Two new triterpenoid saponins from Pittosporum senacia Putterlick (Pittosporaceae)

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‐β‐d ‐glucopyranosyl‐(1 → 2)]‐α‐l ‐arabinopyranosyl‐(1 → 3)]‐α‐l ‐arabinofuranosyl‐(1 → 4)]‐β‐d ‐glucuronopyranosyl oleanolic acid 28‐O‐β‐d ‐glucopyranosyl ester (1) and 3‐O‐β‐d ‐glucopyranosyl‐(1 → 2)]‐α‐l ‐arabinopyranosyl‐(1 → 3)]‐α‐l ‐arabinofuranosyl‐(1 → 4)]‐β‐d ‐glucuronopyranosyl‐22‐O‐α‐l ‐arabinopyranosyl‐21‐acetoxy R1‐barrigenol (2). Compound 2 presents an unusual glycosylation at C‐22 of its aglycone. Copyright © 2012 John Wiley & Sons, Ltd.