title: Isolation and structure elucidation of cyclopeptide alkaloids from Ziziphus nummularia and Ziziphus spina-christi by HPLC-DAD-MS and HPLC-PDA-(HRMS)-SPE-NMR.
abstract: Seven cyclopeptide alkaloids were isolated from the stem bark of Ziziphus nummularia and Ziziphus spina-christi. Three previously undescribed compounds were identified: nummularine-U, spinanine-B and spinanine-C, together with the known compounds mauritine-F, nummularine-D, nummularine-E and amphibine-D. For their purification either semi-preparative HPLC with DAD and ESIMS detection or HPLC-PDA-(HRMS)-SPE-NMR was applied, together with conventional separation methods. Their structures were elucidated by spectroscopic means.
authors.affiliation: Natural Products & Food Research and Analysis, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium. Electronic address: Emmy.Tuenter@uantwerpen.be.
authors.forename: Emmy
authors.initials: E
authors.lastname: Tuenter
authors.affiliation: Natural Products & Food Research and Analysis, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium.
authors.forename: Kenn
authors.initials: K
authors.lastname: Foubert
authors.affiliation: Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, Universitetsparken 2, DK-2100, Copenhagen, Denmark.
authors.forename: Dan
authors.initials: D
authors.lastname: Staerk
authors.affiliation: Natural Products & Food Research and Analysis, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium.
authors.forename: Sandra
authors.initials: S
authors.lastname: Apers
authors.affiliation: Natural Products & Food Research and Analysis, Department of Pharmaceutical Sciences, University of Antwerp, Universiteitsplein 1, 2610 Antwerp, Belgium.
authors.forename: Luc
authors.initials: L
authors.lastname: Pieters
mesh_terms: D000470:Alkaloids / Q000737:chemistry* / Q000302:isolation & purification; D005591:Chemical Fractionation; D002851:Chromatography, High Pressure Liquid; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D015394:Molecular Structure; D010456:Peptides, Cyclic / Q000737:chemistry* / Q000302:isolation & purification; D024301:Plant Bark / Q000737:chemistry; D031957:Ziziphus / Q000737:chemistry* / Q000145:classification
chemical_list: D000470:Alkaloids; D010456:Peptides, Cyclic
keywords: Cyclopeptide alkaloids; Rhamnaceae; Ziziphus nummularia; Ziziphus spina-christi