Synthesis of Coumarins via Pd-Catalyzed Oxidative Cyclocarbonylation of 2-Vinylphenols
摘要:
Palladium-catalyzed oxidative cyclocarbonylation of 2-vinylphenols constitutes a simple, direct method for the synthesis of coumarins. The reaction conditions, employing low pressures of CO, and air or 1,4- benzoquinone as the oxidant, are attractive in terms of environmental considerations and operational simplicity. Coumarins with a variety of functional groups were prepared in yields up to 85%.
Synthesis and structure–activity relationships of novel IKK-β inhibitors. Part 3: Orally active anti-inflammatory agents
摘要:
A series of 2-amino-3-cyano-4-alkyl-6-(2-hydroxyphenyl)pyridine derivatives was synthesized and evaluated as IkappaB kinase beta (IKK-beta) inhibitors. Modification of a novel IKK-beta inhibitor 1 (IKK-beta IC50 = 1500 nM, Cell IC50 = 8000 nM) at the 4-phenyl ring and 6-phenol group on the pyridine core ring resulted in a marked increased in biological activities. An optimized compound, 2-amino-6-[2-(cyclopropylmethoxy)-6-hydroxyphenyl]-4-piperidin-4-yl nicotinonitrile, exhibited excellent in vitro profiles (IKK-beta IC50 = 8.5 nM, Cell IC50 = 60 nM) and a strong oral efficacy in in vivo anti-inflammatory assays (significant effects at 1 mg/kg, po in arachidonic acid-induced ear edema model in mice). (C) 2004 Elsevier Ltd. All rights reserved.
Benzoxazine derivatives are useful building blocks and display various biological activities. We serendipitously discovered and subsequently developed a new one pot method for the synthesis of 2-(dimethyl amino)/2-morpholino/2- (piperidin-1-yl)-4H-benzo[e][1,3]oxazin-4-ones from corresponding substituted 2,2-diazidobenzofuran 3(2H) - ones and N-formyl dimethyl amine (DMF)/N-formylmorpholine/N-formylpiperidine
Ruthenium‐catalyzed selective monoalkenylation of ortho CO or CN bonds of aromatic ketones was achieved. The reaction allowed the direct comparison of the relative reactivities of the cleavage of different carbon‐heteroatom bonds, thus suggesting an unconventional chemoselectivity, where smaller, more‐electron‐donating groups are more easily cleaved. Selective monofunctionalization of CO bonds in
Es wird gezeigt, dass man durch Kondensation von basisch substituierten Estern mit o-Oxy-acylphenonen und Ringschluss der entstandenen 1,3-Diketone zu Chromonen gelangt, die in 2-Stellung basisch substituiert sind. Die Synthese liess sich auch mit N-acetylierten Estern durchführen.
A Divergent and Selective Synthesis of Isomeric Benzoxazoles from a Single N–Cl Imine
作者:Cheng-yi Chen、Teresa Andreani、Hongmei Li
DOI:10.1021/ol202844c
日期:2011.12.2
divergent and regioselective synthesis of either 3-substituted benzisoxazoles or 2-substituted benzoxazoles from readily accessible ortho-hydroxyaryl N–H ketimines is described. The reaction proceeds in two distinct pathways through a common N–Cl imine intermediate: (a) N–O bond formation to form benzisoxazole under anhydrous conditions and (b) NaOCl mediated Beckmann-type rearrangement to form benzoxazole
The first enantioselective chiral phosphoricacid-catalyzedtransferhydrogenation of unprotected ortho-hydroxyaryl alkyl N−H ketimines using Hantszch di-tert-butyl ester as a reductant is reported. A variety of ortho-hydroxybenzylamines were obtained in good to excellent yields and enantiomeric excesses.