Electrospray tandem mass spectrometry for structural characterization of aporphine- benzylisoquinoline alkaloids.
Electrospray mass spectrometry and tandem mass spectrometry techniques were utilized to elucidate the structures of ten aporphine-benzylisoquinoline alkaloids, consisting of monoether link between aporphine and benzyltetrahydroisoquinoline units, which were isolated and identified previously from a variety of Thalictrum sp. (Ranunculaceae family) based mainly on the UV, IR, CD, NMR, EI-MS, CI-MS, derivatization, and chemical degradation techniques. In this investigation, protonated molecules, [M+H]+ ions, for nine tertiary alkaloids, a molecular ion, [M+'] ion, for a quaternary alkaloid, and very intense doubly- protonated molecules, [M+2H]2+ ions (100% of relative abundance) in Q1 Scan MS spectra, and prominent as well as diagnostic product ions for structural information in the tandem MS/MS spectra were observed for all investigated alkaloids each in nanogram quantities. More than 10 microg quantities of each investigated alkaloid or other isoquinoline and aporphine analogs needed for the CI-MS, EI-MS and FAB-MS analysis from the previous studies.
Wu
Wu-Nan
WN
Division of Preclinical Drug Evaluation, Johnson & Johnson Pharmaceutical Research & Development, LLC, Spring House, PA 19477, USA. jawee@erols.com
Moyer
Michael D
MD
D001060:Aporphines / Q000032:analysis / Q000737:chemistry*; D044182:Benzylisoquinolines / Q000032:analysis / Q000737:chemistry*; D015394:Molecular Structure; D011522:Protons; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D031949:Thalictrum / Q000737:chemistry
D001060:Aporphines; D044182:Benzylisoquinolines; D011522:Protons; C081279:aporphine