Ajmaline pathway vomilenine

FALKENHAGEN, H., STOCKIGT, J., Enzymatic biosynthesis of vomilenine, a key intermediate of the ajmaline pathway, catalyzed by a novel cytochrome P450-dependent enzyme from plant cell cultures of Rauwoljia serpentina. Z. Naturforsch., 1995, 50C, 45-53. 

Biosynthesis R. is derived from vomilenine, an intermediate in the biosynthetic pathway to the antiarrhyth-mic ajmaline, by glucosylation. The corresponding glucosyl transferase is membrane-bound, dependent on uridine diphosphate glucose, and has a high substrate specificity. A soluble, substrate-specific glu-cosidase effects the reversal of this reaction see also Rauvolfia alkaloids. 

Plant Cells. The metabolism of unlabelled alkaloids in plant cell cultures has been followed using heteronuclear multiple quantum coherence NMR. The addition of ajmaline to cell suspension cultures of somatic hybrids of Rauvolfia serpentina Benth. ex Kurz and Rhazya stricta Decaisne (R x R cells) resulted in its conversion to raumacline. When, vinorine, an intermediate of ajmaline metabolism, was added to suspensions on R x R cells, vellosimine was formed and then converted to 10-deoxysarpagine. However, vinorine was apparently metabolised by a second pathway to vomilenine or raucaffricine." ... 

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