The Chemical Structure of Aceritannin (Acertannin). I. Determination of the Location of Two Galloyl Groups in Aceritannin

Abstract

Examinations were made on the chemical structure of aceritannin (acertannin), an oligogalloylated, crystalline tannin, C₂₀H₂₀O₁₃·2H₂O, m.p. 164∼166°, [α]¹²_D +20°(Me₂CO and EtOH, each), which was first isolated by Perkin and Uyeda from the leaves of Acer Ginnala MAXIM. It has now been proved that aceritannin should be formulated as 3, 6-di-O-galloyl-1, 5-anhydro-D-glucitol, i.e., no other than 1-deoxy derivative of 3, 6-di-O-galloyl-D-glucopyranose, a compound first isolated by Freudenberg (Ber., 52, 1238 (1919)) as one of the partial hydrolysis products of chebulinic acid, and later, unequivocally synthesized by Schmidt and Schach (Ann., 571, 29(1951)).