612-14-6Relevant articles and documents
Crossover point between dialkoxy disulfides (ROSSOR) and thionosulfites ((RO)2S=S): Prediction, synthesis, and structure
Zysman-Colman, Eli,Nevins, Neysa,Eghball, Nicolas,Snyder, James P.,Harpp, David N.
, p. 291 - 304 (2006)
Isomeric preference between cyclic dialkoxy disulfides and thionosulfites is governed by the ring size of the heterocycle, Rings smaller than seven atoms prefer the thionosulfite connectivity, whereas larger rings or acyclic analogues favor the unbranched dialkoxy disulfide structure, Density functional calculations were employed to predict the crossover point at which both constitutional isomers are of comparable stability. Follow-up synthesis provides the previously unknown eight-membered ring dialkoxy disulfide 14 and seven-membered ring thionosulfite 15 from the same reaction. X-ray crystallography for all but one of the reaction products and complementary NMR analysis furnishes insights into both solid-state and solution conformations, A long-standing issue regarding the concerted vs catalyzed Isomerization pathway between XSSX and X2S=S has been addressed for X = RO and shown to be acid dependent.
RAFT/MADIX copolymerization of vinyl acetate and 5,6-benzo-2-methylene-1,3- dioxepane
D'Ayala, Giovanna Gomez,Malinconico, Mario,Laurienzo, Paola,Tardy, Antoine,Guillaneuf, Yohann,Lansalot, Muriel,D'Agosto, Franck,Charleux, Bernadette
, p. 104 - 111 (2014)
The synthesis of well-defined degradable poly(vinyl acetate) analogues is achieved by RAFT copolymerization of 5,6-benzo-2-methylene-1,3-dioxepane (BMDO) and vinyl acetate (VAc) using methyl (ethoxycarbonothioyl)sulfanyl acetate (MEA) as controlling agent. Several monomer mixtures with low BMDO contents (30 mol %) are employed to prepare different copolymers. In all the cases, the evolution of molar masses and the dispersity values (1.26) confirm the controlled feature of the polymerization. The livingness of the obtained chains is demonstrated by successful chain extension experiments with VAc, although the presence of dead chains is also shown. The introduction of ester groups into the main chain of these P(VAc-co-BMDO) copolymers allows their degradation when treated with a mixture of KOH/MeOH in reflux during 2.5 h.
High Efficiency Catalytic Transfer Hydrogenation of Furfural to Furfuryl Alcohol Over Metallic Oxide Catalyst
Liu, Zonghui,Wen, Zhe,Xue, Bing,Zhang, Zhongze
, (2022/02/07)
Development of simple and high performance solid catalysts for the utilization of biomass has become an important research topic in heterogeneous catalysis and sustainable chemistry. Herein, a highly efficient catalytic system was studied for the catalytic transfer hydrogenation of furfural to high value furfuryl alcohol over a series of acidic or basic oxides catalysts. Among those oxides, acidic Al2O3 is identified as the most effective for FAL production, giving a FUR conversion as high as 40% (FUR consumption rate was 186?mmol gcat?1 h?1) and FAL selectivity of 99% after only 5?min at 150?°C using 2-propanol as the H-donor and solvent. Furthermore, the as prepared Al2O3 give an Ea value of 15.2?kJ/mol, which is much lower than other complex catalysts in the literatures. Correlating the catalyst performance with its physical and chemical properties uncovers that the large specific surface area and high acidity of Al2O3 would be the key to the catalyst performance. Graphical Abstract: [Figure not available: see fulltext.]
Novel substituted N-benzyl(oxotriazinoindole) inhibitors of aldose reductase exploiting ALR2 unoccupied interactive pocket
Hlavá?, Matú?,Ková?iková, Lucia,?oltésová Prnová, Marta,Addová, Gabriela,Hanquet, Gilles,?tefek, Milan,Bohá?, Andrej
supporting information, (2020/12/09)
Recently we have developed novel oxotriazinoindole inhibitors (OTIs) of aldose reductase (ALR2), characterized by high efficacy and selectivity. Herein we describe novel OTI derivatives design of which is based on implementation of additional intermolecular interactions within an unoccupied pocket of the ALR2 enzyme. Four novel derivatives, OTI-(7–10), of the previously developed N-benzyl(oxotriazinoindole) inhibitor OTI-6 were synthetized and screened. All of them revealed 2 to 6 times higher ALR2 inhibitory efficacy when compared to their non-substituted lead compound OTI-6. Moreover, the most efficient ALR2 inhibitor OTI-7 (IC50 = 76 nM) possesses remarkably high inhibition selectivity (SF ≥ 1300) in relation to structurally related aldehyde reductase (ALR1). Derivatives OTI-(8–10) bearing the substituents –CONH2, –COOH and –CH2OH, possess 2–3 times lower inhibitory efficacy compared to OTI-7, but better than the reference inhibitor OTI-6. Desolvation penalty is suggested as a possible factor responsible for the drop in ALR2 inhibitory efficacy observed for derivatives OTI-(8–10) in comparison to OTI-7.
A Unified Catalytic Asymmetric (4+1) and (5+1) Annulation Strategy to Access Chiral Spirooxindole-Fused Oxacycles
Gao, Min,Gong, Xiangnan,Hu, Lin,Luo, Yanshu,Xia, Yuanzhi,Xu, Qianlan,Zhao, Yukun
supporting information, p. 19813 - 19820 (2021/08/03)
A unified catalytic asymmetric (N+1) (N=4, 5) annulation reaction of oxindoles with bifunctional peroxides has been achieved in the presence of a chiral phase-transfer catalyst (PTC). This general strategy utilizes peroxides as unique bielectrophilic four- or five-atom synthons to participate in the C?C and the subsequent umpolung C?O bond-forming reactions with one-carbon unit nucleophiles, thus providing a distinct method to access the valuable chiral spirooxindole-tetrahydrofurans and -tetrahydropyrans with good yields and high enantioselectivities under mild conditions. DFT calculations were performed to rationalize the origin of high enantioselectivity. The gram-scale syntheses and synthetic utility of the resultant products were also demonstrated.
