A base-controlled chemoselective transfer hydrogenation of α,β-unsaturated ketones catalyzed by [IrCp*Cl<sub>2</sub>]<sub>2</sub> with 2-propanol
作者:Shu-jie Chen、Guo-ping Lu、Chun Cai
DOI:10.1039/c5ra00484e
日期:——
A simple homogeneous catalyst system based on commercially available [IrCp*Cl2]2 has been developed for the transfer hydrogenation of α,β-unsaturated ketones.
Dialkyl Phosphite-Initiated Cyclopropanation of α,β-Unsaturated Ketones Using α-Ketoesters or Isatin Derivatives
作者:Deng Yin、Hui Liu、Chong-Dao Lu、Yan-Jun Xu
DOI:10.1021/acs.joc.6b03009
日期:2017.3.17
cyclopropanation of α,β-unsaturatedketones using α-ketoesters or isatin derivatives is reported. The cyclopropanation reaction occurs via a cascade transformation that starts with addition of deprotonated dialkyl phosphite to the keto groups of α-ketoesters or isatin derivatives, followed by [1,2]-phosphonate/phosphate rearrangement to generate α-phosphonyloxyenolate intermediates, which are trapped by α,β-unsaturated
Highly enantioselective Michael addition of diethyl malonate to chalcones catalyzed by cinchona alkaloids-derivatived bifunctional tertiary amine-thioureas bearing multiple hydrogen-bonding donors
作者:Yulong Liu、Xie Wang、Xiaoyun Wang、Wei He
DOI:10.1039/c4ob00203b
日期:——
Chalcones are still challenge substrates in Michael reactions, and only limited success has been achieved. This work describes a highlyenantioselectiveMichaeladdition of diethyl malonate with chalcones catalyzed by cinchona alkaloids-derivatived bifunctional tertiary amine-thioureasbearingmultiplehydrogen-bondingdonors.
catalysts for Henry condensation. Here, the catalytic activity of Mets7‐Cu(I) complex in Michael addition reactions has been evaluated. Furthermore, His7 peptide, in which Met residues have been substituted with His ones, was also prepared. This substitution allowed His7 to coordinate Cu (II), with the obtainment of a stable turn conformation as evicted by CD experiments. His7‐Cu (II) proved also to be
Mets7是存在于 hCtr-1 转运蛋白中的富含甲硫氨酸的基序,参与铜细胞运输。它结合 Cu(I) 的能力最近被用来开发用于亨利缩合的金属肽催化剂。在这里,已经评估了Mets7-Cu(I) 配合物在迈克尔加成反应中的催化活性。此外,还制备了其中Met残基已被His残基取代的His7肽。这种取代允许His7与 Cu (II) 配位,获得了稳定的转角构象,如 CD 实验所驱逐。在加成反应中,His7-Cu (II)也被证明是比Mets7-Cu(I)更好的催化剂。特别是,当底物是 (E )-1-苯基-3-(吡啶-2-基)prop-2-en-1-one,观察到71%的转化率和58%的ee转化率。
Inhibition of LPS-stimulated ROS production by fluorinated and hydroxylated chalcones in RAW 264.7 macrophages with structure-activity relationship study
作者:Ganesh Bist、Nirmala Tilija Pun、Til Bahadur Thapa Magar、Aarajana Shrestha、Hye Jin Oh、Amrita Khakurel、Pil-Hoon Park、Eung-Seok Lee
DOI:10.1016/j.bmcl.2017.01.061
日期:2017.3
previous fluorinated and/or hydroxylated chalcones studies, thirty-six compounds were designed as phenyl or hydroxyphenyl bearing fluoro, trifluoromethyl or trifluoromethoxy phenyl propenones and synthesized by applying modified Claisen-Schmidt condensation reaction as a single step. Inhibitory effects of the synthesized compounds on ROSproductionstimulated by LPS in RAW264.7macrophage were evaluated