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. 1987 May;84(1):144–147. doi: 10.1104/pp.84.1.144

Epoxidation in Vivo of Hyoscyamine to Scopolamine Does Not Involve a Dehydration Step

Takashi Hashimoto 1, Junko Kohno 1, Yasuyuki Yamada 1
PMCID: PMC1056542  PMID: 16665388

Abstract

Hyoscyamine is epoxidized to scopolamine via 6β-hydroxyhyoscyamine in several solanaceous plants. 6,7-Dehydrohyoscyamine has been proposed to be an intermediate in the conversion of 6β-hydroxyhyoscyamine to scopolamine on the basis of the observation that this unsaturated alkaloid is converted to scopolamine when fed to a Datura scion. To determine whether a dehydration step is involved in scopolamine biosynthesis, [6-18O]6β-hydroxyhyoscyamine was prepared from l-hyoscyamine and 18O2 using hyoscyamine 6β-hydroxylase obtained from root cultures of Hyoscyamus niger L. When [6-18O]6β-hydroxyhyoscyamine was fed to shoot cultures of Duboisia myoporoides R. BR., the labeled alkaloid was converted to scopolamine which retained 18O in the epoxide oxygen. It is concluded that 6β-hydroxyhyoscyamine is converted in vivo to scopolamine without a dehydration step.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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