71501-17-2Relevant academic research and scientific papers
A metal-free desulfurizing radical reductive C-C coupling of thiols and alkenes
Qin, Qixue,Wang, Weijing,Zhang, Cheng,Song, Song,Jiao, Ning
supporting information, p. 10583 - 10586 (2019/09/06)
An intermolecular reductive C-C coupling of electrophilic alkyl radicals and alkenes has been developed. Thiols were used as both hydrogen-donating reagents and alkyl radical precursors in the presence of triethyl phosphite and radical initiator. A wide range of alkenes, including styrenes, and aliphatic olefins were well tolerated in this transformation. Mechanistic studies indicated that a phosphite promoted radical desulfurization of thiols to access electrophilic alkyl radicals and a radical chain propagation process may be involved in this transformation.
Metal-free visible light photoredox enables generation of carbyne equivalents via phosphonium ylide C-H activation
Das, Mrinmoy,Vu, Minh Duy,Zhang, Qi,Liu, Xue-Wei
, p. 1687 - 1691 (2019/02/14)
Carbyne, an interesting synthetic intermediate, has recently been generated from hypervalent iodine precursors via photoredox catalysis. Given the underexplored chemistry of carbyne, due to the paucity of carbyne sources, we are intrigued to discover a new source for this reactive species from classical reagents-phosphonium ylides. Our novel strategy employing phosphonium ylides in an olefin hydrocarbonation reaction features a facile approach for constructing carbon-carbon bonds through metal-free and benign reaction conditions. Moreover, the hydrocarbonation products were delivered in a highly regioselective manner.
Cross-Coupling of Amides with Alkylboranes via Nickel-Catalyzed C-N Bond Cleavage
Liu, Xiangqian,Hsiao, Chien-Chi,Guo, Lin,Rueping, Magnus
supporting information, p. 2976 - 2979 (2018/05/28)
A protocol for the nickel-catalyzed alkylation of amides was established. The use of alkylboranes as nucleophilic partners allowed the use of mild reaction conditions and compatibility of various functional groups with respect to both coupling partners. The catalytic alkylation proceeded selectively at the amides in the presence of other functional groups as well as other carboxylic acid derived moieties.
Ligand-Controlled Chemoselective C(acyl)-O Bond vs C(aryl)-C Bond Activation of Aromatic Esters in Nickel Catalyzed C(sp2)-C(sp3) Cross-Couplings
Chatupheeraphat, Adisak,Liao, Hsuan-Hung,Srimontree, Watchara,Guo, Lin,Minenkov, Yury,Poater, Albert,Cavallo, Luigi,Rueping, Magnus
, p. 3724 - 3735 (2018/03/21)
A ligand-controlled and site-selective nickel catalyzed Suzuki-Miyaura cross-coupling reaction with aromatic esters and alkyl organoboron reagents as coupling partners was developed. This methodology provides a facile route for C(sp2)-C(sp3) bond formation in a straightforward fashion by successful suppression of the undesired β-hydride elimination process. By simply switching the phosphorus ligand, the ester substrates are converted into the alkylated arenes and ketone products, respectively. The utility of this newly developed protocol was demonstrated by its wide substrate scope, broad functional group tolerance and application in the synthesis of key intermediates for the synthesis of bioactive compounds. DFT studies on the oxidative addition step helped rationalizing this intriguing reaction chemoselectivity: whereas nickel complexes with bidentate ligands favor the C(aryl)-C bond cleavage in the oxidative addition step leading to the alkylated product via a decarbonylative process, nickel complexes with monodentate phosphorus ligands favor activation of the C(acyl)-O bond, which later generates the ketone product.
Di- and trivalent small molecule selectin inhibitors
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, (2008/06/13)
The present invention provides compounds having structure (II), and the pharmaceutically acceptable salts, esters, amides and prodrugs thereof.
Novel synthetic inhibitors of selectin-mediated cell adhesion: Synthesis of 1,6-bis[3-(3-carboxymethylphenyl)-4-(2-α-D-mannopyranosyloxy)phenyl] hexane (TBC1269)
Kogan, Timothy P.,Dupré, Brian,Bui, Huong,McAbee, Kathy L.,Kassir, Jamal M.,Scott, Ian L.,Hu, Xin,Vanderslice, Peter,Beck, Pamela J.,Dixon, Richard A. F.
, p. 1099 - 1111 (2007/10/03)
Reports of a high-affinity ligand for E-selectin, sialyl di-Lewis(x) (sLe(x)Le(x), 1), motivated us to incorporate modifications to previously reported biphenyl-based inhibitors that would provide additional interactions with the protein. These compounds were assayed for the ability to inhibit the binding of sialyl Lewis(x) (sLe(x), 2) bearing HL-60 cells to E-, P-, and L- selectin fusion proteins. We report that dimeric or trimeric compounds containing multiple components of simple nonoligosaccharide selectin antagonists inhibit sLe(x)-dependent binding with significantly enhanced potency over the monomeric compound. The enhanced potency is consistent with additional binding interactions within a single selectin lectin domain; however, multivalent interaction with multiple lectin domains as a possible alternative cannot be ruled out. Compound 15e (TBC1269) showed optimal in vitro activity from this class of antagonists and is currently under development for use in the treatment of asthma.
