102518-79-6 5,9-Methanocycloocta(b)pyridin-2(1H)-one, 5-amino-11-ethylidene-5,6,9,10-tetrahydro-7-methyl-, (5R,9R,11E)- 5,9-Methanocycloocta(b)pyridin-2(1H)-one, 5-amino-11-ethylidene-5,6,9,10-tetrahydro-7-methyl-, (5R-(5-alpha,9-beta,11E))- Huperzine Huperzine A