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Triterpenoids. Part IV. Mass spectrometry of pentacyclic triterpenoids: 18β- and 18α-11-oxooleanolic acid derivatives

✍ Scribed by E. Wyrzykiewicz; U. Wrzeciono; L. Zaprutko

Publisher: John Wiley and Sons
Year: 1989
Tongue: English
Weight: 308 KB
Volume: 24
Category: Article
ISSN: 1076-5174
DOI: 10.1002/oms.1210240208

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✦ Synopsis

The mass spectral fragmentation of five pairs of 18g-and 18a-11-oxooleanolic acid derivatives la, 1b-5a, 5b are investigated and discussed. Fragmentation pathways, elucidation of which were assisted by accurate mass measurements and metastable transitions, are proposed. The obtained data create a safe basis for distinguishing the abovementioned 18 diastereomers.

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