ABSTRACT
From the branches of Pittosporum senacia Putterlick (Pittosporaceae), two new triterpenoid saponins, senaciapittosides A and B (1, 2), were isolated. Their structures were elucidated by extensive analysis of one- and two-dimensional nuclear magnetic resonance spectroscopy, high-resolution electrospray ionization mass spectrometry (HR-ESIMS) and chemical evidence as 3-O-[ß-D-glucopyranosyl-(1 â 2)]-[α-L-arabinopyranosyl-(1 â 3)]-[α-L-arabinofuranosyl-(1 â 4)]-ß-D-glucuronopyranosyl oleanolic acid 28-O-ß-D-glucopyranosyl ester (1) and 3-O-[ß-D-glucopyranosyl-(1 â 2)]-[α-L-arabinopyranosyl-(1 â 3)]-[α-L-arabinofuranosyl-(1 â 4)]-ß-D-glucuronopyranosyl-22-O-α-L-arabinopyranosyl-21-acetoxy R1-barrigenol (2). Compound 2 presents an unusual glycosylation at C-22 of its aglycone.
Subject(s)
Plant Extracts/chemistry , Rosales/chemistry , Saponins/chemistry , Triterpenes/chemistry , Magnetic Resonance Spectroscopy , Molecular Structure , Saponins/isolation & purification , Spectrometry, Mass, Electrospray Ionization , Triterpenes/isolation & purificationABSTRACT
Three known cycloartane-type glycosides were isolated from the roots of two different species of Astragalus, A. glycyphyllos, A. sempervirens. The identification of these compounds were mainly achieved by 2D NMR spectroscopic techniques and FAB-MS. The results of our studies confirm that triterpene saponins from the cycloartane-type skeleton might be chemotaxonomically significant to the genus Astragalus.
