20150291503 | PROCESS FOR THE PREPARATION OF TRAVOPROST - The subject of the invention is process the preparation of travoprost of formula (I) characterized by that the free acid of formula (II) is a.) activated with 2-chloro-1,3-dimethyl-imidazolinium chloride (DMC) and the resulting activated carboxylic acid intermediate is reacted with isopropyl alcohol, or b.) reacted with alkyl haloformate and the resulting mixed anhydride is reacted with isopropyl alcohol, or c.) activated with a straight or branched C1-8 dialkyl dicarbonate and reacted with isopropanol in the presence of water-free magnesium salt. | 10-15-2015 |