Palladium-Catalyzed Asymmetric Conjugate Addition of Arylboronic Acids to Heterocyclic Acceptors
作者:Jeffrey C. Holder、Alexander N. Marziale、Michele Gatti、Bin Mao、Brian M. Stoltz
DOI:10.1002/chem.201203643
日期:2013.1.2
Flava Flavanone: Asymmetricconjugateadditions to chromones and 4‐quinolones are reported utilizing a single catalyst system formed in situ from Pd(OCOCF3)2 and (S)‐tBuPyOX. Notably, these reactions are performed in wet solvent under ambient atmosphere, and employ readily available arylboronicacids as the nucleophile, thus providing ready access to these asymmetric heterocycles (see scheme).
DBU-catalyzed one-pot cascade reaction of propargylamines and water for the synthesis of flavanones has been developed. This process proceeds via a sequence of 1,4-conjugate addition of water to alkynyl o-quinone methide (o-AQM), followed by the alkyne–allene isomerization and subsequent intramolecular oxa-Michael addition. This strategy provides a convenient method for accessing a broad range of flavanones
flavanones, which included polycyclic aromatic and heterocyclic rings, were readily synthesized via oxa-Michael addition from the corresponding hydroxychalcones with a catalytic amount of aqueous cesium fluoride solution under mild conditions. This method could be applied to the scalable synthesis of eriodictyol as a known potent inhibitor of the SARS-CoV-2 spike protein.
SAR studies of o-hydroxychalcones and their cyclized analogs and study them as novel inhibitors of cathepsin B and cathepsin H
作者:N. Raghav、S. Garg
DOI:10.1016/j.ejps.2014.04.006
日期:2014.8
potent inhibitors among the three series were nitro substitutedcompounds 1g, 2g and 3g with Ki values of approximately 6.18x10(-8) M, 4.8x10(-7) M and 7.85x10(-7) M for cathepsin B and Ki values of approximately 2.8x10(-7) M, 31.8x10(-6) M and 33.7x10(-6) M for cathepsin H, respectively. The relationship between chalcone, flavanones and flavone structures interpreted by docking studies on cathepsin
An efficient and “green” catalytic conversion of 2'-hydroxychalcones to flavanones in 15 min in the presence of a simple amino acid and a base at room temperature is reported. Liquiritigenin was also efficiently synthesised under these conditions.