Mbandakamines A and B, unsymmetrically coupled dimeric naphthylisoquinoline alkaloids, from a Congolese Ancistrocladus species

Abstract

Mbandakamines A (1) and B (2), isolated from the leaves of an as yet unidentified Congolese Ancistrocladus species, are the first dimeric naphthylisoquinoline alkaloids with an unsymmetrically coupled central biaryl axis. Their novel 6',1″-coupling type implies a hitherto unprecedented peri-peri coupling in one of the naphthalene parts, leading to the as yet highest steric hindrance at the central axis and a total of seven elements of chirality. Mbandakamine A exhibits good antimalarial activity.