| Autor: |
Potrzebowski, M.J., Tekely, P., Blaszczyk, J., Wieczorek, M.W. |
| Předmět: |
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| Zdroj: |
Journal of Peptide Research; Oct2000, Vol. 56 Issue 4, p185, 10p |
| Abstrakt: |
A crystalline sample of N-benzoyl-DL-phenylalanine 1 and a polycrystalline sample of N-benzoyl-L-phenylalanine 2 were studied using ¹3;C high-resolution solid-state NMR spectroscopy. The X-ray structure of the DE form was established. Sample 1 crystallizes in a monoclinic form with a P2[sub 1]/c space group, a=11.338(1) Å, b=9.185(1) Å, c=14.096(2) Å, β=107.53(3)°, V=1400(3)ų, Z=4 and R=0.053. The principal elements of the [sup 13]C chemical shift tensors δii for 1 and 2, selectively [sup 13]C (99%) labeled at the carboxyl groups were calculated. On the basis of [sup 13]C δii analysis the hydrogen bonding pattern for sample 2 was deduced. Enriched samples were used to establish the intermolecular distance between chemically equivalent nuclei for 1 and spatial proximity in heterogeneous domain for 2, employing the ODESSA pulse sequence. The consistence of the complementary approach covering X-ray data, analysis of the [sup 13]C δii parameters and ODESSA results is revealed. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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