| Autor: |
Compernolle, F., Vanderhaeghe, H., Janssen, G. |
| Zdroj: |
Organic Mass Spectrometry; 1972, Vol. 6 Issue 2, p151-166, 16p |
| Abstrakt: |
The electron-impact induced fragmentation of staphylomycin S (I) and related cyclodepsipeptides (II to V) is mainly initiated by elimination of an azomethin molecule (RCHNR′), i.e. 1,2-dehydro-4-oxopiperidine for I and II, 1,2-dehydro-4-hydroxy-piperidine for III and IV, and an unknown hydroxy-1,2-dehydro-4-oxopiperidine for VI. Cyclic imino acids, e.g. a pipecolic acid derivative for I to IV and 4-hydroxyproline for etamycin (IX) preferentially trigger this reaction. Clearcut evidence for the amino acid sequence is given by the mass spectra of the linear peptides obtained from I, V and IX by alkaline hydrolysis of the lactone function and esterification of the carboxy group. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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