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... The role of poly(ε-caprolactone) (PCL) and its 3D scaffolds in tissue engineering has already been established due to its ease of processing into long-term degradable implants and approval from the FDA. This review presents the role of high internal phase emulsion (HIPE) templating in the fabrication of PCL scaffolds, and the versatility of the technique along with challenges associated with it. C ...
... The catalyst-free addition of N,N-difluorobenzenesulfonamides (DFBSA) with α-methylstyrenes and the in-situ-N–F bond hydrolysis of the adducts were accomplished. N-fluoro-N-hydroxy-β-amine ethyl sulfonyl derivatives were obtained in moderate yields, particularly, the water needed for hydrolysis originated from the reaction system without additional supply. The results of several control experiment ...
freeradicals, etc ; acrylamides; alkenes; organic chemistry; Show all 4 Subjects
Abstract:
... Free radical carbochloromethylations of ortho-cyanoarylacrylamides and N-(arylsulfonyl)acrylamides have been developed by employing simple alkyl chlorides as the chloromethyl source. The transformations are characterized by wide functional group compatibility and utilizing readily available reagents, thus providing efficient methods for constructing polychloromethyl-substituted quinoline-2,4-dione ...
freeradicals, etc ; benzene; carboxylation; catalysts; nickel; Show all 5 Subjects
Abstract:
... It has always been a challenge in free radical chemistry to control site selectivity during the reaction of free radicals with aromatic rings. Herein, we report the site-selective carboxylation of anisoles through the direct reaction of the bromoform radical with a benzene ring at the para position under the assistance of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline with nickel(II) as the catalys ...
freeradicals, etc ; chemical reactions; genes; topology; transfection; Show all 5 Subjects
Abstract:
... Topological structure plays a critical role in gene delivery of cationic polymers. Cyclic poly(β-amino ester)s (CPAEs) are successfully synthesized via sequential Michael addition and free radical initiating ring-closure reaction. The CPAEs exhibit superior gene transfection efficiency and safety profile compared to their linear counterparts. ...
freeradicals, etc ; cysteine; glutathione; organic chemistry; thiols; Show all 5 Subjects
Abstract:
... The addition of thiol compounds to o-quinones, as exemplified by the biologically relevant conjugation of cysteine to dopaquinone, displays an anomalous 1,6-type regiochemistry compared to the usual 1,4-nucleophilic addition, for example, by amines, which has so far eluded intensive investigations. By means of an integrated experimental and computational approach, herein, we provide evidence that ...
freeradicals, etc ; molecular imprinting; polymerization; polymers; sorption; Show all 5 Subjects
Abstract:
... Molecularly imprinted polymers (MIP) have shown their potential as artificial and selective receptors for environmental monitoring. These materials can be tailor-made to achieve a specific binding event with a template through a chosen mechanism. They are capable of emulating the recognition capacity of biological receptors with superior stability and versatility of integration in sensing platform ...
freeradicals, etc ; ligands; schiff bases; stoichiometry; thermogravimetry; vanillin; Show all 6 Subjects
Abstract:
... In this current work we have prepared a Schiff base ligand, (HL) derived from 5- nitropyridine-2-amine with 4-hydroxy-3-methoxybenzaldehyde and its Cu(II), and Zn(II) in 2:1 stoichiometric ratio (2HL:M). The formation of the ligand and the metal complexes were evaluated by means of MS, FT-IR, UV-Visible, ¹H-NMR, ¹³C-NMR and thermogravimetric methods. The free radical scavenging activity of compoun ...
freeradicals, etc ; Lewis bases; complement; regioselectivity; transition elements; Show all 5 Subjects
Abstract:
... Oxetanes are valuable building blocks due to their well-explored propensity to undergo ring-opening reactions with nucleophiles. However, their application as precursors of radical species is still elusive. Herein, we present a bioinspired cobalt-catalysis-based strategy to access unprecedented modes of radical reactivity via oxetane ring-opening. This powerful approach gives access to nucleophili ...
freeradicals, etc ; X-ray diffraction; alkynes; organic chemistry; Show all 4 Subjects
Abstract:
... Persulfate-promoted radical cascade trifluoromethylthiolation of aryl acetylenes with AgSCF₃ provides a simple reaction system for the synthesis of SCF₃-substituted dibenzazepines or dioxodibenzothiazepines with good Z/E selectivity. The single-crystal X-ray diffraction data confirms the structures of the final products. A series of scaled-up experiments, further transformations, and radical inhib ...
freeradicals, etc ; chemical communication; gases; ions; ligands; solvents; Show all 6 Subjects
Abstract:
... Cu complexes with p-dimethylaminophenolate ligands were synthesized by the reaction of Cuᴵᴵ ions with the ligands under inert gas atmosphere and characterized. The complexes showed a valence state change from Cuᴵᴵ–phenolate to Cuᴵ–phenoxyl radical on loss of the coordinated solvent. The Cuᴵ–phenoxyl radical species showed the characteristic properties and reactivities. ...
