe₃O₄ (ChFe) hydrogel types were developed based on chitosan:Fe₃O₄ ratio as 1:0, 1:1, 1:0.5 and 1:0.25. Batch sorption experiments were conducted with different pH, dosage, kinetics, and isotherms. The exhausted ChFe hydrogels were evaluated for their regeneration and reuse capabi ...
alcohols, etc ; absorption; cluster analysis; data collection; discriminant analysis; fluorescence; food safety; fructose; glucose; pH; principal component analysis; titratable acidity; wines; Show all 13 Subjects
Abstract:
... Authentication of wine can be considered at different scales, with classification according to country, province/state, or appellation/wine producing region. An absorbance-transmission and excitation-emission matrix (A-TEEM) technique was applied for the first time to examine intraregional differences, using Shiraz wines (n = 186) produced during three vintages from five subregions of Barossa Vall ...
alcohols, etc ; anticonvulsants; anxiety; benzodiazepines; bile; blood; central nervous system; epilepsy; forensic sciences; illicit drugs; markets; medical treatment; metabolites; sedatives; sleep disorders; toxicity testing; urine; Show all 17 Subjects
Abstract:
... Benzodiazepines exhibit central nervous system depressive activity as well as sedative, hypnotic, and anticonvulsant properties, which enable to use them as medical treatment in anxiety, epilepsy, insomnia and alcohol withdrawal syndrome. However, from 2000s illegal benzodiazepine derivatives have started to emerge on illicit drug market as new psychoactive substances (NPSs) monitored in many coun ...
... Due to the public health concern of arsenic, environmental management measures in mining areas had been implemented. To assess the effect of environmental management measures in the mining area comprehensively, arsenic accumulation in the urine, hair, nails, and urinary metabolites of residents in a realgar mining area in Hunan province, China were investigated in 2019, and the changes in arsenic ...
alcohols, etc ; Ayurvedic medicine; Lagenaria siceraria; albino; animals; atorvastatin; bioinformatics; computer simulation; ferulic acid; food plants; hesperidin; high fat diet; hyperlipidemia; hypertension; insulin; lipids; mechanism of action; metabolites; obesity; p-coumaric acid; pharmacology; Show all 21 Subjects
Abstract:
... Lagenaria siceraria Stand. (Family: Cucurbitaceae), popularly known as bottle gourd, is traditionally used in Ayurvedic medicine as a food plant, especially in hypertension and obesity. Investigations were undertaken to assign novel lead combinations from this common food plant to multi-molecular modes of actions in the complex disease networks of obesity and hypertension. LC–MS/MS based metabolit ...
... An efficient synthesis of 2-aryl-4-chloro-tetrahydropyrans has been accomplished from benzyl chlorides and homoallylic alcohols using FeCl₃ as a promoter through a sequential oxidation/Prins cyclization in high yields. This is the first report on the use of benzyl chlorides as surrogates for aldehydes in the Prins cyclization. ...
... Pt particles anchored onto Mn₃O₄ cubes were found to have high anti-CO poisoning abilities for C1- and C2-alcohol fuel oxidations in acid electrolyte, due to an electronic effect that enriched the surfaces of the Pt particles with electrons and due to the oxophilicity of Mn₃O₄ in the system. ...
... Two acid-catalyzed tandem reactions between 4-hydroxy-1-methylquinolin-2(1H)-one and propargylic alcohols are described. Depending mainly on the propargylic alcohol used, these tandem reactions proceed via either a Friedel–Crafts-type allenylation followed by 6-endo-dig cyclization sequence to form pyrano[3,2-c]quinolones or a Friedel–Crafts-type alkylation and 5-exo-dig ring closure sequence to a ...
... A stereoselective synthetic entry point to the 5–8–5 carbocyclic core of the ophiobolins was developed. This strategy exploits the chiral tertiary alcohol of ophiobolin A to guide assmebly of the 5–8–5 scaffold in a single step via a photoinitiated cycloisomerization. Mechanistic insights into the origin of stereocontrol in this reaction are described, as are efforts to elaborate the resultant fus ...
