219945-37-6Relevant academic research and scientific papers
Crystalline Isotactic Polar Polypropylene from the Palladium-Catalyzed Copolymerization of Propylene and Polar Monomers
Ota, Yusuke,Ito, Shingo,Kobayashi, Minoru,Kitade, Shinichi,Sakata, Kazuya,Tayano, Takao,Nozaki, Kyoko
, p. 7505 - 7509 (2016)
Moderately isospecific homopolymerization of propylene and the copolymerization of propylene and polar monomers have been achieved with palladium complexes bearing a phosphine-sulfonate ligand. Optimization of substituents on the phosphorus atom of the ligand revealed that the presence of bulky alkyl groups (e.g. menthyl) is crucial for the generation of high-molecular-weight polypropylenes (Mw≈104), and the substituent at the ortho-position relative to the sulfonate group influences the molecular weight and isotactic regularity of the obtained polypropylenes. Statistical analysis suggested that the introduction of substituents at the ortho-position relative to the sulfonate group favors enantiomorphic site control over chain end control in the chain propagation step. The triad isotacticity could be increased to mm=0.55–0.59, with formation of crystalline polar polypropylenes, as supported by the presence of melting points and sharp peaks in the corresponding X-ray diffraction patterns.
Methods for the preparation of biphenyl isoxazole sulfonamides
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, (2008/06/13)
Methods for the preparation of biphenyl isoxazole sulfonamides and intermediates therof. The present invention also relates to the novel intermediates prepared by these methods. The biphenyl isoxazole sulfonamides prepared by the present methods are endot
Biphenylsulfonamide endothelin antagonists: Structure-activity relationships of a series of mono- and disubstituted analogues and pharmacology of the orally active endothelin antagonist 2'-amino-N-(3,4- dimethyl-5-isoxazolyl)-4'-(2-methylpropyl)[1,1'-biphenyl]-2-sulfonamide (BMS- 187308)
Murugesan, Natesan,Gu, Zhengxiang,Stein, Philip D.,Bisaha, Sharon,Spergel, Steve,Girotra, Ravi,Lee, Ving G.,Lloyd, John,Misra, Raj N.,Schmidt, Joan,Mathur, Arvind,Stratton, Leslie,Kelly, Yolanda F.,Bird, Eileen,Waldron, Tom,Liu, Eddie C.-K.,Zhang, Rongan,Lee, Helen,Serafino, Randy,Abboa-Offei, Benoni,Mathers, Parker,Giancarli, Mary,Seymour, Andrea Ann,Webb, Maria L.,Moreland, Suzanne,Barrish, Joel C.,Hunt, John T.
, p. 5198 - 5218 (2007/10/03)
Substitution at the ortho position of N-(3,4-dimethyl-5-isoxazolyl) benzenesulfonamide led to the identification of the biphenylsulfonamides as a novel series of endothelin-A (ETA) selective antagonists. Appropriate substitutions on the pendant phenyl ring led to improved binding as well as functional activity. A hydrophobic group such as isobutyl or isopropoxyl was found to be optimal at the 4'-position. Introduction of an amino group at the 2'-position also led to improved analogues. Combination of the optimal 4'- isobutyl substituent with the 2'-amino function afforded an analogue (20, BMS-187308) with improved ET(A) binding affinity and functional activity. Compound 20 also has good oral activity in inhibiting the pressor effect caused by an ET-1 infusion in rats. Doses of 10 and 30 μmol/kg iv 20 attenuated the pressor responses due to the administration of exogenous ET-1 to conscious monkeys, indicating that the compound inhibits the in vivo activity of endothelin-1 in nonhuman primates.
