Characterisation of alkaloids from some Australian Stephania (Menispermaceae) species

• Published in: Phytochemistry (Oxford) 2003-07, Vol.63 (6), p.711-720
• Main Authors: Blanchfield, Joanne T, Sands, Donald P.A, Kennard, Colin H.L, Byriel, Karl A, Kitching, William
• Format: Article
• Language: English
• Subjects: Alkaloid; Alkaloids - analysis; Australia; Biological and medical sciences; Chemical constitution; Fundamental and applied biological sciences. Psychology; Magnetic Resonance Spectroscopy; Menispermaceae; Menispermaceae - chemistry; Models, Molecular; Molecular Structure; NMR data; Plant Leaves; Plant physiology and development; Plant Stems - chemistry; Plant Tubers - chemistry; Species Specificity; Staphania bancroftii; Stephania aculeata; Stephania japonica
• ISSN: 0031-9422; 1873-3700
• DOI: 10.1016/S0031-9422(03)00240-1

Complete and unambiguous NMR analysis of several benzylisoquinoline alkaloids including (−)-ayuthianine (4) and the X-ray crystal structure of the methiodide derivative of (−)-amurine (9). Chemical investigations of some Stephania species native to Australia and reportedly employed by Aboriginal people as therapeutic agents, are described. The alkaloids from the forest vines Stephania bancroftii F.M. Bailey and S. aculeata F.M. Bailey (Menispermaceae) have been isolated and characterised. The major alkaloids in the tuber of the former species are (−)-tetrahydropalmatine and (−)-stephanine, whereas these are minor components in the leaves, from which a C-7 hydroxylated aporphine has been identified. The major tuber alkaloids in S. aculeata are (+)-laudanidine, and the morphinoid, (−)-amurine, whose absolute stereochemistry has been established by X-ray structural analysis of the methiodide derivative. No significant levels of alkaloids were detected in S. japonica. Complete and unambiguous 1H and 13C NMR data are presented for these alkaloids.