The solid residue thus obtained was then subjected to organosolv extraction [methanol-toluene, 1:2 (v/v)], with stirring at a constant temperature of 60 C for 6 h.
The solidresidue thus obtained was then subjected to organosolvextraction [methanol-toluene, 1:2 (v/v)], with stirring at aconstant temperature of 60 C for 6 h.