536-57-2Relevant articles and documents
Effect of partial hydrogenation on the phase behavior of poly(isoprene-b-styrene-b-methyl methacrylate) triblock copolymers
Tureau, Maeva S.,Epps, Thomas H.
, p. 8347 - 8355 (2012)
We studied the effect of selective hydrogenation of the polyisoprene block in poly(isoprene-b-styrene-b-methyl methacrylate) (ISM) triblock copolymers on nanoscale network phase formation. The morphologies of the resulting poly((ethylene-alt-propylene)-b-styrene-b-methyl methacrylate) (EPSM) triblock copolymers and several EPSM copolymer/homopolymer blends were investigated using a combination of small-angle X-ray scattering and transmission electron microscopy, where well-ordered HEX, SA, and Q230 (network) nanostructures were identified. Variations in the nanoscale morphologies and phase boundaries between EPSM copolymers and their corresponding ISM precursors can be attributed to the differences in conformational asymmetry and block interactions. Of particular interest, the growth in the gyroid network region in the EPSM relative to the ISM is highlighted as the expansion of this region could further enable the creation of network-forming nanoporous membranes made from materials that are expected to demonstrate improved resistance against thermal and oxidative degradation.
Anthracene Heme Cyclophanes. Steric Effects in CO, O2, and RNC Binding
Traylor, T. G.,Tsuchiya, Shinji,Campbell, Dwane,Mitchell, Michael,Stynes, Dennis,Koga, Noboru
, p. 604 - 614 (1985)
Equilibrium constants in benzene solution are reported for binding of imidazoles, CO, O2, and isocyanide to two anthracene heme cyclophanes, Fe(6,6-cyclophane) and Fe(7,7-cyclophane), containing a conformationally mobile anthracene ring strapped symmetrically over the heme.The Fe(6,6-cyclophane) shows an approximately 300-fold reduction in affinity for the diatomic molecules, CO, and O2 compared to unhindered hemes.The Fe(7,7-cyclophane) shows only slight steric effects toward CO and O2 but larger effects with bulky isocyanides.The sizes of the cyclophane cavities are qualitatively probed with isocyanides of varying size.Kinetic data for binding of CO, O2, and tosylmethyl isocyanide to heme cyclophanes when compared to similar data for flat analogues demonstrate that steric effects are manifested primarily in the ligand association rates.This feature of the cyclophane is very similar to observed steric effects in hemoproteins, suggesting that large conformational changes (tilting of the cyclophane cap in the models and movement of distal protein residues in hemoproteins) occur in both prior to the transition state for ligation.Magnitudes of steric effects in hemoproteins and cyclophanes are calculated on the basis of comparison with the unhindered chelated heme model compounds.The nature of the distal steric effect in the Fe(6,6-cyclophane) model compound suggests that the reported bending or tilting of CO in hemoglobins and myoglobin may be of minor chemical significance.
Photoredox Catalyzed Sulfonylation of Multisubstituted Allenes with Ru(bpy)3Cl2 or Rhodamine B
Chen, Jingyun,Chen, Shufang,Jiang, Jun,Lu, Qianqian,Shi, Liyang,Xu, Zekun,Yimei, Zhao
supporting information, (2021/11/09)
A highly regio- and stereoselective sulfonylation of allenes was developed that provided direct access to α, β-substituted unsaturated sulfone. By means of visible-light photoredox catalysis, the free radicals produced by p-toluenesulfonic acid reacted with multisubstituted allenes to obtain Markovnikov-type vinyl sulfones with Ru(bpy)3Cl2 or Rhodamine B as photocatalyst. The yield of this reaction could reach up to 91%. A series of unsaturated sulfones would be used for further transformation to some valuable compounds.
Styrene sulfone NLRP3 inflammasome inhibitor, preparation method and application thereof
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Paragraph 0053; 0064-0065, (2020/10/30)
The invention relates to the field of styrene sulfone compounds and NLRP3 inhibitors, and particularly provides a styrene sulfone NLRP3 inflammasome inhibitor, a preparation method and application thereof, wherein the inhibitor is represented by a formula (1), n is selected from 0 and 1, X is selected from N and O, R1 is selected from different electron withdrawing or electron donating substituents, and R2 is selected from different fat or aromatic substituents. According to the invention, it is verified that the compounds represented by the general formula have NLRP3 inhibitory activity.
Visible-Light-Induced Radical Cascade Cyclizations of 1,7-Enynes with Sulfinic Acids: Direct Access to Sulfonated Chromanes and Sulfonated Tetrahydroquinolines under Metal-Free Conditions
Liu, Qi,Mei, Yousheng,Wang, Lei,Ma, Yongmin,Li, Pinhua
supporting information, p. 5669 - 5680 (2020/10/28)
Visible-light-induced strategy to access sulfonated chromanes and sulfonated 1,2,3,4-tetrahydroquinolines via a radical cascade cyclization of 1-(arylethynyl)-2-(vinyloxy)benzenes and N-allyl-2-(arylethynyl)anilines with aromatic and aliphatic sulfinic acids has been developed. In the presence of TBHP (7.5 mol%) as an oxidant and Eosin Y (3.0 mol%) as a photocatalyst, the reactions undergo smoothly to afford the corresponding products in good yields at room temperature under metal-free conditions. This transformation features low loading of TBHP, mild reaction conditions, simple operation, broad functional-group tolerance, and good yields of products. (Figure presented.).
