ISSN:
1572-9001
Keywords:
Protected tripeptide
;
solution structure
;
crystal structure
;
X-ray analysis
;
NMR analysis
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract The solid-state structure of Boc-Gly-Trp-Ala-OBut was determined by single-crystal X-ray diffraction analysis. The tripeptide gave crystals belonging to the orthorhombic systemP212121 and at 122.0(5) K:a=11.0663(12),b=14.107(2),c=17.275(2) Å,V=2697.0(5) Å3Z=4,R(F)=0.0259, andR w(F)=0.0695. The peptide adopts a type-Iβ-turn in the solid state with a single, rather weak, intramolecular hydrogen bond between the Boc-CO and Ala-NH groups (N⋯O 3.082(1) Å, 〈NH⋯O 167(1)°). The conformation of the Boc-Gly-Trp-Ala-OBut peptide has also been studied by1H NMR spectroscopy. The solvent and temperature dependencies of NH chemical shifts suggests that this hydrogen bond is broken and that all amide protons are solvent exposed in CDCl3 and (CD3)2SO.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF02278735
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