Search results for "Dehydropeptide conformation"

showing 3 items of 3 documents

Enhanced β-turn conformational stability of tripeptides containing Δphe in cis over trans configuration

2013

Conformations of three pairs of dehydropeptides with the opposite configuration of the Delta Phe residue, Boc-Gly-Delta(Z/E)Phe-Phe-p-NA (Z- p -NA and E- p -NA), Boc-Gly-Delta(Z/E)Phe-Phe-OMe (Z-OMe and E-OMe), and Boc-Gly-Delta(Z/E)Phe-Phe-OH (Z-OH and E-OH) were compared on the basis of CD and NMR studies in MeOH, TFE, and DMSO. The CD results were used as the additional input data for the NMR-based calculations of the detailed solution conformations of the peptides. It was found that Z- p -NA, E- p -NA, Z-OMe, and Z-OH adopt the beta-turn conformations and E-OMe and E-OH are unordered. There are two overlapping type III beta-turns in Z- p -NA, type II' beta-turn in E- p -NA, and type II …

Dehydropeptide conformationCircular dichroismMagnetic Resonance SpectroscopyStereochemistryProtein ConformationPhenylalanineClinical BiochemistryTripeptideCircular dichroismTemperature coefficients of amide protonsBiochemistryNuclear magnetic resonancechemistry.chemical_compoundResidue (chemistry)Trans configurationchemistry [Oligopeptides]Amideotorhinolaryngologic diseasesHydrogen bondProtein StabilityDehydropeptidesCircular DichroismOrganic ChemistryStereoisomerismchemistryIntramolecular forceddc:540Dehydrophenylalanine configurationchemical synthesis [Oligopeptides]Conformational stabilitychemistry [Phenylalanine]OligopeptidesAmino Acids
researchProduct

Influence of solvents on conformation of dehydropeptides

2013

Abstract Structural investigations of dehydropeptides containing (Z)-dehydrophenylalanine in solvents characterized by different polarity are discussed. The conformational analysis are based on spectroscopic methods (NMR, CD), molecular modeling techniques and in case of the tripeptide, ab initio methods. The results of temperature experiment indicate, that the only conformation of the investigated hexapeptide 3 is stabilized by intramolecular hydrogen bonds. Depending on the length of the peptide chain, the polarity of solvent influences on arrangement of the side chain of the amino acids or of the main chain of the peptide.

Dehydropeptide conformationchemistry.chemical_classificationCircular dichroismMolecular modelDehydrophenylalanineHydrogen bondStereochemistryOrganic ChemistryAb initioPeptideTripeptideCircular dichroismSolvent polarityNMRAnalytical ChemistryInorganic ChemistrychemistryIntramolecular forceSide chainDehydropeptideSpectroscopyJournal of Molecular Structure
researchProduct

Effect of the ΔPhe residue configuration on a didehydropeptides conformation: A combined CD and NMR study.

2010

Conformations of two pairs of dehydropeptides with the opposite configuration of the ΔPhe residue, Boc-Gly-Δ(Z)Phe-Gly-Phe-OMe (Z-OMe), Boc-Gly-Δ(E)Phe-Gly-Phe-OMe (E-OMe), Boc-Gly-Δ(Z)Phe-Gly-Phe-p-NA (Z-p-NA), and Boc-Gly-Δ(E)Phe-Gly-Phe-p-NA (E-p-NA) were compared on the basis of CD and NMR studies in MeOH, trifluoroethanol (TFE), MeCN, chloroform, and dimethylsulfoxide (DMSO). The CD results were used as the additional input data for the NMR-based determination of the detailed solution conformations of the peptides. It was found that E-OMe is unordered and Z-OMe, Z-p-NA, and E-p-NA adopt the β-turn conformation. There are two overlapping β-turns in each of those peptides: type II and ty…

Models MolecularCircular dichroismanimal structuresdehydropeptide conformationMagnetic Resonance SpectroscopyStereochemistryProtein ConformationPhenylalanineBiophysicsStereoisomerismBiochemistrydehydrophenylalanine configurationBiomaterialschemistry.chemical_compoundResidue (chemistry)Protein structureotorhinolaryngologic diseasesMoleculeAmino Acid SequencePeptide sequenceChloroformintegumentary systemMolecular StructureCircular DichroismOrganic ChemistryTemperatureStereoisomerismGeneral MedicineNuclear magnetic resonance spectroscopySolutionsnuclear magnetic resonancedehydropeptideschemistrySpectrophotometryOligopeptidesBiopolymers
researchProduct