METHOD OF PREPARING 1,3-OXAZOLIDINE-5- CARBOXYLIC ACIDS (VARIANTS) Russian patent published in 1998 - IPC

FIELD: medicine. SUBSTANCE: 1,3- oxazolidine-5-carboxylic acids are used for preparing taxol, taxoter or analogues thereof which have antileukemic properties. Present invention discloses method of preparing 1,3-oxazolidinecarboxylic acid of general formula (I): wherein Ar is phenyl; R₁ is benzoyl or alkoxycarbonyl with C₁-C₈ alkoxy moiety; Ph is phenyl optionally substituted by C₁-C₄ alkoxy, from compound of formula II wherein X is residue of optically active organic base, or residue OR in which R is C₁-C₄ alkyl optionally substituted phenyl, by cyclization thereof in organic solvent in the presence of oxidizing agent followed by hydrolysis or saponification of the resulting product of formula III. Present invention also describes second method of preparing compounds of general formula I by reacting ether of formula IV with phenylisoserine derivative of formula V in organic solvent in the presence of oxidizing agent followed by saponification of the resulting ester of formula VI in alkaline medium. EFFECT: improved properties of the title compounds. 9 cl, 4 ex