New diterpenoid alkaloids were isolated from Delphinium elatum cv. Pacific Giant.
Melpheline is an unusual diterpenoid alkaloid with a 7,8-dioxymethylene group.
19-Oxoisodelpheline is the first reported lycoctonine-type C19-diterpenoid alkaloid with a 7,8-dioxymethylene moiety and a 19-oxo group.