Conversion of dechlorodauricumine into miharumine by a cell-free preparation from cultured roots of Menispermum dauricum.

Dechlorodauricumine (5) and dechloroacutumine (6) were converted to miharumine (7) and dechloroacutumidine (8), respectively, by a cell-free preparation from cultured roots of Menispermum dauricum in the presence of FAD. The structures of 7 and 8 were elucidated on the basis of spectroscopic analyses and chemical conversion.

Conversion of dechlorodauricumine into chlorinated alkaloids in Menispermum dauricum root culture.

(15)N-Labeled dechlorodauricumine and dechloroacutumine were isolated from Menispermum dauricum roots cultured in a chloride-deficient medium, in which nitrogen-containing macro-components K(14)NO(3) and ((14)NH(4))(2)SO(4) were replaced by K(15)NO(3) and ((15)NH(4))(2)SO(4), respectively. These (15)N-labeled substrates were supplied independently to the roots cultured in a chloride-enriched medium. LC-ESI-MS analysis of alkaloids extracted from the roots, harvested 5 and 10 days after administering the (15)N-labeled substrates, revealed that the (15)N derived from dechlorodauricumine was much more effectively incorporated into chlorinated alkaloids than that derived from dechloroacutumine. These findings suggest that dechlorodauricumine is the principal precursor of the chlorinated alkaloids produced by M. dauricum roots.

Dechlorodauricumine from cultured roots of Menispermum dauricum.

Dechlorodauricumine, a possible organic substrate for biochlorination, was isolated from cultured roots of Menispermum dauricum, a rich source of chlorinated alkaloids. Its structure was established by spectroscopic and chemical methods.