| abstract |
A process for obtaining substantially pure tetrahydrolipstatin (Orlistat) by a) extraction of a water miscible layer containing lipstatin with a water immiscible solvent, b) concentration of the water immiscible layer, c) extraction of the concentrate with a water miscible solvent, d) catalytic hydrogenation of the water miscible layer to afford tetrahydrolipstatin, e) filtration of the mixture from (d), f) treating with water or water miscible solvent, g) extraction with water immiscible solvent and concentration, h) affording tetrahydrolipstatin, i) treating with water miscible solvent to afford pharmaceutical pure tetrahydrolipstatin. |