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:
Apr. 20, 2010
Filed:
Dec. 29, 2005
Andrzej Kutner, Warsaw, PL;
Michal Chodyński, Pruszków, PL;
Teresa Ryznar, Warsaw, PL;
Hanna Fitak, Warsaw, PL;
Jerzy Winiarski, Warsaw, PL;
Bartlomiej Górecki, Warsaw, PL;
Agnieszka Burzyńska, Zawiercie, PL;
Wieslaw Szelejewski, Warsaw, PL;
Andrzej Kutner, Warsaw, PL;
Michal Chodyński, Pruszków, PL;
Teresa Ryznar, Warsaw, PL;
Hanna Fitak, Warsaw, PL;
Jerzy Winiarski, Warsaw, PL;
Bartlomiej Górecki, Warsaw, PL;
Agnieszka Burzyńska, Zawiercie, PL;
Wieslaw Szelejewski, Warsaw, PL;
Instytut Farmaceutyczny, Warsaw, PL;
Abstract
A process for the preparation of a pharmaceutical-grade anhydrous calcipotriol comprising: (a) dissolving crude calcipotriol having a water content of X% by weight in a first solvent or in a mixture of two or more first solvents, said first solvent or said mixture of two or more first solvents forming an azeotropic system with water, to obtain a solution of crude calcipotriol; (b) obtaining an intermediate calcipotriol by (i) placing said solution of crude calcipotriol under a reduced pressure and evaporating, if X is greater than or equal to 1, or (ii) crystallizing, if X is lower than 1; and (c) re-dissolving said intermediate calcipotriol in a second solvent or a mixture of two or more second solvents, said second solvent being anhydrous, and crystallizing at least once to obtain pharmaceutical-grade anhydrous calcipotriol.