LC-DAD-MS/SPE-NMR hyphenation. A tool for the analysis of pharmaceutically used plant extracts: identification of isobaric iridoid glycoside regioisomers from Harpagophytum procumbens.
LC-DAD-MS monitored fractionation of a Harpagophytum procumbens DC. (Pedaliaceae) root extract was combined with a hyphenated LC-DAD-MS/SPE-NMR technique, thus providing the spectral data needed for structure elucidation. This approach allowed the characterization of isobaric iridoid glycoside regioisomers present only as minor constituents. The analytes were identified as the (E/Z) pairs of 6'-O-(p-coumaroyl)harpagide (6'-PCHG) and 8-O-(p-coumaroyl)-harpagide (8-PCHG). The fact that 8-(Z)-PCHG constitutes a new natural product underlines the analytical power of this combined approach. Furthermore, derivatives 6'-(Z)- and 6'-(E)-PCHG are new constituents for H. procumbens.
Seger
Christoph
C
Institute of Pharmacy, Department of Pharmacognosy, Leopold Franzens University Innsbruck, Innrain 52, A-6020 Innsbruck, Austria.
Godejohann
Markus
M
Tseng
Li-Hong
LH
Spraul
Manfred
M
Girtler
Anny
A
Sturm
Sonja
S
Stuppner
Hermann
H
D006027:Glycosides / Q000302:isolation & purification* / Q000494:pharmacology; D031684:Harpagophytum / Q000737:chemistry*; D057889:Iridoid Glycosides; D039823:Iridoids / Q000302:isolation & purification* / Q000494:pharmacology; D007536:Isomerism; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D010936:Plant Extracts / Q000737:chemistry* / Q000494:pharmacology; D018517:Plant Roots / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry; D011714:Pyrans / Q000737:chemistry
D006027:Glycosides; D057889:Iridoid Glycosides; D039823:Iridoids; D010936:Plant Extracts; D011714:Pyrans; C033250:harpagide