Studies on Bitter Peptides from Casein Hydrolyzate. XIV. Bitter Taste of Synthetic Analogs of Octapeptide, Arg–Gly–Pro–Phe–Pro–Ile–Ile–Val, Corresponding to the C-Terminal Portion ofβ-Casein
Studies on Bitter Peptides from Casein Hydrolyzate. XIV. Bitter Taste of Synthetic Analogs of Octapeptide, Arg–Gly–Pro–Phe–Pro–Ile–Ile–Val, Corresponding to the C-Terminal Portion ofβ-Casein
Peptide Synthesis in Aqueous Solution. V. Properties and Reactivities of (<i>p</i>-Hydroxyphenyl)benzylmethylsulfonium Salts for Direct Benzyl Esterification of<i>N</i>-Acylpeptides
Some (p-hydroxyphenyl)benzylmethylsulfonium salts were prepared. These compounds generated a benzyl cation and converted not only N-acylamino acids but also N-acylpeptides into their corresponding benzyl esters without causing the racemization.
In our contribution we showcase an application of photochemistry for Late Stage Functionalization (LSF) of amino acids and small peptides in an industrial medicinal chemistry environment. The radical intermediates generated under photochemical conditions from the C‐terminal carboxylates undergo rapid 1,4‐conjugate additions to a variety of Michael acceptors. The studied methodology is applicable to
Nonribosomalpeptidesynthetases (NRPSs) are multifunctional enzymes that produce a wide array of bioactive peptides. Here we show that a single tryptophan‐to‐serine mutation in phenylalanine‐specific NRPS adenylation domains enables the efficient activation of non‐natural aromatic aminoacids functionalized with azide and alkyne groups. The resulting 105‐fold switch in substrate specificity was achieved
N-Terminal L-prolyl or D-prolyl hexapeptide amides useful as Substance P agonists and/or antagonists and as analgesics and/or antihypertensives and a process for preparing them are disclosed.
Sulfonamides of homoproline and dipeptides as organocatalysts for Michael and aldol reactions
作者:Evaggelia Tsandi、Christoforos G. Kokotos、Sofia Kousidou、Valentine Ragoussis、George Kokotos
DOI:10.1016/j.tet.2008.12.008
日期:2009.2
Sulfonamides of the non-natural amino acid homoproline and the dipeptide Pro-Phe were synthesised and evaluated for their catalytic activity in Michael and aldol reactions. Sulfonamides of homoproline outperform proline and Pro-Phe in the Michael reaction, whereas sulfonamides of Pro-Phe lead to better results in the aldol reaction. The results of the present study show that the conversion of the carboxylic group of either homoproline or dipeptide Pro-Phe to the bioisosteric acyl sulfonamide group lead to improved organocatalysts. (C) 2008 Elsevier Ltd. All rights reserved.