99597-71-4Relevant academic research and scientific papers
Solid-phase synthesis of lipidated Ras peptides employing the Ellman sulfonamide linker
Triola, Gemma,Gerauer, Marc,Gcrmer, Kristina,Brunsveld, Lucas,Waldmann, Herbert
supporting information; experimental part, p. 9585 - 9591 (2010/12/18)
A detailed study on the solid-phase synthesis of lipidated peptides of the Ras family employing the Ellman sulfonamide linker is reported. Using the C-terminal N-Ras sequence, critical issues such as lipidated amino acid resin loading, peptide elongation in the presence of labile groups and optimized conditions for release of the peptides were investigated. A versatile methodology for the synthesis of peptides with diverse lipid motifs and C-terminal methyl esters has accordingly been established.
A novel and efficient method for cleavage of phenacylesters by magnesium reduction with acetic acid
Kokinaki, Stella,Leondiadis, Leondios,Ferderigos, Nikolas
, p. 1723 - 1724 (2007/10/03)
(Equation Presented) In the present study, we use magnesium turnings as a new deprotection reagent for the phenacyl group during orthogonal organic synthesis in the presence of other esters and sensitive protecting groups. By applying the new magnesium turnings/acetic acid deprotection method, phenacyl group can be more easily combined with other protecting groups that are not compatible with the zinc/acetic acid method.
C- and N-terminal residue effect on peptide derivatives' antagonism toward the formyl-peptide receptor
Dalpiaz, Alessandro,Ferretti, Maria E.,Vertuani, Gianni,Traniello, Serena,Scatturin, Angelo,Spisani, Susanna
, p. 187 - 196 (2007/10/03)
The biological action of several X-Phe-D-Leu-Phe-D-Leu-Z (X = 3′,5′-dimethylphenyl-ureido; Z = Phe, Lys, Glu, Tyr) analogues was analysed on human neutrophils to evaluate their ability to antagonize formyl-peptide receptors. X-Phe-D-Leu-Phe-D-Leu-Phe analogues obtained as C-terminal olo or amido derivatives and T-Phe-D-Leu-Phe-D-Leu-Phe analogues (T = thiazolyl-ureido) were also analysed. The activities of pentapeptide derivatives were compared with those of X-Phe-D-Leu-Phe-D-Leu-Phe chosen as reference antagonist. Our results demonstrate that X-Phe-D-Leu-Phe-D-Leu-Phe-olo, X-Phe-D-Leu-Phe-D-Leu-Glu and X-Phe-D-Leu-Phe-D-Leu-Tyr are more active antagonists than X-Phe-D-Leu-Phe-D-Leu-Phe. The presence of Lys (X-Phe-D-Leu-Phe-D-Leu-Lys) seems, instead, to inhibit the formyl-peptide receptor antagonist properties. The presence of the N-terminal thiazolyl-ureido group seems to considerably contribute to the receptor antagonist properties of T-Phe-D-Leu-Phe-D-Leu-Phe-OH. The introduction of the C-terminal methyl ester (T-Phe-D-Leu-Phe-D-Leu-Phe-OMe) or amido group (X-Phe-D-Leu-Phe-D-Leu-Phe-NH2) appears detrimental for the affinity and formyl-peptide receptor antagonist properties of the Phe-D-Leu-Phe-D-Leu-Phe derivatives. The examined peptides inhibit superoxide anion production and lysozyme release more efficaciously than neutrophil chemotaxis.
Efficient and Highly Selective Copper(II) Transport across a Bulk Liquid Chloroform Membrane Mediated by Lipophilic Dipeptides
Cleij, Marco C.,Scrimin, Paolo,Tecilla, Paolo,Tonellato, Umberto
, p. 5592 - 5599 (2007/10/03)
Several structurally simple N-monoalkylated and -dialkylated dipeptides made of α-amino acids Gly, Phe, and Leu, 1-11, were synthesized and investigated as carriers for the transport of Cu(II), Zn(II), and Ni(II) from an aqueous pH = 5.6 buffer source to a 0.1 M HCl receiving phase across a bulk chloroform membrane. The proton-driven translocation was followed during the process by analyzing the metal ion concentrations in the three phases. The transport efficiency depends on the ease of formation of a neutral complex with Cu(II) (the peptide group and carboxylic acid being deprotonated) at the source-chloroform interface and on that of its disruption by protonation at the receiving phase: the carrier's lipophilicity favors the metal ion uptake and not the release. By modulating the length of the N-alkyl chains and the hydrophobicity of the dipeptide moiety, a quite remarkable transport efficiency was observed for Cu(II), in most cases superior to that of the industrial extractant Kelex 100. Moreover, using L,L- and L,D-N-octyl-PheLeu as carriers, remarkable diastereomeric effects were observed in the rate of uptake and release of Cu(II) ion although the differences mutually compensate in the overall transport rate. Under the conditions used the carriers are much less effective in the translocation of Zn(II) and Ni(II) and their transport efficiency drops dramatically in the presence of Cu(II), the latter being favored by factors of 1.2 × 103 and > 104, respectively. Such very high selectivities depend on the fact that only Cu(II) among other transition metal ions can form neutral complexes at the pH value of the source phase.
