by limited access to appropriate substrate surrogates. We present a step-economic synthetic access to biomimetic β-ketopolyene thioesters that is based on an Ir-catalyzed reductive Horner–Wadsworth–Emmonsolefination. New β-ketotriene and pentaenethioates of pantetheine and N-acetylcysteamine were exemplarily synthesized via short and concise routes. The usefulness of these compounds was demonstrated
Oxidative Formation of Disulfide Bonds by a Chemiluminescent 1,2-Dioxetane under Mild Conditions
作者:Caroline S. Sauer、Johannes Köckenberger、Markus R. Heinrich
DOI:10.1021/acs.joc.0c00569
日期:2020.7.17
The oxidation of alkyl thiols to disulfides has been achieved under mild conditions using a chemiluminescent 1,2-dioxetane as a stoichiometric oxidant. Besides the mild and biocompatible reaction conditions, this approach offers the possibility to monitor the presence of thiols through oxidation and chemiluminescence of the remaining dioxetane.
Characterization of the promiscuous <i>N</i>-acyl CoA transferase, LgoC, in legonoxamine biosynthesis
作者:Fleurdeliz Maglangit、Saad Alrashdi、Justine Renault、Laurent Trembleau、Catherine Victoria、Ming Him Tong、Shan Wang、Kwaku Kyeremeh、Hai Deng
DOI:10.1039/d0ob00320d
日期:——
More than 500 siderophores are known to date, but only three were identified to be aryl-containing hydroxamate siderophores, legonoxamines A and B from Streptomyces sp. MA37, and aryl ferrioxamine 2 from Micrococcus luteus KLE1011.
Lipophilic analogs of sparsomycin as strong inhibitors of protein synthesis and tumor growth: a structure-activity relationship study
作者:Leon A. G. M. Van den Broek、Ester Lazaro、Zbigniew Zylicz、Paul J. Fennis、Frank A. N. Missler、Peter Lelieveld、Marina Garzotto、D. J. Theo Wagener、Juan P. G. Ballesta、Harry C. J. Ottenheijm
DOI:10.1021/jm00128a051
日期:1989.8
Fourteen derivatives of sparsomycin (1) were synthesized. Six of them were prepared following a novel synthetic route starting from the L-amino acid alanine. Some physicochemicalproperties, viz. lipophilicity and water solubility, of selected derivatives were measured. The biological activity was tested in vitro in cell-free protein synthesis inhibition assays, in bacterial and tumor cell growth inhibition
Synthesis of Reversible Shell Crosslinked Nanostructures
申请人:McCormick Charles L.
公开号:US20080234391A1
公开(公告)日:2008-09-25
In one aspect, the present invention is directed to a thermally responsive AB diblock copolymer prepared by RAFT polymerization wherein the diblock copolymer comprises poly(N-(3-aminopropyl)methacrylamide hydrochloride)-block-(N-isopropylacrylamide). Nanostructures of the thermally responsive diblock copolymer are formed by molecularly dissolving the diblock copolymer in aqueous solution at room temperature; and increasing the solution temperature to form nanostructures, for example vesicles or micelles. The first RAFT polymerization of an unprotected amino acid based monomer directly in water is also disclosed. The present invention also provides a method of forming shell cross-linked vesicles by adding a RAFT synthesized anionic homopolymer to a solution of the thermally responsive diblock copolymer. A method of forming interpolyelectrolyte complexed micelles or vesicles is also disclosed, the method comprising preparing by sequential aqueous RAFT polymerization a block copolymer comprised of N,N,-dimethyl acrylamide (DMA), N-acryloyl alanine (AAL) and N-isopropyl acrylamide (NIPAM); dissolving the block copolymers into aqueous solution; raising the solution temperature above the lower critical solution temperature of the NIPAM block; allowing the micelle solution to equilibrate; adjusting the pH of the solution to about 5; adding a cationic polymer to the solution; and stirring the solution. The reaction is readily reversed by the addition of a salt solution. In another aspect of the invention a reversible shell cross-linked micelle of a triblock copolymer cross-linked with cystamine is disclosed where a cleaving agent can be added to cleave the micelles. The reaction can be reversed with the addition of tris(2-carboxyethyl)phosphine or dithiothreitol.