Tetrasubstituted Furans by Nucleophile-Induced Cleavage of Carbonyl Ylide–DMAD Cycloadducts
作者:Gerhard Maas、Matthias Dobesch、Julian Greiner
DOI:10.1055/s-0040-1707897
日期:——
Abstract Compounds incorporating a 4-aza-8-oxabicyclo[3.2.1]oct-6-en-2-one moiety, which were prepared by a tandem carbenoid carbonyl ylide cyclization/[3+2]-cycloaddition reaction from ethyl 2-diazo-3-oxo-4-phthalimidobutanoates, undergo a nucleophile-induced two-bond ring cleavage when treated with protic heteronucleophiles. In this manner, tetrasubstituted furantricarboxylates, tethered with α-amino
N‐Terminal‐Specific Dual Modification of Peptides through Copper‐Catalyzed [3+2] Cycloaddition
作者:Haruka Machida、Kazuya Kanemoto
DOI:10.1002/anie.202320012
日期:2024.3.18
Site‐specific introduction of multiple components into peptides is greatly needed for the preparation of densely functionalized and structurally uniform peptides. In this regard, N‐terminal‐specific peptide modification is attractive, but it can be difficult due to the presence of highly nucleophilic lysine ϵ‐amine. In this work, we developed a method for the N‐terminal‐specific dual modification of peptides through a three‐component [3+2] cycloaddition with aldehydes and maleimides under mild copper catalysis. This approach enables exclusive functionalization at the glycine N‐terminus of iminopeptides, regardless of the presence of lysine ϵ‐amine, thus affording the cycloadducts in excellent yields. Tolerating a broad range of functional groups and molecules, the present method provides the opportunity to rapidly construct doubly functionalized peptides using readily accessible aldehyde and maleimide modules.
Methionine-enabled peptide modification through late-stage Pd-catalyzed β-C(sp3)–H olefination/cyclization