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13C-NMR. Spectroscopy of Naturally Occuring Substances. XLII. Conformational analysis of quebrachamine-like indole alkaloids and related substances

✍ Scribed by Ernest Wenkert; Edward W. Hagaman; Nicole Kunesch; Nai-yi Wang; Béla Zsadon

Publisher
John Wiley and Sons
Year
1976
Tongue
German
Weight
858 KB
Volume
59
Category
Article
ISSN
0018-019X

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✦ Synopsis

Abstract

The ^13^C shifts of 16α‐ and 16β‐substituted derivatives of quebrachamine, 14,15‐dehydroquebrachamine, cleavamine, 15,20α‐dihydrocleavamine and 15,20β‐dihydrocleavamine are determined and correlated with possible conformations of these tetracycles. The method of analysis of the C(16) configuration of these compounds, which emanated from this study, is used for the determination of the configuration of the site of coupling of vindoline and cleavamine β‐chloroindolenine.

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