Indium-Catalyzed Amide Allylation of N-Carbonyl Imides: Formation of Azaspiro-γ-lactones via Ring Opening–Reclosure
摘要:
A novel and facile synthesis of azaspiro-gamma-lactones with a methylene-lactam framework from N-carbonyl imides is described. Mechanistic investigations provide evidence for a two-step reaction process involving ZnCl2-promoted addition of beta-amido allylindium species followed by an unexpectedly molecular-sieves-mediated ring opening-reclosure concomitantly with the loss of an N-carbonyl unit.
This communication describes the utility of β-amido allylboronate as a nucleophile in the catalytic amide allylation of N-carbonyl imides. The reaction of the imide substrates with the boronates has been accomplished by using catalytic zinc bromide and basic additives (ethanol, potassium carbonate and 18-crown 6-ether), affording azaspiro-γ-lactones through a ring opening-reclosure process with yields
with cyclic imino esters catalyzed by a bifunctional chiral tertiary amine has been developed, which provides an efficient access to optically active β-position functionalized pyrrolidin-2-one derivatives in both high yield and enantioselectivity (up to 78% yield and 95 : 5 er). This is the first catalytic method to access chiral β-functionalized pyrrolidin-2-one via a direct organocatalytic approach
[EN] CAMPTOTHECIN DERIVATIVES<br/>[FR] DÉRIVÉS DE CAMPTOTHÉCINE
申请人:IMMUNOGEN INC
公开号:WO2020219287A1
公开(公告)日:2020-10-29
Disclosed herein are novel cytotoxic compounds, and cytotoxic conjugates comprising these cytotoxic compounds and cell-binding agents. More specifically, this disclosure relates to novel camptothecin derivatives thereof, intermediates thereof, conjugates thereof, and pharmaceutically acceptable salts thereof, which are useful as medicaments, in particular as anti-proliferative agents (anticancer agents).
A Practical and Robust Zwitterionic Cooperative Lewis Acid/Acetate/Benzimidazolium Catalyst for Direct 1,4‐Additions
作者:Andreas C. Hans、Patrick M. Becker、Johanna Haußmann、Simon Suhr、Daniel M. Wanner、Vera Lederer、Felix Willig、Wolfgang Frey、Biprajit Sarkar、Johannes Kästner、René Peters
DOI:10.1002/anie.202217519
日期:2023.3.20
Intramolecular cooperation of CuII, coordinated acetate and a benzimidazolium unit in the catalyst periphery allows for unprecedented catalyst productivity and high stereocontrol in direct 1,4-additions to maleimides and a number of other Michael acceptors. Next to the sophisticated activation principle, the catalyst is readily prepared and has robust reactivity. Moreover, it is shown to be reusable
Cu II、协调的乙酸盐和催化剂外围的苯并咪唑单元的分子内合作允许在马来酰亚胺和许多其他迈克尔受体的直接 1,4-加成中实现前所未有的催化剂生产率和高立体控制。除了复杂的活化原理外,该催化剂易于制备并具有强大的反应活性。此外,它被证明可以多次重复使用。
Thermostable glucose biosensors and uses thereof
申请人:Duke University
公开号:US11402384B2
公开(公告)日:2022-08-02
The present subject matter provides glucose biosensors as well as compositions, devices, and methods comprising such biosensors.