freeradicals, etc ; cyclization reactions; fluorescence; heterocyclic compounds; photocatalysts; Show all 5 Subjects
Abstract:
... A simple and mild approach to access polycyclic 8H-indolo[3,2,1-de]phenanthridin-8-ones through a visible-light induced free radical cyclization of (2-bromophenyl)(9H-carbazol-9-yl)methanones using benzothiadiazole-containing photocatalyst is reported. This transition metal free method can be utilized for the synthesis of 7H-thieno[2′,3′:4,5]pyrido[3,2,1-jk]carbazol-7-one, 14H-isoquinolino[4,3,2-k ...
freeradicals, etc ; application methods; bioactive compounds; drugs; exhibitions; methodology; Show all 6 Subjects
Abstract:
... Trifluoroethyl (CH₂CF₃) is an important functional group in many pharmaceutical and agrochemical compounds. Herein, we report an efficient method for the copper-catalyzed direct trifluoroethylation of heteroarenes. The reaction exhibited good compatibility to various substrates, and the desired products were obtained in good yields. Preliminary mechanistic investigations indicate the trifluoroethy ...
freeradicals, etc ; catalytic activity; oxidation; p-nitrophenol; silver; wastewater; Show all 6 Subjects
Abstract:
... Silver-based materials have emerged as excellent catalysts for peroxymonosulfate (PMS) activation in wastewater pollutants degradation. However, the mechanism of pure silver oxides towards PMS activation remains insufficient. In this work, Ag₂O and AgO were selected as typical silver oxides to detect the catalytic performance. AgO/PMS possessed higher activity for p-nitrophenol and other pollutant ...
freeradicals, etc ; hydrogels; hydrolysis; microgels; polymerization; sodium dodecyl sulfate; Show all 6 Subjects
Abstract:
... Microgels are soft, adaptive materials exhibiting various properties not only like hydrogels and microparticles but also like macromolecules, colloids, and surfactants. To widen the range of their biomedical and environmental applications, the exploration of an alternative for poly(N-alkylacrylamide)s without potential safety risks is of great importance. In this article, thermoresponsive poly(N-v ...
freeradicals, etc ; azo compounds; esters; hydrazides; journals; organic chemistry; Show all 6 Subjects
Abstract:
... A new chemistry of azo compounds, that is, addition of free radicals generated in situ to access various acyl hydrazides, has been developed. The protocol provides a novel strategy for the synthesis of valuable acyl hydrazides. The transformation features mild reaction conditions, good tolerance of functional groups, and a broad substrate scope. In view of the importance of acyl hydrazides in func ...
freeradicals, etc ; antineoplastic activity; biological assessment; chitosan; esterification; selenium; Show all 6 Subjects
Abstract:
... Though great efforts have been made to develop selenium polysaccharides with unique properties using HNO₃-Na₂SeO₃ methods, the Se content is still low due to the poor esterification efficiency of H₂SeO₃. Herein, selenodiacetic acid (SA) was introduced into chitosan (CS) to synthesize O-selenodiacetyl chitosan (OSAC) and chitosan-ammonium selenodiacetate (CASA) by covalent and non-covalent interact ...
freeradicals, etc ; antioxidant activity; energy; food chemistry; oxidative stress; peptides; Show all 6 Subjects
Abstract:
... The protective effects of the peptides Asp-Asp-Asp-Tyr (DDDY) and Asp-Tyr-Asp-Asp (DYDD) against AAPH-induced HepG2 cells are unclear. Our objective was to investigate the active sites of these peptides and their cellular antioxidant mechanism. DDDY and DYDD show a direct free radical scavenging effect in reducing ROS levels and maintained cellular antioxidant enzymes at normal levels. The quantum ...
freeradicals, etc ; Dehalococcoides; biofilm; chlorine; dechlorination; mineralization; oxidation; remediation; sulfates; Show all 9 Subjects
Abstract:
... Polychlorinated biphenyls (PCBs) as typical halogenated persistent organic pollutants are widely distributed in natural environments, and can be enriched and magnified in organisms via food webs. It is consequently urgent and necessary to develop techniques to completely remove these persistent organohalides. In this study, we developed a process (Bio-RD-PAOP) by integrating microbial reductive de ...
freeradicals, etc ; catalytic activity; combustion; droplets; energy; evaporation; hydrogen; kerosene; temperature; Show all 9 Subjects
Abstract:
... Turbine-based combined cycle (TBCC) engines, which consist of turbine and scramjet engines, are a key power system for the acceleration, powered horizontal landing, and reuse of hypersonic vehicles. Low Mach number ignition of kerosene-based scramjet fuel is expected to enable the practical application of TBCC engines. However, ignition under these conditions is extremely difficult to achieve. In ...