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Carbon-13 n.m.r. study of naturally occurring xanthones

✍ Scribed by Philip W. Westerman; Sarath P. Gunasekera; M. Uvais; S. Sultanbawa; Rymantas Kazlauskas

Publisher: John Wiley and Sons
Year: 1977
Tongue: English
Weight: 487 KB
Volume: 9
Category: Article
ISSN: 0749-1581
DOI: 10.1002/mrc.1270091106

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✦ Synopsis

Abstract

The ^13^C n.m.r. spectra of 36 naturally occurring xanthones are reported and all chemical shifts assigned. The shifts in substituted xanthones can be predicted from substituent effects evaluated for simple derivatives. The agreement between calculated and observed shifts decreases as the extent of substitution in the xanthone increases.

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