The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 08, 2002
Filed:
Dec. 15, 2000
Hector F. DeLuca, Deerfield, WI (US);
Rafal R. Sicinski, Warsaw, PL;
Hazel Holden, Fitchburg, WI (US);
James Brian Thoden, Madison, WI (US);
Wisconsin Alumni Research Foundation, Madison, WI (US);
Abstract
A method of purifying 1&agr;-hydroxyvitamin D to obtain 1&agr;-hydroxyvitamin D in crystalline form. The method includes the steps of boiling a solvent selected from the group consisting of ethyl formate, ethyl acetate and a 2-propanol-hexane mixture under inert atmosphere, dissolving a product containing 1&agr;-hydroxyvitamin D to be purified in the solvent, cooling the solvent and dissolved product below ambient temperature for a sufficient amount of time to form a precipitate of 1&agr;-hydroxyvitamin D crystals, and recovering the 1&agr;-hydroxyvitamin D crystals. Petroleum ether is also added to the solvent after dissolving the product to be purified in the solvent.