title: Ammonia chemical ionization tandem mass spectrometry in structural determination of alkaloids. II. Tetraponerines from pseudomyrmecine ants.
abstract: Chemical ionization tandem mass spectrometry (CI-MS/MS) of alkaloids with ammonia reagent gas and collision-activated dissociation as well as EI-MS/MS were applied to the tetraponerine alkaloids in extracts from six pseudomyrmecine ants of the genus Tetraponera. The MS/MS techniques along with gas chromatography Fourier transform infrared (GC/FTIR) spectra allowed identification in two extracts of seven of the eight known tetraponerines. The EI-MS/MS fragmentations proved diagnostic for the ring system and the CI-MS/MS patterns for the C-8 or C-9 substitution, while the Bohlmann bands in FTIR spectra were diagnostic for the C-8 or C-9 configurations. An Indian ant (T. allaborans) had T-2, T-4 and T-8, while a Chinese ant (T. binghami) had T-5, T-6, T-7 and T-8. Four other ants, T. rufonigra (India), T. penzigi (Africa), T. clypeata (Africa) and T. sp. cf. emeryi (Africa), had no tetraponerines.
authors.affiliation: Laboratory of Bioorganic Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0820, USA.
authors.forename: H M
authors.initials: HM
authors.lastname: Garraffo
authors.forename: T F
authors.initials: TF
authors.lastname: Spande
authors.forename: P
authors.initials: P
authors.lastname: Jain
authors.forename: T
authors.initials: T
authors.lastname: Kaneko
authors.forename: T H
authors.initials: TH
authors.lastname: Jones
authors.forename: M S
authors.initials: MS
authors.lastname: Blum
authors.forename: T M
authors.initials: TM
authors.lastname: Ali
authors.forename: R R
authors.initials: RR
authors.lastname: Snelling
authors.forename: L A
authors.initials: LA
authors.lastname: Isbell
authors.forename: H G
authors.initials: HG
authors.lastname: Robertson
authors.forename: J W
authors.initials: JW
authors.lastname: Daly
mesh_terms: D000470:Alkaloids / Q000737:chemistry* / Q000302:isolation & purification; D000818:Animals; D001000:Ants; D002849:Chromatography, Gas / Q000379:methods; D013058:Mass Spectrometry / Q000379:methods; D015394:Molecular Structure; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods; D017550:Spectroscopy, Fourier Transform Infrared / Q000379:methods
chemical_list: D000470:Alkaloids