Synonyms: (3β,16E)-16,17,18,19-Tetradehydro-17-methoxycorynan-16-carboxylic acid methyl ester;18,19-Didehydrohirsutine;Δ18-Hirsutine;(3-beta,16E)-16,17,18,19-Tetradehydro-17-methoxy-corynan-16-carboxylic acid methyl ester;Corynan-16-carboxylic acid, 16,17,18,19-tetradehydro-17-methoxy-, methyl ester, (3-beta,16E)-;Corynan-16-carboxylic acid, 16,17,18,19-tetrahydro-17-methoxy-, methyl ester, (3beta,16E)-;delta(Sup 18)-hirsutine