Separation and identification of the transformation
products
Preparative TLC was carried out for separation of
considerable amounts of transformed products. The test
material dissolved in small volume of chloroform was
applied to silica gel plates. The plates were eluted using
solvent system A and the resulted separated zones were
scrapped off and extracted with chloroform. The solvent
was filtered off and evaporated to dryness in vacuum. This
leads to separation of two crude compounds I (150 mg)
and II (80 mg). Compounds were further purified
separately on Sephadex LH-20 column (2.5 X 60), using
methanol as an elution solvent. The purified transformed
products I and II were then analyzed by infrared (IR), UV,
FD-mass and NMR.