Calyciphyllines A and B, two novel hexacyclic alkaloids from Daphniphyllum calycinum
Hiroshi Morita1, Jun'ichi Kobayashi
1Graduate School of Pharmaceutical Sciences, Hokkaido University, Sapporo 060-0812, Japan.
Organic Letters
|August 2, 2003
Abstract:
[structure: see text] Two types of Daphniphyllum alkaloids with unprecedented fused-hexacyclic ring systems, calyciphyllines A (1) and B (2), have been isolated from the leaves of Daphniphyllum calycinum (Daphniphyllaceae), and the structures and relative stereochemistry were elucidated on the basis of spectroscopic data.
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