Bioactive substances from L.G. Don and their biological activities

Potassium lespedezate (3) and potassium isolespedezate (4) were isolated from the nyctinastic plant Lespedeza cuneata L.G. Don. These compounds (3 and 4) were quite effective for leaf-opening of the plant Cassia mimosoides L. at 8×10-7 mol/l. The interaction between the leaf-closing substance (2) and leaf-opening substances (3 and 4) shall govern in circadian rhythm of Cassia plants.