1798-06-7Relevant articles and documents
Ruthenium-catalyzed umpolung carboxylation of hydrazones with CO2
Yan, Si-Shun,Zhu, Lei,Ye, Jian-Heng,Zhang, Zhen,Huang, He,Zeng, Huiying,Li, Chao-Jun,Lan, Yu,Yu, Da-Gang
, p. 4873 - 4878 (2018/06/07)
The first ruthenium-catalyzed umpolung carboxylation of hydrazones with CO2 to generate important aryl acetic acids is reported. Besides aldehyde hydrazones, a variety of ketone hydrazones, which have not been successfully applied in previous umpolung reactions with other reactive electrophiles, also show high reactivity and selectivity under mild conditions. Moreover, this operationally simple protocol features good functional group tolerance, is readily scalable, and offers easy derivation of important structures, including bioactive felbinac and adiphenine. Computational studies reveal that this umpolung reaction proceeds through the generation of a Ru-nitrenoid followed by concerted [4 + 2] cycloaddition with CO2.
Synthesis and biological evaluation of a novel class of rofecoxib analogues as dual inhibitors of cyclooxygenases (COXs) and lipoxygenases (LOXs)
Chen, Qiao-Hong,Praveen Rao,Knaus, Edward E.
, p. 7898 - 7909 (2007/10/03)
A group of 4-(4-methanesulfonylphenyl)-3-phenyl-2(5H)furanones possessing an acetyl, 3-oxobut-1-ynyl, [hydroxyl(or alkoxy)imino]alkyl, [hydroxyl(or alkoxy)imino]alkynyl, and N-alkoxy(or N-phenoxy)carbonyl-N-hydroxy-N-ethylamino substituents at the para-position of the C-3 phenyl ring of rofecoxib were synthesized. This group of compounds was designed for evaluation as dual inhibitors of cyclooxygenases (COXs) and lipoxygenases (LOXs) that exhibit in vivo anti-inflammatory and analgesic activities. In vitro COX-1/COX-2, and 5-LOX/15-LOX, isozyme inhibition structure-activity relationships identified 3-[4-(1-hydroxyimino)ethylphenyl]-4-(4-methanesulfonylphenyl)-2(5H)furanone (17a) having an optimal combination of COX-2 (COX-2 IC50 = 1.4 μM; COX-2 SI > 71), and 5-LOX and 15 LOX (5-LOX IC50 = 0.28 μM; 15-LOX IC50 = 0.32 μM), inhibitory effects. It was also discovered that 3-[4-(3-hydroxyiminobut-1-ynyl)phenyl]-4-(4-methanesulfonylphenyl)-2(5H)furanone (18a) possesses dual COX-2 (IC50 = 2.7 μM) and 5-LOX (IC50 = 0.30 μM) inhibitor actions. Further in vivo studies employing a rat carrageenan-induced paw edema model showed that the oxime compounds (17a, 18a) were more potent anti-inflammatory agents than the 5-LOX inhibitor caffeic acid, and 15-LOX inhibitor nordihydroguaiaretic acid (NDGA), but less potent than the selective COX-2 inhibitor celecoxib. The results of this investigation showed that incorporation of a para-oxime moiety on the C-3 phenyl ring of rofecoxib provides a suitable template for the design of dual inhibitors of the COX and LOX enzymes.
Substituent Effects in the Fluorination-Rearrangement of 1,1-Diarylethenes with Aryliodine(III) Difluorides
Patrick, Timothy B.,Scheibel, Jeffrey J.,Hall, Warren E.,Lee, Young H.
, p. 4492 - 4494 (2007/10/02)
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