TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Process: The usage of formic acid is 50-30 ml/g. The bi-phasic medium comprises water and an ester solvent. The process of obtaining (IV) is conducted at pH value of 7-9. The organic acid comprises acetic acid, propionic acid, butanoic acid, or oxalic acid. The ketone comprises acetone, methyl isobutyl ketone, or ethyl methyl ketone. The usage of acetic acid 1-3 ml/g. The process further comprises recovering (I) by concentrating a reaction mass, or by combining a reaction mass with an anti-solvent comprising water, an alkane, or an ether. The organic solvent comprises an ester, a nitrile, or a halogenated alkane, preferably ethyl acetate, butyl acetate, isopropyl acetate, acetonitrile, propionitrile, dichloromethane or chloroform. The anti-solvent comprises an ether. The purification steps are performed sequentially. The halogenated hydrocarbon comprises dichloromethane or chloroform. The ester solvent comprises ethyl acetate, n-butyl acetate or n-propyl acetate. The ether comprises diethyl ether, diisopropyl ether or methyl tert-butyl ether. ACTIVITY - Cytostatic. No details of tests for cytostatic activity are given.    MECHANISM OF ACTION - None given.    EXAMPLE - (4S,5R)-3-tert-Butoxycarbonyl-2,2-dimethyl-4-phenyl-5-oxazolidine carboxylic acid (54 g) and dichloromethane (1000 ml) were charged into a round bottom flask and stirred for dissolution. 4-Acetoxy-2alpha-benzoyloxy-5beta,20-epoxy-1beta,13alpha-dihydroxy-9-oxo-7beta,10beta-bis (2,2,2-trichloroethoxy carbonyloxy)-11-taxene (100 g), dimethylamino pyridine (13.6 g), and dicyclohexyldicarbamide (DCC) (46.1 g) were added to the solution and the mixture was stirred for 1 hour at 25-35 degrees C. DCC (11.5 g) was added and stirred for 30 minutes. The mixture was worked up to give 4-acetoxy-2alpha-benzoyloxy-5beta,20-epoxy-1-hydroxy-9-oxo-7beta,10beta-bis((2,2,2-tri-chloroethoxy)carbonyloxy)-11-taxen-13alpha-yl (4S,5R)-3-tert-butoxycarbonyl-2,2-dimethyl-4-phenyl-5-oxazolidine carboxylate (II). The compound (II) (122 g) and dichloromethane (488 ml) were charged into a round bottom flask at 26 degrees C and stirred for dissolution. The mixture was worked up to give the compound (II) in highly pure form (99 g; purity: 98.47%). Formic acid (1250 ml) and the compound (II) (50 g) were charged into a round bottom flask and stirred for 45-60 minutes at 25-30 degrees C. Ethyl acetate (1000 ml) was added, followed by water (2000 ml) and brine solution (1250 ml). The mixture was stirred for 10 minutes and the mixture was worked up to give 4-acetoxy-2alpha-benzoyloxy-5beta,20-epoxy-1-hydroxy-9-oxo-7beta,10beta-bis((2,2,2-trichloroethoxy)carbonyloxy)-11-taxen-13alpha-yl(2R,3S)-3-tert-butoxycarbonylamino-2-hydroxy-3-phenylpropionate (IV) (44 g; purity: 98.68%). The compound (IV) (30 g) and acetone (300 ml) were charged into a round bottom flask and stirred at 27 degrees C for dissolution. Zinc dust (13.5 g) and acetic acid (30 ml) were added and stirred for 30 minutes at 25-30 degrees C, until completion of the reaction. The mixture was worked up to give docetaxel (77%; purity: 99.48%).