572-67-8 EINECS 209-342-7 Isoreserpilin Methyl (19alpha,20alpha)-16,17-didehydro-10,11-dimethoxy-19-methyloxayohimban-16-carboxylate Oxayohimban-16-carboxylic acid, 16,17-didehydro-10,11-dimethoxy-19-methyl-, methyl ester, (19alpha,20alpha)-