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.
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.
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.
