253790-50-0Relevant academic research and scientific papers
Permeation through phospholipid bilayers, skin-cell penetration, plasma stability, and CD spectra of α- And β-oligoproline derivatives
Kolesinska, Beata,Podwysocka, Dominika J.,Rueping, Magnus A.,Seebach, Dieter,Kamena, Faustin,Walde, Peter,Sauer, Markus,Windschiegl, Barbara,Meyer-ács, Mira,Vor Der Brüggen, Marc,Giehring, Sebastian
, p. 1 - 38 (2013/04/10)
After a survey of the special role, which the amino acid proline plays in the chemistry of life, the cell-penetrating properties of polycationic proline-containing peptides are discussed, and the widely unknown discovery by the Giralt group (J. Am. Chem. Soc. 2002, 124, 8876) is acknowledged, according to which fluorescein-labeled tetradecaproline is slowly taken up by rat kidney cells (NRK-49F). Here, we describe details of our previously mentioned (Chem. Biodiversity 2004, 1, 1111) observation that a hexa-β3-Pro derivative penetrates fibroblast cells, and we present the results of an extensive investigation of oligo-L- and oligo-D-α-prolines, as well as of oligo-β2h- and oligo-β3h-prolines without and with fluorescence labels (1-8; Fig. 1). Permeation through protein-free phospholipid bilayers is detected with the nanoFAST biochip technology (Figs. 2-4). This methodology is applied for the first time for quantitative determination of translocation rates of cell-penetrating peptides (CPPs) across lipid bilayers. Cell penetration is observed with mouse (3T3) and human foreskin fibroblasts (HFF; Figs. 5 and 6-8, resp.). The stabilities of oligoprolines in heparin-stabilized human plasma increase with decreasing chain lengths (Figs. 9-11). Time- and solvent-dependent CD spectra of most of the oligoprolines (Figs. 13 and 14) show changes that may be interpreted as arising from aggregation, and broadening of the NMR signals with time confirms this assumption. Copyright
Oligomers of β2- and of β3-homoproline: What are the secondary structures of β-peptides lacking H-bonds?
Abele, Stefan,Voegtli, Kurt,Seebach, Dieter
, p. 1539 - 1558 (2007/10/03)
To study the role of H-bonds in stabilizing β-peptidic secondary structures, we have synthesized β-oligopeptides (up to the octadecamer 12) consisting of β2- and β3-homoproline, i.e., β-peptides lacking amide protons. The enantiomer purity of the building block β2-homoproline (nipecotic acid, 4) was determined by HPLC analysis of the N-(2,4- dinitrophenyl) derivative 5 on a Chiralcel-OD column (cf. Fig. 2). The CD spectra of the all-(S)-β2- and all-(S)-β3-HPro-containing, β-peptides display novel and intensive CD patterns which may be indicative of a secondary structure (cf. Fig. 3). It is noteworthy that a distinct CD pattern was observed with the β3-HPro derivatives containing as few as three residues (7a). The crystal structure of a N-deprotected β3-HPro-tripeptide 7c is presented (cf. Figs. 4 and 5), and a model for the structure of β- peptides consisting of β3-HPro is discussed (cf. Figs. 6 and 7).
