abstract |
FIELD: chemistry. n SUBSTANCE: invention relates to a process for the preparation of travoprost of formula (I), characterized in that the compound of formula (II) is stereoselectively reduced with a reducing agent of the borane type in the presence of a chiral catalyst, the resulting compound of formula (III) is crystallized if desired, the lactone group of the compound of formula (III) is reduced with diisobutylaluminium hydride, the p-phenylbenzoyl protecting group of the thus obtained compound of formula (IV) is removed by methanolysis, the resulting triol of formula (V), if desired after crystallization and are converted into an acid of formula (VI) by Wittig reaction, and an acid is then esterified in a cyclic tertiary amide type solvent with isopropyl iodide. n EFFECT: method has a higher selectivity and better yield. n 28 cl, 7 dwg, 6 ex |