18760-47-9Relevant articles and documents
Alkyl substituted [6,6]-thienyl-C61-butyric acid methyl esters: Easily accessible acceptor materials for bulk-heterojunction polymer solar cells
Zhao, Huiyu,Guo, Xiaoyang,Tian, Hongkun,Li, Changyin,Xie, Zhiyuan,Geng, Yanhou,Wang, Fosong
, p. 3092 - 3097 (2011/07/30)
[6,6]-Thienyl-C61-butyric acid ester derivatives with methyl, hexyl and 2-ethylhexyl at the 5-position of thiophene ring (TCBM-Cn, n represents the number of carbon atom in the alkyl chain) were synthesized. Unlike [6,6]-phenyl-C61-b
Michael addition of stannyl ketone enolate to α,β-unsaturated esters catalyzed by tetrabutylammonium bromide and an ab initio theoretical study of the reaction course
Yasuda, Makoto,Chiba, Kouji,Ohigashi, Noriyuki,Katoh, Yasuhiro,Baba, Akio
, p. 7291 - 7300 (2007/10/03)
Michael addition of stannyl ketone enolates to α,β-unsaturated esters was accomplished in the presence of a catalytic amount of tetrabutylammonium bromide (Bu4NBr). Other typical systems using lithium enolate or silyl enolate with catalysts (TiCl4 or Bu4NF) failed to give the desired products. The bromide anion from Bu4NBr coordinates to the tin center in enolate to accelerate the conjugate addition where a five-coordinated tin species was generated. The coordination of the bromide anion significantly raises the HOMO level of tin enolate and enhances its nucleophilicity. The conjugate addition provides the intermediate Michael adduct, which has an ester enolate moiety, and the adduct immediately transforms to α-stannyl γ-ketoester by keto - enol tautomerization. This step contributes to the stabilization of the product system and leads to a thermodynamically favorable reaction course. An ab initio calculation reveals that the activation energy in the reaction using the bromide anion is lower than that of the reaction without using it. The transition state in either reaction course has a linear structure, not a cyclic one. This system can be applied to a variety of tin enolates and α,β-unsaturated carbonyls involving enoates, enones, and unsaturated amides.
Amino derivatives of phenyl alkyl thiophene as inhibitors of bone resorption. Structure-activity relationship
Wierzbicki, Michel,Boussard, Marie-Francoise,Sauveur, Frederic,Kirsch, Gilbert,Sabatini, Massimo,Lesur, Christophe,Trodjman, Charles,Bonnet, Jacqueline
, p. 840 - 849 (2007/10/03)
Metabolism of arachidonic acid through the 5-lipoxygenase (LO) pathway generates compounds that stimulate osteoclastic bone resorption; since LO metabolites might play a role in bone loss due to excessive resorption it was tried to develop a series of antiresorptive agents starting from an already known LO inhibitor. Of the 35 compounds synthesized, 11 strongly inhibited (10 μmol/l) retinoic acid-induced bone resorption in cultured mouse calvariae; they were also tested for their effect on LO activity using rat peritoneal neutrophils, but no correlation could be drawn between inhibition of LO and bone resorption. Other pathways, still to be identified, must therefore be targeted by these compounds even though LO inhibition might contribute to their effects on bone. Two compounds selected for further studies were found active on parathyroid hormone-induced osteolysis, while they had no effect on basal resorption; they must, therefore, act at some key point in the process of activation of osteoclastic resorption. This series of compounds may represent a new way for the treatment of bone loss due to excessive resorption.
