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Triterpenoids. Part II—Carbon-13 NMR spectra of 18β- and 18α-11-oxooleanolic acid derivatives

✍ Scribed by U. Wrzeciono; L. Zaprutko; J. Budzianowski; H. Wojtowicz; D. Dubowska

Publisher
John Wiley and Sons
Year
1987
Tongue
English
Weight
313 KB
Volume
25
Category
Article
ISSN
0749-1581

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✦ Synopsis

The 13C NMR spectra of five pairs of 18p-and 18r~-ll-oxooleanolic acid derivatives have been assigned. The chemical shifts of C-12, C-13, C-17, C-18 and C-28 are of diagnostic value for the determination of the DIE junction stereochemistry. KEY WORDS "C NMR 18p-11 -oxooleanolic acid derivatives 18a-1 1 -oxooleanolic acid derivatives D/E ring junction ~ ~ ~ ~~ ~ Compounds C-12 C-13 C-16

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