Isopropanol → Trityllosartan

Participants

Reaction Steps

Surprisingly it was found that if the suspension of Losartan potassium in isopropyl alcohol, obtained by deprotection of trityl Losartan, kept at a temperature of 25-30 degree for a period of 6-13 hours preferably 12 hours and is cooled slowly to a temperature of 0-5° C. in 2-12 hours, then the precipitated and dried crystals isolated in 82-92% yield are identical with the polymorphic Form I of Losartan potassium. The crystal form was found to be identical with the Polymorph Form I disclosed in the patent U.S. Pat. No. 5,608,075 by differential scanning calorimetry and X-Ray powder diffraction patterns studies.

Provenance & Evidence