... The reduction of benzylic, tertiary, and allylic alcohols with hydrosilane was efficiently catalyzed by the rhenium complex, such as ReBr(CO)₅, to give the corresponding deoxygenarated products, alkanes, in moderate to good yields. In the case of aliphatic secondary alcohol, the alkane was formed along with the formation of dehydrated products. On the other hand, in the case of primary and cyclic ...
... Development of the convenient method for the synthesis of (hydroxyphenyl)perfluoro-alkylmethanols was achieved by the Meerwein-Ponndorf-Verley (MPV) type reduction of the in situ-generated perfluoroalkylated ketones as the key step. The benzylic OH group of the resultant alcohols was successfully converted to H or Rf(CH₂)ₙO by way of the corresponding chlorides, this transformation being not easy ...
... A two-step synthesis of geminal divinyl compounds from ketones was developed. An allyl titanium reagent prepared from 1-phenylthio-4-trimethylsilyl-2-butene was reacted with a ketone, and the resulting tertiary alcohol was subjected to a Brønsted acid-mediated rearrangement reaction to generate a geminal divinyl compound. Introduction of another alkene moiety followed by ring closing metathesis re ...
... The gem-difluoroalkene moiety is an ideal carbonyl bioisostere in medicinal chemistry, but efficient synthesis of β-gem-difluoroalkene esters remains challenging so far. Herein, we disclose a photoredox-catalyzed allylic defluorinative alkoxycarbonylation of trifluoromethyl alkenes enabled by intermolecular alkoxycarbonyl radical addition. A wide variety of alcohol oxalate derivatives were amenabl ...
... Among the famous Daphniphyllum alkaloids family, the calyciphylline A-type subfamily has triggered particular interest from the organic synthesis community in recent years. Here, we report divergent total syntheses of three calyciphylline A-type alkaloids, namely, (−)-10-deoxydaphnipaxianine A, (+)-daphlongamine E, and (+)-calyciphylline R. Our work highlights an efficient, divergent strategy via ...
alcohols, etc ; acylation; enantioselectivity; methodology; Show all 4 Subjects
Abstract:
... A novel highly enantioselective method for the kinetic resolution of racemic tertiary alcohols has been achieved through chiral organotin-catalyzed intermolecular acylation of the hydroxyl group. This process has demonstrated a broad substrate scope (both alkyl- and aryl-substituted tertiary alcohols) with high enantioselectivity under mild reaction conditions, affording the corresponding products ...
... This review paper provides an overview of the main strategies for the oxidative esterification of thiols with alcohols. The review is divided into two major parts according to final products. The first includes the methods for the synthesis of sulfinic esters, while the second contains the procedures for the fabrication of sulfonic ester derivatives. ...
... A strategy for the synthesis of substituted and strained p-phenylene units is reported. An oxidative allylic alcohol rearrangement, followed by organometallic addition to the resulting α-ketol and subsequent dehydrative aromatization, affords p-terphenyl-containing macrocycles in which the central p-phenylene has been selectively substituted. Ten 18-membered macrocycles have been synthesized, eigh ...
... A series of β-mono- and β,γ-di-substituted α-methylene-γ-lactams was synthesized. This method involves the 1,4-addition of nitroalkanes to arylidenemalonates to obtain nitro derivatives using a conventional method and microwave irradiation. Subsequent nitro reduction provided α-carbomethoxy-γ-lactam, a versatile molecule that was used to obtain the alcohol. After alcohol, the mesylate was obtained ...
alcohols, etc ; couplings; indoles; libraries; methodology; Show all 5 Subjects
Abstract:
... Indole-based diversification is highly desired in the DNA-encoded chemical library construction. Herein, we present a general strategy for on-DNA synthesis of diverse C3-functionalized indole derivatives via indole π-activated alcohol formation followed by direct dehydrative coupling. Highly efficient bond linkages of C–C, C–N, and C–S were achieved to fuse building blocks that are widely commerci ...