Studies on Aldose Reductase Inhibitors from Natural Products. V. Active Components of Hachimi-jio-gan (Kampo Medicine)

Abstract

Aldose reductase (AR) inhibitory activity-directed fractionation of Hachimi-jio-gan has led to the isolation of 5-(hydroxymethyl)-2-furfuraldehyde (1) and ellagic acid (2). 2 was reported to be a strong AR inhibitor in this series of study on AR inhibitors, but 1 is the first isolation from a natural source and as an AR inhibitor. The AR inhibitory activity of the eight crude drugs which constitute Hachimi-jio-gan, and a comparison of their components by TLC, were also examined. Corni Fructus was found to be one of the important drugs having an AR inhibitory effect, and only in this drug were compounds 1 and 2 contained together. © 1993, The Pharmaceutical Society of Japan. All rights reserved.