Polymere Aminoschutzgruppen. Synthese von neuen poly[2-(N-vinylpyridinio)ethoxycarbonyl]-,2-(N-pyridinio)ethoxycarbonyl- und 2-(N-4-picolinio)ethoxycarbonyl-geschützten Aminoderivaten und kinetische Untersuchungen zur basisch induzierten Aminosäurefreisetzung
✍ Scribed by Ritter, Helmut ;Thöne, Jochen
- Publisher
- Wiley (John Wiley & Sons)
- Year
- 1987
- Weight
- 454 KB
- Volume
- 188
- Category
- Article
- ISSN
- 0025-116X
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✦ Synopsis
2-BromoethoxycarbonyI modified amino acids were reacted with pyridine, 4-picoline and poly(4-vinylpyridine) to yield the corresponding 2-(N-pyridinio)ethoxycarbonyl derivatives as water-soluble amino-protecting groups. The kinetics and activation energies of basicly induced cleavage of the amino acids were investigated by ' H NMR spectroscopy in a %O/NaOD medium. The polymeric salts were found to be more reactive than the low molecular weight pyridinium bromides because of electrostatic polymeric effects. Additionally, the kinetic measurements confirmed a ElcB mechanism for the cleavage of the urethane function. The formation of peptide bonds was performed in the case of poly[2-(N-4-vinylpyridinioethoxycarbonyl)]protected amino acids in aqueous medium by water-soluble carbodiimides. CH3 1