Abstract:
:For the study of hepatic bile acid transport in vivo, a series of modified bile salts were synthesized. The N-cholyl derivatives of L-leucine, L-alanine, D-alanine, beta-alanine, L-proline, and gamma-amino-butyric acid were prepared from cholic acid, ethyl chloroformate and the corresponding amino acid. Structural analysis of products was carried out mainly by electron impact mass spectrometry (20 eV) of the methyl ester/acetate derivatives. In all EI spectra, fragments in the lower mass region included McLafferty rearrangement ions (beta-cleavage) and product ions of gamma-cleavage in the vicinity of the amide linkage. In the upper mass region, fragmentation was characterized by consecutive eliminations of ketene and/or acetic acid from low intensity molecular ions. The purity of the products and their molecular weights were checked by a novel ionization technique in mass spectrometry, fast atom bombardment (FAB) mass spectrometry. FAB spectra were obtained from underivatized bile salts. The spectra were characterized by ions formed by attachment of a proton or an alkali ion to the bile salt to give intense M+H, M+Na, or M+K ions, which then showed little fragmentation.
journal_name
Steroidsjournal_title
Steroidsauthors
Ballatore AM,Beckner CF,Caprioli RM,Hoffman NE,Liehr JGdoi
10.1016/0039-128x(83)90007-7subject
Has Abstractpub_date
1983-02-01 00:00:00pages
197-206issue
2eissn
0039-128Xissn
1878-5867pii
0039-128X(83)90007-7journal_volume
41pub_type
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