Water-Promoted Dehydrative Tsuji–Trost Reaction of Non-Derivatized Allylic Alcohols with Sulfinic Acids
Yu, Jing,Chang, Xueping,Ma, Ruitian,Zhou, Qiuju,Wei, Mengmeng,Cao, Xinhua,Ma, Xiantao
supporting information, p. 7238 - 7242 (2020/10/30)
A mild, green and extra activator-free synthesis of allylic sulfones from non-derivatized allylic alcohols and sulfinic acids was developed and only the easily-available Pd(PPh3)4 was used as the catalyst. This new method could be easily scaled up to gram scale, affording the target allylic sulfones in a nearly quantitative yield with water as the sole by-product. Mechanism studies both by various NMR techniques and by theoretical calculations suggested two reaction pathways may be involved in the reaction, which are dependent on the reaction media, that is, an eight-membered ring binding species may be formed in aqueous media between allylic alcohol, sulfinic acid and water, while a six-membered ring binding species may be formed in common aprotic organic solvent between allylic alcohol and sulfinic acid. Both binding species may be accounted for the efficient activation of allylic alcohols via hydrogen bonding.
Sustainable access to sulfonic acids from halides and thiourea dioxide with air
Zhang, Hui,Wang, Ming,Jiang, Xuefeng
supporting information, p. 8238 - 8242 (2020/12/29)
A sustainable and mild one-step strategy is explored for the synthesis of aryl and alkyl sulfonic acids using a facile combination of halides and sulfur dioxide surrogates under air. The cheap industrial material thiourea dioxide was employed as an eco-friendly and easy-handling sulfur dioxide surrogate, while air was used as a green oxidant. Both aryl and alkyl sulfonic acids were obtained under transition metal-catalyzed or transition metal-free conditions. Mechanistic studies demonstrated that sulfinate was involved as an intermediate in this transformation. Notably, this protocol has been applied to the late-stage sulfonation of the drugs naproxen, isoxepac and ibuprofen.
Efforts towards an On-Target Version of the Groebke–Blackburn–Bienaymé (GBB) Reaction for Discovery of Druglike Urokinase (uPA) Inhibitors
Gladysz, Rafaela,Vrijdag, Johannes,Van Rompaey, Dries,Lambeir, Anne-Marie,Augustyns, Koen,De Winter, Hans,Van der Veken, Pieter
supporting information, p. 12380 - 12393 (2019/09/06)
Target-guided synthesis (TGS) has emerged as a promising strategy in drug discovery. Although reported examples of TGS generally involve two-component reactions, there is a strong case for developing target-guided versions of three-component reactions (3CRs) because of their potential to deliver highly diversified druglike molecules. To this end, the Groebke–Blackburn–Bienaymé reaction was selected as a model 3CR. We recently reported a series of druglike urokinase inhibitors, and these serve as reference compounds in the present study. Due to the limited number of literature reports on target-guided 3CRs, multiple experimental parameters were optimized here. Most challenging was the formation of imine intermediates under near-physiological conditions. This aspect was addressed by exploring chemical imine stabilization strategies. Notably, imines are also crucial intermediates of other 3CRs. Such systematic studies are strongly required for further development of the TGS domain but are largely absent in the literature. Hence, this work is intended as a reference for future multicomponent-based TGS studies.
Novel Compounds Targeting the RNA-Binding Protein HuR. Structure-Based Design, Synthesis, and Interaction Studies
Della Volpe, Serena,Nasti, Rita,Queirolo, Michele,Unver, M. Yagiz,Jumde, Varsha K.,D?mling, Alexander,Vasile, Francesca,Potenza, Donatella,Ambrosio, Francesca Alessandra,Costa, Giosué,Alcaro, Stefano,Zucal, Chiara,Provenzani, Alessandro,Di Giacomo, Marcello,Rossi, Daniela,Hirsch, Anna K. H.,Collina, Simona
supporting information, p. 615 - 620 (2019/04/25)
The key role of RNA-binding proteins (RBPs) in regulating post-transcriptional processes and their involvement in several pathologies (i.e., cancer and neurodegeneration) have highlighted their potential as therapeutic targets. In this scenario, Embryonic Lethal Abnormal Vision (ELAV) or Hu proteins and their complexes with target mRNAs have been gaining growing attention. Compounds able to modulate the complex stability could constitute an innovative pharmacological strategy for the treatment of numerous diseases. Nevertheless, medicinal-chemistry efforts aimed at developing such compounds are still at an early stage. As part of our ongoing research in this field, we hereby present the rational design and synthesis of structurally novel HuR ligands, potentially acting as HuR-RNA interferers. The following assessment of the structural features of their interaction with HuR, combining saturation-transfer difference NMR and in silico studies, provides a guide for further research on the development of new effective interfering compounds of the HuR-RNA complex.
The base-free van Leusen reaction of cyclic imines on water: Synthesis of N-fused imidazo 6,11-dihydro β-carboline derivatives
Satyam, Killari,Murugesh,Suresh, Surisetti
supporting information, p. 5234 - 5238 (2019/06/07)
Construction of imidazoles has been demonstrated on water under base-free conditions. The reaction of dihydro β-carboline imines and p-toluenesulfonylmethyl isocyanides furnished the corresponding substituted N-fused imidazo 6,11-dihydro β-carboline derivatives in very good yields under ambient conditions. The use of deuterium oxide (D2O) as a solvent enabled the incorporation of deuterium isotopes in the imidazole ring.
