title: The characterization and structure-activity evaluation of toxic norditerpenoid alkaloids from two Delphinium species.
abstract: A new N-(methylsuccinimido)anthranoyllycoctonine norditerpenoid alkaloid, geyerline, has been isolated and characterized from extracts of the poisonous larkspur Delphinium glaucum. A previously described norditerpenoid alkaloid, grandiflorine, has also been isolated from Delphinium geyeri. Both alkaloids are closely related structurally to the potent neurotoxin methyllycaconitine, established as the primary toxin in many larkspurs poisonous to cattle. Mouse bioassay tests showed grandiflorine to possess toxicity comparable to methyllycaconitine, while its synthetically derived monoacetate, grandiflorine acetate, and geyerline are significantly less toxic.
authors.affiliation: Western Regional Research Center, Agricultural Research Service, United States Department of Agriculture, 800 Buchanan Street, Albany, California, USA. gmann@pw.usda.gov
authors.forename: G D
authors.initials: GD
authors.lastname: Manners
authors.forename: K E
authors.initials: KE
authors.lastname: Panter
authors.forename: J A
authors.initials: JA
authors.lastname: Pfister
authors.forename: M H
authors.initials: MH
authors.lastname: Ralphs
authors.forename: L F
authors.initials: LF
authors.lastname: James
mesh_terms: D000470:Alkaloids / Q000737:chemistry / Q000633:toxicity*; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004224:Diterpenes / Q000737:chemistry / Q000633:toxicity*; D007928:Lethal Dose 50; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D051379:Mice; D010947:Plants, Toxic / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet; D013329:Structure-Activity Relationship
chemical_list: D000470:Alkaloids; D004224:Diterpenes