METHOD OF SYNTHESIS OF (2R,3S)-3-TERTIARY-BUTOXYCARBONYLAMINO- -2-HYDROXY-3-PHENYLPROPIONATE-4-ACETOXY-2α-BENZOYLOXY--5β,20- -EPOXY--1,7β,10β-TRIHYDROXY-9-OXO-TAX-11-ENE-13α-YL TRIHYDRATE Russian patent published in 1999 - IPC

FIELD: chemical technology, pharmacy. SUBSTANCE: invention relates to a method of synthesis of (2R,3S)-3-tert.-butoxy- -carbonylamino-2-hydroxy-3-phenylpropionate-4-acetoxy--2α- -benzoyloxy-5β,20-epoxy--1,7β,10β-trihydroxy-9-oxo-tax-11-ene--13α- -yl trihydrate that shows antitumor activity. Trihydrate has very low hygroscopicity as compared with other forms of this substance. Method of synthesis involves crystallization of (2R, 3S)-3-tert. -butoxycarbonylamino-2-hydroxy-3-phenyl- -propionate-4-acetoxy--2α-benzoyloxy--5β,, 20-epoxy--1,7β,10β- -trihydroxy-9-oxo-tax-11-ene-13α-yl in a mixture of water and aliphatic alcohol containing 1-3 carbon atoms at weight ratio = 2:1 followed by drying of prepared product, mainly at 40 C, under pressure, mainly at 4-7 kPa, in atmosphere of relative humidity mainly about 80%. Crystallization process is carried out preferably in the presence of ascorbic acid. EFFECT: improved method of synthesis. 5 cl, 2 ex