29776-70-3Relevant articles and documents
Factors Affecting the Stabilization of Polyproline II Helices in a Hydrophobic Environment
Zanna, Nicola,Milli, Lorenzo,Del Secco, Benedetta,Tomasini, Claudia
supporting information, p. 1662 - 1665 (2016/04/26)
Several parameters have a critical importance for the stabilization of either polyproline I (PPI) or polyproline II (PPII) helices in a hydrophobic environment. Among them, it was found out that the concentration is crucial as polyprolines at 3 mM concent
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
Cis-trans proline isomerization effects on collagen triple-helix stability are limited
Dai, Nan,Etzkorn, Felicia A.
supporting information; experimental part, p. 13728 - 13732 (2010/01/06)
We investigated the effect of restricting cis-trans proline isomerization on collagen triplehelix stability. The Pro residues at the Xaa and Yaa positions of an (Xaa-Yaa-Gly) triplet were replaced by a Pro-trans-Pro alkene isostere in the host-guest pepti
PS-IIDQ: a supported coupling reagent for efficient and general amide bond formation
Valeur, Eric,Bradley, Mark
, p. 8855 - 8871 (2008/02/11)
Polystyrene-IIDQ, a polymer-supported coupling reagent, was synthesized in three steps from Merrifield resin in 86% overall conversion. This reagent efficiently coupled carboxylic acids to amines in good yields and high purities, required no pre-activation step, and was tolerant of the order of reagent addition. PS-IIDQ was observed to be more efficient than polymer-supported carbodiimides (PS-EDC and PS-DCC) and gave higher yields than HATU for general amide bond formation, including the coupling of anilines and hindered substrates. When evaluated with five carboxylic acids and nine amines (including anilines and secondary amines) PS-IIDQ gave an average isolated yield of 73%.
Microwave accelerated high speed solution synthesis of peptides employing HATU/HOAt
Sudarshan, Naremaddepalli S.,Suresh Babu, Vommina V.
, p. 1509 - 1511 (2007/10/03)
The chemical synthesis of peptides employing HATU/HOAt as a coupling agent under microwave irradiation has been described. The couplings found to be complete in 30-40 s. The yield as well as purity of the peptides made is found to be good. All the peptide
1-Ethyl 2-halopyridinium salts, highly efficient coupling reagents for hindered peptide synthesis both in solution and the solid-phase
Li, Peng,Xu, Jie-Cheng
, p. 8119 - 8131 (2007/10/03)
1-Ethyl-2-halopyridinium salts, BEP, FEP, BEPH and FEPH, were synthesized and proved to be very effective for the synthesis of hindered peptides containing N-methylated or C(α),C(α)-dialkylated amino acid residues. HPLC monitoring of model reactions indicated that these pyridinium salts demonstrated higher reactivities, lower racemization than the commonly used halogenated uronium and phosphonium salts. The efficiency of these pyridinium type coupling reagents was further proved by the synthesis of a series of hindered oligopeptides and active esters with good yields and convenient workup. The 8-11 tetrapeptide fragment of Cyclosporin A (CsA) and the pentapeptide moiety of Dolastatin 15 were also successfully synthesized using these pyridinium salts. The efficiency of these pyridinium type coupling reagents for SPPS was also demonstrated by the solid-phase synthesis of the extremely hindered 8-11 peptide segment of CsA and the linear undecapeptide of CsO. The mechanism of the pyridinium salt mediated coupling reactions was also studied by 1H NMR, IR and HPLC. It was proposed that the major reactive intermediates were the corresponding acyl halide and acyloxypyridinium salts of the N-protected amino acid or peptide. (C) 2000 Elsevier Science Ltd.
2-Bromo-1-ethyl pyridinium tetrafluoroborate (BEP): A powerful coupling reagent for N-methylated peptide synthesis
Li, Peng,Xu, Jie Cheng
, p. 204 - 205 (2007/10/03)
2-Bromo-1-ethyl pyridinium tetrafluoroborate (BEP) was firstly utilized to the synthesis of peptides containing N-methyl amino acid residues both in solution and solid phase, and demonstrated high reactivity, low racemization and excellent yields, which w
Peptide Synthesis in Aqueous Solution. V. Properties and Reactivities of (p-Hydroxyphenyl)benzylmethylsulfonium Salts for Direct Benzyl Esterification of N-Acylpeptides
Nakata, Takashi,Nakatani, Masaru,Takahashi, Masatoshi,Okai, Jiro,Kawaoka, Yoshiaki,Kouge, Katsushige,Okai, Hideo
, p. 1099 - 1106 (2007/10/03)
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.
Proline derivatives possessing prolyl endopeptidase-inhibitory activity
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, (2008/06/13)
Novel proline derivatives of the following formula (I) STR1 wherein each symbol is as defined in the specification, which specifically inhibit prolyl endopeptidase activity and can be used for the prevention and/or treatment of dementia and amnesia as agents which act directly on the central symptoms of dementia.
Dipeptide derivatives and antihypertensive drugs containing them
-
, (2008/06/13)
There are disclosed dipeptide derivatives represented by the general formula: STR1 wherein R1 is a radical selected from the group consisting of alkyl, aralkyl and aryl groups optionally containing one or more substituent groups, R2 is a radical selected from the group consisting of hydrogen atoms and alkyl, aralkyl and aryl groups optionally containing one or more substituent groups, R3 is a radical selected from the group consisting of hydrogen atoms and alkyl, aralkyl and aryl groups optionally containing one or more substituent groups, R4 is a radical selected from the group consisting of hydrogen atoms and alkyl, aralkyl and aryl groups optionally containing one or more substituent groups, and R5 is a radical selected from the group consisting of hydroxyl, amino, hydroxyamino, alkyloxy, aralkyloxy, aryloxy, alkylamino, aralkylamino, arylamino, alkyloxyamino, aralkyloxyamino, aryloxyamino, acylamino and sulfonylamino groups, which alkyloxy, aralkyloxy and aryloxy groups optionally containing one or more substituent groups; wherein R3 may be combined with R2 or R4 to form an alkylene bridge optionally containing one or more oxygen atoms, sulfur atoms and nitrogen atoms and optionally containing one or more substituent groups. However, certain dipeptide derivatives within the above general formula are excluded from the invention. The dipeptide derivatives are useful for the treatment of hypertension.