Method for preparing crystalline cefadroxil monohydrate
Patent 4898938 Issued on February 6, 1990. Estimated Expiration Date: 
August 3, 2007. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
August 3, 2007. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesProcess for the preparation of the crystalline monohydrate of 7-[D-amino-(p-hydroxyphenyl]acetamido)-3-methyl-3-cephen-4-carboxylic acid Cephadroxil monohydrate Patent #: 4504657 InventorApplicationNo. 080999 filed on 08/03/1987US Classes:540/230Alkyl, hydroxyalkyl, alkoxyalkyl or alkanoyloxyalkyl bonded directly to 3 positionExaminersPrimary: Rizzo, Nicholas S.Attorney, Agent or FirmInternational ClassesC07D 501/22A61K 031/545 AbstractThe invention relates to a method for preparing crystalline cefadroxil monohydrate.According to such a method a cefadroxil solvate is slurried with isopropyl alcohol containing less 6% to 18% of water at a temperature between +45° to +55° C.: the crystalline cefadroxil monohydrate is isolated by filtration.Some of the cefadroxil solvates which can be used are novel: they are prepared by adding dimethylacetamide, N-methyl-2-pyrrolidone or monomethylformamide to an aqueous solution of cefadroxil at a pH between 5.5 and 6. |
| ||||||||||||||
