Silver acetate-assisted formation of amides from acyl chlorides
作者:A. Leggio、E.L. Belsito、M.L. Di Gioia、V. Leotta、E. Romio、C. Siciliano、A. Liguori
DOI:10.1016/j.tetlet.2014.11.067
日期:2015.1
acid chlorides to give amides is disclosed. Reactions are carried out in the presence of silver acetate in non-aqueous environments under heterogeneous phase conditions. Amides are easily recovered in very good to excellent yields and without racemization. The approach is successful in forming peptide bonds starting from N-(4-nitrobenzenesulfonyl)-amino acid chlorides and allows the formation of dipeptides
were allowed to react with a nucleophile (silyl enol ether or allyltributyltin) in the presence of an acyl chloride derivedfrom (S)-alanine to afford the 1,2-addition products in good chemical yields and high stereoselectivity. The bromo groups were readily removed by a reduction process in which the double bond at C3–C4 was also reduced. Thus the reaction system provided a general method to synthesize
N-Nosyl-α-amino acids in solution phase peptide synthesis
作者:Antonella Leggio、Maria Luisa Di Gioia、Francesca Perri、Angelo Liguori
DOI:10.1016/j.tet.2007.05.121
日期:2007.8
excellent purity of the final products. The described strategy allows the preparation of short peptide sequences keeping the chiral integrity of amino acid precursors. Compatibility of nosyl group with the side-chain protecting groups used in Fmoc-based strategy is demonstrated. The method here presented is an alternative strategy that could provide advantages for future peptide synthesis.
Synthesis and anticancer activity of the proposed structure of caldoramide, an N-peptidyltetramate from the cyanobacterium Caldora penicillata
作者:Anja Wunder、Matthias Rothemund、Rainer Schobert
DOI:10.1016/j.tet.2018.04.004
日期:2018.9
The structure proposed in the literature for caldoramide, a formal pentapeptide metabolite of the marine cyanobacterium Caldora penicillata, was synthesised in 12 steps and 16% yield (longest linear sequence from isoleucine) following the strategy of a stepwise consecutive extension of an N-oligopeptidyl chain on a tetramate anchor. The synthetic product differed from the natural isolate in optical rotation, some NMR data, and cytotoxicities. Its antiproliferative effect on three human cancer cell lines was distinctly lower than that of related dolastatin 10 and belamide A. (C) 2018 Elsevier Ltd. All rights reserved.