✍ Scribed by Anthony A. Ribeiro; Robert Saltman; Murray Goodman
No coin nor oath required. For personal study only.
The syntheses of three series of glutamate oligopeptides attached to a macromolecular solubilizing polyoxyethylene (POE) group Boc-[Glu(OMe)],-OPOE, Ac-[Glu(OMe)],-OPOE, pGlu-[Gl~(0Me)]~~,-0POE ( n = 1-7) and their various analogs specifically deuterated a t individual a-CH positions using the liquid-phase method of peptide synthesis are described. It was shown that stepwise synthesis using the symmetrical anhydride gave homo-oligopeptides that are analytically pure. Fragment condensation methods using DCC-HOBt yield POE-peptides with POE-HOBt impurities but the peptide synthesis may be carried stoichiometrically with smaller quantities of amino acid derivatives. 360 MHz H-nmr conformational studies of these homo-oligopeptides in DMSO-4 are presented. The adeuterated peptides are shown to allow unequivocal homoligopeptide backbone NH assignments.
📜 SIMILAR VOLUMES
Three analogues of the tridecapeptide amide H-Leu-( Glu) ,-Ala-Tyr-Gly-Nle-Asp-Phe-NH2 were synthetized with a-deuterated glutamate residues in specific positions in order to assign unambiguously the 'H nmr spectrum of the parent peptide in water and in watertrifluoroethanol mixtures. The synthetic