title: Heteronuclear NMR studies of the chromone alkaloids and revision of the structure of some piperidino-chromone alkaloids.
abstract: The 13C-NMR spectra of seven chromone alkaloids isolated from Schumanniophyton magnificum have been obtained. Assignment of signals was carried out with the help of heteronuclear coupling experiments and other correlation techniques on the alkaloids and their acyl derivatives. On the basis of the signals observed the structures of the piperidino-alkaloid schumannificine and its N-methyl and anhydro analogues have been revised to that of a piperidone ring linked to the noreugenin via a carbon-carbon bond and a lactol bridge.
authors.affiliation: Department of Pharmacy, King's College London, U.K.
authors.forename: P J
authors.initials: PJ
authors.lastname: Houghton
authors.forename: I M
authors.initials: IM
authors.lastname: Osibogun
authors.forename: T Z
authors.initials: TZ
authors.lastname: Woldemariam
authors.forename: K
authors.initials: K
authors.lastname: Jones
mesh_terms: D000470:Alkaloids / Q000737:chemistry*; D002867:Chromones / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry / Q000379:methods; D015394:Molecular Structure; D010880:Piperidines / Q000737:chemistry*; D010944:Plants / Q000737:chemistry
chemical_list: D000470:Alkaloids; D002867:Chromones; D010880:Piperidines