Synonyms: Bisindolo[2',3':3,4]pyrido[2,1-a:2',1'-g][2,7]naphthyridine-7-carboxylicacid, 5,5b,6,6a,10,11,16,16b,16c,17,19,20-dodecahydro-16b-methyl-, methylester, (5bR,6aS,16bR,16cS)- (9CI); Roxburghine B (8CI); Roxburghine, (19b,20a)-; 19,20-Diepiroxburghine; 20-Epiroxburghine E;Bisindolo[2',3':3,4]pyrido[2,1-a:2',1'-g][2,7]naphthyridine-7-carboxylic acid,5,5b,6,6a,10,11,16,16b,16c,17,19,20-dodecahydro-16b-methyl-, methyl ester,[5bR-(5ba,6ab,16ba,16cb)]-