(5bR)-5,5bα,6,6aβ,10,11,16,16b,16cα,17,19,20-Dodecahydro-16bβ-methylbisindolo[2',3':3,4]pyrido[2,1-a:2',1'-g][2,7]naphthyridine-7-carboxylic acid methyl ester

Description

This alkaloid also occurs in the leaves of Uncaria gambier and forms colourless crystals from MeOH. It is, unlike the remaining alkaloids, dextrorotatory with [α]²⁰_D + 160° (MeOH) but the ultraviolet spectrum in EtOH is almost identical with those of the preceding bases, having absorption maxima at 226 and 292 ITIJ1 with a shoulder at 287 mfl. On catalytic hydrogenation it gives the dihydro derivative, m.p. 225-230°C.

References

Merlini et al., Tetrahedron, 26,2259 (1970)