Juglanone, a novel α-tetralonyl derivative with potent antioxidant activity from Juglans mandshurica

A novel alpha-tetralonyl derivative, juglanone, was isolated from the fresh unripe fruits of Juglans mandshurica. Its structure was determined by spectroscopic analyses and from chemical evidence. Juglanone exhibited significant antioxidant activity in assays for 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and superoxide dismutase-like activity with IC(50) values of 10.1 and 9.0 microM, respectively. It also showed moderate cytotoxic activity against HL-60 human myeloid leukemia with an IC(50) value of 19.7 microM.

Studies on the Constituents of Juglans Species. I. Structural Determination of (4S)- and (4R)-4-Hydroxy-.ALPHA.-tetralone Derivatives from the Fruit of Juglans mandshurica MAXIM. var. sieboldiana MAKINO

Four enantiomerically pure new alpha-tetralones, (4S)- and (4R)-5-hydroxy-4-methoxy-alpha-tetralones and (4S)- and (4R)-5,8-dihydroxy-4-methoxy-alpha-tetralones were isolated, together with five known ones, (4S)- and (4R)-4,8-dihydroxy-alpha-tetralones, (4S)-4,8-dihydroxy-5-methoxy-alpha-tetralone and (4S)- and (4R)-4-hydroxy-alpha-tetralones, from the fruit of Juglans mandshurica MAXIM. var. sieboldiana MAKINO. Their structures were established on the basis of spectral analysis. To the best of our knowledge, this is the first isolation of the (4R)-4-hydroxy-alpha-tetralone derivative from Juglans species.