Studies on the Constituents of Aceraceae Plants. V. Two Diarylheptanoid Glycosides and an Arylbutanol Apiosylglucoside from Acer nikoense

Abstract

From the stem bark of Acer nikoense MAXIM. (Aceraceae), three glycosides were isolated, namely aceroside III (1), C₃₀H₄₀O₁₂, mp 138-141°C, [α]_D-98.4°, aceroside VI (2), C₂₅H₃₂O₈·1/2H₂O, mp 124-125°C, [α]_D-69.3°, and apiosylepirhododendrin (3), amorphous film (C₂₁H₃₂O₁₁), [α]_D-59.5°. On acid hydrolysis, 1 yielded acerogenin A (4), apiose, glucose, and a partially hydrolyzed product 2, while 3 afforded (+)-rhododendrol (11), apiose, and glucose. Inspection of the carbon-13 nuclear magnetic resonance (¹³C NMR) and the PRFT-NMR spectra of 1 and 3 disclosed that they are apiosyl-(1→6)-glucosides. The proton nuclear magnetic resonance (¹H NMR) spectral data of their permethylates (6 and 12) and the analytical data of methanolysis products of 6 and 12 established the structures of 1, 2 and 3 as acerogenin A 11-O-β-D-apiofuranosyl-(1→6)-β-D-glucopyranoside, acerogenin A 11-O-β-D-glucopyranoside and (+)-rhododendrol 2-O-β-D-apiofuranosyl-(1→6)-β-D-glucopyranoside, respectively.