Process for preparing crystalline .beta.-lactam monohydrate

Abstract

The invention provides a process for the preparation of the crystalline monohydrate form of the compound of the formula (I) ##STR1## which comprises the step of mixing a form of loracarbef, other than the crystalline monohydrate, such as the ethanol crystal, acetone crystal, crystalline dihydrate, acetonitrile crystal, methanol crystal, propanol crystal, ethyl acetate crystal, methylene chloride crystal, crystalline bis(DMF) and crystalline mono(DMF) form, in water at a temperature between about 30.degree. C. to about 60.degree. C., and preferably at a temperature between 40.degree. C. and 50.degree. C. Conversion may also be accomplished by exposing the loracarbef form to saturated steam at a temperature of between about 90.degree. to about 100.degree. C. Another aspect of the invention is the preparation of the above mentioned crystal forms by slurrying the bis(DMF) solvate form of the compound of formula (I) with the respective solvent.

Dependencies are inferred from the claim text.