NOVEL POLYMORPHIC FORM OF FERRIC MALTOL
The present application generally provides ferric maltol of formula I, and more particularly a crystalline form alfa of Ferric maltol, which is characterized by its PXRD pattern as illustrated herein. Corresponding methods for producing the ferric maltol disclosed herein are also provided.
1 . A crystalline Ferric maltol alfa form characterized by a PXRD pattern having peaks at 9.4, 12.7, 14.4, 15.2, 17.3, 19.8, 21.1, 23, 24.3° 2Θ±0.2° 2Θ.
2 . The crystalline Ferric maltol alfa form of claim 1 , characterized by a PXRD pattern as in FIG. 1 .
3 . A pharmaceutical composition, comprising a highly pure crystalline alfa form of Ferric maltol and one or more pharmaceutically acceptable excipients.
4 . The composition of claim 3 , wherein the crystalline alfa form of Ferric maltol is characterized as in claim 1 .
5 . A process for preparing the crystalline Ferric maltol alfa of claim 1 , comprising:
a) dissolving ferric maltol in at least one solvent;
b) evaporating the solvent at a temperature between about 70° C. and about 100° C.; and
c) isolating alfa Ferric maltol form therefrom.
6 . The process of claim 5 , wherein the ferric maltol is dissolved in a polar aprotic solvent selected from the group consisting of dimethylformamide, dimethylacetamide, dimethylsulfoxide, dichloromethane, and ethyl acetate.
7 . The process of claim 5 , wherein the ferric maltol is dissolved in an ether solvent selected from the group consisting of tetrahydrofuran, dioxane, methyl tertiary butyl ether, and diethyl ether.
8 . The process of claim 5 , wherein the ferric maltol is dissolved in a chloro solvent selected from the group consisting of dichloromethane, chloroform, and dichloroethane.
9 . The process of claim 5 , wherein the ferric maltol is dissolved in an alcoholic solvent selected from the group consisting of methanol, ethanol, isopropanol, and butanol.
10 . A process for preparing a crystalline form of Ferric maltol of formula I comprising:
a) dissolving maltol in water;
b) reacting the maltol solution with ferric chloride hexahydrate in water, in the presence of base sodium hydroxide;
c) adjusting the pH of the solution to about 7 pH;
d) distilling the reaction mixture under vacuum, below 55° C.;
e) dissolving residue in a chloro solvent selected from the group consisting of dichloromethane, chloroform, and dichloroethane;
f) filtering and evaporating the resulting solution under vacuum below 50° C. to obtain ferric maltol.