5912-84-5Relevant academic research and scientific papers
Olefin functionalization/isomerization enables stereoselective alkene synthesis
Gutierrez, Osvaldo,Koh, Ming Joo,Liu, Chen-Fei,Martin, Robert T.,Wang, Hongyu,Zhao, Haonan
, p. 674 - 683 (2021/08/06)
Despite tremendous efforts aimed at devising methods for stereoselective alkene synthesis, critical challenges are yet to be addressed. Direct access to a diverse range of 1-aryl(boryl)-1-methyl-functionalized tri- and tetrasubstituted trans alkenes, entities that are prevalent in many important molecules, through a catalytic manifold from readily available α-olefin substrates remains elusive. Here, we demonstrate that catalytic amounts of a non-precious N-heterocyclic carbene–Ni(I) complex in conjunction with a sterically bulky base promote site- and trans-selective union of monosubstituted olefins with a wide array of electrophilic reagents to deliver tri- and tetrasubstituted alkenes in up to 92% yield and >98% regio- and stereoselectivity. The protocol is amenable to the preparation of carbon- and heteroatom-substituted C=C bonds, providing distinct advantages over existing transformations. Utility is highlighted through concise stereoselective synthesis of biologically active compounds. [Figure not available: see fulltext.].
Diaryl-dithiolanes and -isothiazoles: COX-1/COX-2 and 5-LOX-inhibitory, {radical dot}OH scavenging and anti-adhesive activities
Scholz, Michael,Ulbrich, Holger K.,Soehnlein, Oliver,Lindbom, Lennart,Mattern, Andreas,Dannhardt, Gerd
supporting information; experimental part, p. 558 - 568 (2009/08/07)
Three series of non-steroidal anti-inflammatory drugs (NSAIDs) inhibiting the cyclooxygenase/5-lipoxygenase (COX/5-LOX) pathways as such as formation of hydroxyl radicals and adhesion were prepared: 4,5-diaryl isothiazoles, 4,5-diaryl 3H-1,2-dithiole-3-thiones and 4,5-diaryl 3H-1,2-dithiole-3-ones. The aim of the present study was to develop substances which can intervene into the inflammatory processes via different mechanisms of action as multiple target non-steroidal anti-inflammatory drugs (MTNSAIDs) with increased anti-inflammatory potential. The current lead 11a was evaluated in COX-1/2, 5-LOX and {radical dot}OH scavenging in vitro assays and in a static adhesion assay where it proved to inhibit adhesion. Moreover, 11a treatment attenuated expression of macrophage adhesion molecule-1 (Mac-1) on extravasated polymorphonuclear leukocytes (PMNs) which indicates that the activation was reduced. The assays used are predictive for the in vivo efficacy of test compounds as shown for 11a in a peritonitis model of acute inflammation in mice. Thus, the novel 5-LOX/COX and {radical dot}OH inhibitor 11a possesses anti-inflammatory activity that, in addition to COX/5-LOX inhibition, implicates effects on leukocyte-endothelial interactions.
Highly regio- and stereoselective palladium(0)-catalyzed addition of organoboronic acids with 1,2-allenic sulfones, sulfoxides, or alkyl- or aryl-substituted allenes in the presence of acetic acid: An efficient synthesis of E-alkenes
Guo, Hao,Ma, Shengming
, p. 2731 - 2745 (2008/03/13)
Two sets of reaction conditions were established to enable the palladium(0)-catalyzed addition of organoboronic acids with 1,2-allenic sulfones, sulfoxides, or alkyl- or aryl-substituted allenes in the presence of acetic acid. This reaction provides a new
MARSUPOL: A NOVEL ISOFLAVONOID GLYCOL FROM PTEROCARPUS MARSUPIUM
Rao, A. V. Subba,Mathew, James
, p. 1837 - 1838 (2007/10/02)
The isolation, structure and synthesis of 4,4'-dihydroxy-α-methylhydrobenzoin are described.This is the first report of a naturally occurring hydrobenzoin.Key Word Index - Pterocarpus marsupium; Leguminosae; heartwood; isoflavonoid; α-methylhydrobenzoin; marsupol.
