Synthesis of a Hydroxyethylene Isostere of the Tripeptide Arg-Gly-Leu via a Convergent Acyl-like Radical Addition Strategy
作者:Christina M. Jensen、Karl B. Lindsay、Peter Andreasen、Troels Skrydstrup
DOI:10.1021/jo0505775
日期:2005.9.1
important fragment of a novel cyclic-peptide-based uPA inhibitor, was synthesized in few steps employing as the key step a samarium diiodide promoted coupling of either the 4-thiopyridyl ester of Nα-Fmoc- or Nα-Cbz-protected l-ornithine with the N-acryloyl derivative of l-leucine methyl ester. Epimerization under the coupling conditions at the chiral center in the α-position to the ketone was demonstrated
functionalized acyclic chiral pyrroloamide compounds were synthesized by a simple and robust process involving the creation of a C-C bond between unprotected pyrroles and acyclic chiral acrylamides using Lewis acids. This alkylation reaction using Michael acceptors has been optimized, allowing us to obtain channel selective access to monoalkylated or dialkylated pyrroles, in good yields. Di- and tripeptide deriving
Studies in the Synthesis and Reactivity of New Chiral 1-[(Trialkylsilyl)-methyl]propenamides
作者:Samir BouzBouz
DOI:10.1055/s-0030-1260960
日期:2011.8
A very simple sequence of reactions such as cross-metathesis using two catalysts and allylation to give the chiral hydroxyamide is described.
介绍了一种非常简单的反应序列,如使用两种催化剂的交叉易位反应和烯丙基化反应,以得到手性羟基酰胺。
Can Decarbonylation of Acyl Radicals Be Overcome in Radical Addition Reactions? En Route to a Solution Employing <i>N</i>-Acyl Oxazolidinones and SmI<sub>2</sub>/H<sub>2</sub>O
作者:Christina M. Jensen、Karl B. Lindsay、Rolf H. Taaning、Jakob Karaffa、Anna Mette Hansen、Troels Skrydstrup
DOI:10.1021/ja050420u
日期:2005.5.1
The application of acyl radicals in radical addition reactions in the absence of a CO atmosphere is generally limited to aryl or alpha-unsubstituted alkyl acyl radicals due to competing decarbonylations where the rate constant for this degradation process surpasses 104 s-1. In this work, a potential solution to avoid the problem of decarbonylations is presented employing N-acyl oxazolidinones which
Site-Selective C–O Bond Editing of Unprotected Saccharides
作者:Guanjie Wang、Chang Chin Ho、Zhixu Zhou、Yong-Jia Hao、Jie Lv、Jiamiao Jin、Zhichao Jin、Yonggui Robin Chi
DOI:10.1021/jacs.3c10963
日期:2024.1.10
catalytic site-selective installation of a photoredox active carboxylic ester group to a specific hydroxyl unit of an unprotected sugar. The second step, namely, “editing”, features a C–O bondcleavage to form a carbon radical intermediate that undergoes further transformations such as C–H and C–C bond formations. Our strategy constitutes the most effective and shortest route in direct transformation and modification