A Unified Catalytic Asymmetric (4+1) and (5+1) Annulation Strategy to Access Chiral Spirooxindole‐Fused Oxacycles
作者:Min Gao、Yanshu Luo、Qianlan Xu、Yukun Zhao、Xiangnan Gong、Yuanzhi Xia、Lin Hu
DOI:10.1002/anie.202105282
日期:2021.9
A unified catalyticasymmetric (N+1) (N=4, 5) annulation reaction of oxindoles with bifunctional peroxides has been achieved in the presence of a chiral phase-transfer catalyst (PTC). This general strategy utilizes peroxides as unique bielectrophilic four- or five-atom synthons to participate in the C−C and the subsequent umpolung C−O bond-forming reactions with one-carbon unit nucleophiles, thus providing
在手性相转移催化剂 (PTC) 的存在下,已经实现了羟吲哚与双官能过氧化物的统一催化不对称 ( N +1) ( N =4, 5) 环化反应。这种通用策略利用过氧化物作为独特的双亲电四原子或五原子合成子参与 C−C 和随后与单碳单元亲核试剂的 umpolung C−O 键形成反应,从而提供了一种独特的方法来获得有价值的手性螺吲哚-四氢呋喃和-四氢吡喃在温和条件下具有良好的产率和高对映选择性。进行 DFT 计算以合理化高对映选择性的起源。还证明了所得产物的克级合成和合成效用。
Synthesis of Yb Complexes with Amino-Acid-Armed Ligands for Direct Asymmetric Tandem Aldol Reduction Reactions
amino acids. In this article, the asymmetric aldol-reduction reaction leading to 1,3-diols (known as the aldol–Tishchenko reaction) has been performed with an elaborated family of ligands. This unique tandem reaction was catalysed by chiral Yb complexes that promote both the aldolreaction of unactivated carbonyl compounds and the Evans–Tishchenko reduction of the aldol intermediates. 1,3-anti-Diols with
Defining the Structural Parameters That Confer Anticonvulsant Activity by the Site-by-Site Modification of (<i>R</i>)-<i>N</i>′-Benzyl 2-Amino-3-methylbutanamide
作者:Amber M. King、Marc De Ryck、Rafal Kaminski、Anne Valade、James P. Stables、Harold Kohn
DOI:10.1021/jm200760a
日期:2011.10.13
FAAs, a substituted heteroatom one atom removed from the C(2)-center was optimal. Previously in this issue, we showed that PAAD activity was dependent upon the electronicproperties of the 4′-N′-benzylamide substituent, while FAA activity was insensitive to electronic changes at this site. In this study, we prepared analogues of (R)-N′-benzyl 2-amino-3-methylbutanamide to identify the structural components
Synthetic antineoplastic agents derived from dolastatin 15 and methods of making same
申请人:Arizona Board of Regents, acting for and on behalf of Arizona State University
公开号:US06686445B1
公开(公告)日:2004-02-03
A composition of matter, denominated herein as 12a-r, having the structural formula set forth below:
wherein R is selected from the group consisting of:
a) R=NHPh;
b) R=NHCH2Ph;
c) R=NH(CH2)2Ph;
d) R=NH(CH2)2‘-4-F-Ph;
e) R=NH(CH2)2-4-Cl-Ph;
f) R=NH(CH2)2-3-Cl-Ph;
g) R=NH(CH2)2-2-Cl-Ph;
h) R=NH(CH2)2-4-Br-Ph;
i) R=NH(CH2)2-4-NO2-Ph;
j) R=NH(CH2)2-3,4-(CH3O)2Ph;
k) R=NH(CH2)2-2-pyridine;
l) R=NH(CH2)3Ph;
m) R=L-Phe-OCH3;
n) R=L-Met-OCH3;
o) R=L-Pro-OCH3;
p) R=NH-2-thiazolyl;
q) R=NH-2-benzothiazolyl;
r) R=NH-3-quinolyl;
and methods of making these compounds 12a-r.