Acerogenin B (3), C19H22O3, mp 179°, [α]23D±0°, a new diarylheptanoid of diphenyl ether type, was isolated from an acid hydrolysate of the glycoside mixture extracted from the bark of Acer nikoense MAXIM. The structure of acerogenin B (3) was established as formula 3 in Chart 1 on the basis of the spectral data and chemical correlation with acero-genin A (2). Acerogenin B (3) was considered to be a racemic compound in view of the optical inactivity of 3 and its derivatives (4 and 10).
