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13C NMR of diterpenes: Use of the C-19 methyl group as a probe for locating a tetrasubstituted double bond

✍ Scribed by Martine Taran; Bernadette Arreguy-San Miguel; Bernard Delmond; Michel Petraud; Bernard Barbe

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

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✦ Synopsis

The 13C NMR spectra of diterpenic derivatives having pimarane, isopirnarane and the (13s) rosane skeleton have been recorded. This analysis has shown that the chemical shift of the 19-CH3 group depends on the position of the tetrasubstituted double bond in these skeletons. The C-19 methyl group can be used as a probe for distinguishing the isopirnarane from the rosane skeleton.

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