Crystal Structure of (-)-Corycavinium(+)-10-Camphorsulfonate, a Biosynthetic Intermediate to Hexahydrobenzo[c]phenanthridine Alkaloids

Abstract

The crystal structure of (—)-corycavinium (+)-10-camphorsulfonate has been investigated by X-ray analysis.
The structure of (-)-corycavinium ion ( = (-)-(7S,13S,14R)-5,6,13,13a-tetrahydro-l3a-hydroxy-7-methyl-
2,3;9,10-bis(methylenedioxy)-8H-dibenzo[a,g]quinolizinium), has been determined. The conformation with B/Ccis
-conjunction, a twisted half-chair of ring B, and a half-chair of ring C, as well as a -oriented substituted groups
N - M e , C - Me, and C - O H is revealed. Feeding experiments with cell suspension cultures of Corydalis incisa
(Papaveraceae) defined the intermediacy of (—)-corycavinium in the route from protoberberine-type to hexahydrobenzo[
c]phenanthridine-type of alkaloids. On the basis of the present crystal conformation, the
stereospecificity of the relating enzyme is biogenetically considered.