85995-50-2Relevant academic research and scientific papers
Simplified beta-glycosylation of peptides
Zhang, Yonglian,Knapp, Spencer
, p. 2891 - 2903 (2018/05/08)
A simple and effective activating system for S-phenyl thioglycosides, namely N-iodosuccinimide and catalytic copper(I) triflate, promotes beta-O-glycosylation at the serine and threonine hydroxyls of “mono-,” di-, and tripeptides. The same activator combination promotes carboxamide beta-N-glycosylation of asparagine-containing mono-, di, and tri-peptides, as well as a nucleoside carboxamide and a sulfonamide. An important feature of the copper(I) triflate method is that undesired amide O-glycosylation is largely circumvented. For both sets of biologically important acceptor sites (HO– and –CONH2), a beta-GlcNAc-equivalent donor is demonstrated to provide the linkages efficiently. Streamlined deprotection sequences have been developed based on global hydrogenolysis that lead smoothly to the parent glycopeptides. The core glycopeptide region for biological protein N-glycosylation, represented by N4-(β-N-acetyl-D-2-glucosaminyl)-Asp-Gly-Thr-OH, has been prepared in solution, purified, and characterized as the fully deprotected (mono)glycosylated tripeptide.
Site-selective solid phase synthesis of carbonylated peptides
Waliczek, Mateusz,Kijewska, Monika,Stefanowicz, Piotr,Szewczuk, Zbigniew
, p. 1353 - 1365 (2015/06/16)
Abstract The aim of our research was to design an efficient method for the solid phase synthesis of carbonylated peptides. For this purpose, we designed and synthesized a fully protected derivative Fmoc-amino(2,5,5-trimetyhyl-1,3-dioxolan-2-yl)acetic acid
Synthesis and evaluation of lysophosphatidylserine analogues as inducers of mast cell degranulation. Potent activities of lysophosphatidylthreonine and its 2-deoxy derivative
Iwashita, Masazumi,Makide, Kumiko,Nonomura, Taro,Misumi, Yoshimasa,Otani, Yuko,Ishida, Mayuko,Taguchi, Ryo,Tsujimoto, Masafumi,Aoki, Junken,Arai, Hiroyuki,Ohwada, Tomohiko
experimental part, p. 5837 - 5863 (2010/03/24)
In response to various exogenous stimuli, mast cells (MCs) release a wide variety of inflammatory mediators stored in their cytoplasmic granules and this release initiates subsequent allergic reactions. Lysophosphatidylserine (lysoPS) has been known as an exogenous inducer to potentiate histamine release from MCs, though even at submicromolar concentrations. In this study, through SAR studies on lysoPS against MC degranulation, we identified lysoPT, a threonine-containing lysophospholipid and its 2-deoxy derivative as novel strong agonists. LysoPT and its 2-deoxy derivative induced histamine release from MCs both in vitro and in vivo at a concentration less than one-tenth that of lysoPS. Notably, lysoPT did not activate a recently proposed lysoPS receptor on MCs, GPR34, demonstrating the presence of another undefined receptor reactive to both lysoPS and lysoPT that is involved in MC degranulation. Thus, the present strong agonists, lysoPT and its 2-deoxy derivative, will be useful tools to understand the mechanisms of lysoPS-induced activation of degranulation of MCs. 2009 American Chemical Society.
Aqueous phosphoric acid as a mild reagent for deprotection of tert-butyl carbamates, esters, and ethers
Li, Bryan,Berliner, Martin,Buzon, Richard,Chiu, Charles K.-F.,Colgan, Stephen T.,Kaneko, Takushi,Keene, Nandell,Kissel, William,Le, Tung,Leeman, Kyle R.,Marquez, Brian,Morris, Ronald,Newell, Lisa,Wunderwald, Silke,Witt, Michael,Weaver, John,Zhang, Zhijun,Zhang, Zhongli
, p. 9045 - 9050 (2007/10/03)
(Chemical Equation Presented) Aqueous phosphoric acid (85 wt %) is an effective, environmentally benign reagent for the deprotection of tert-butyl carbamates, tert-butyl esters, and tert-butyl ethers. The reaction conditions are mild and offer good selectivity in the presence of other acid-sensitive groups, including CBZ carbamates, azetidine, benzyl and methyl esters, TBDMS, and methyl phenyl ethers. The mildness of the reaction is further demonstrated in the synthesis of clarithromycin derivative 4, in which a tert-butyl ester is removed in the presence of cyclic carbamate, lactone, ketal, acetate ester, and epimerizable methyl ketone functionalities. The reaction preserves the stereochemical integrity of the substrates. The reactions are high yielding, and the workup is convenient.
Synthesis of δ-(L-α-aminoadipoyl)-L-cysteinyl-D-(O-methyl)-D- allothreonine a substrate for isopenicillin-N synthase and its O-Methyl-D- threonine epimer
Petursson, Sigthor,Baldwin, Jack E.
, p. 6001 - 6010 (2007/10/03)
The paper describes the synthesis of two epimeric tripeptides δ-(L-α- aminoadipoyl)-L-cysteinyl-D-(O-methyl)-D-threonine (13) and δ-(L-α- aminoadipoyl)-L-cysteinyl-D-(O-methyl)-D-allothreonine (14), modified substrates for the isopenicillin-N synthase enz
13C NMR Spectroscopy, a Useful Tool To Determine the Enantiomeric Purity of Synthetic Threonine-Containing Glycopeptides. Spectra of Diastereoisomeric α- and β-D-Galactopyranosyl-L- and -D-threonine and -L- and -D-allothreonine
Pavia, A. A.,Lacombe, J. M.
, p. 2564 - 2568 (2007/10/02)
Further studies of O-glycosyl amino acids by natural-abundance 13C NMR spectroscopy are presented.Carbon-13 NMR spectra of diastereoisomeric α- and β-D-galactopyranosyl-L-threonine, -D-threonine, -L-allothreonine, and -D-allothreonine showed distinct anom
