- Jan 24, 2019 -
Meropenem, one of the carbapenem antibiotics, has the following formula 1; and the chemical name thereof is (4R,5S,6S)-3-((3S,5S)-5-(dimethylcarbamoyl)pyrrolidin-3-ylthio)-6-((R)-1-hydroxyethyl) -4-methyl-7-oxo-1-azabicyclo[3.2.0]hept-2-ene-2-carboxylic acid. Meropenem is clinically used in a trihydrate form, i.e., meropenem trihydrate (meropenem·3H2O).  US 4,888,344 has disclosed a process for preparing a crystalline meropenem trihydrate, which comprises dissolving non-crystalline meropenem in water at 30°C, cooling the solution in a water bath (whereupon precipitation of a small amount of crystals), and adding acetone to the mixture to form a precipitate. As an improved process, WO 2007/031858 has disclosed a process for preparing meropenem trihydrate, which comprises dissolving meropenem or its hydrate in water in the presence of a base such as ammonia, optionally filtering through micron filter, adjusting the pH to 4.0 to 7.0 with an acid such as formic acid, and adding solvent (anti-solvent) to yield meropenem trihydrate.