Extraction and Isolation.Aerial parts (623 g) was powdered and
extracted exhaustively by maceration at room temperature with CHCl3
to afford after removal of the solvent a dark brown syrup (21.5 g). The
extract (20 g) was fractionated by open column chromatography over
silica gel (380 g) using a gradient of CHCl3 in hexane, followed by
CHCl3Me2CO and Me2COMeOH in several proportions. Alto-gether, 89 eluates (200mL each one) were collected and combined as 20
fractions (120). Fraction 12 (2.3 g),