High purity bases of 3,3-diphenylpropylamino monoesters

1. A pharmaceutical formulation comprising a compound of Formula I,

in which A is deuterium or hydrogen, R is selected from the group consisting of C 1-6 -alkyl, C 3-10 -cycloalkyl and phenyl, which may each be substituted with C 1-3 -alkoxy, fluorine, chlorine, bromine, iodine, nitro, amino, hydroxyl, oxo, mercapto or deuterium and where the C-atom marked with a star “*” may be present in the (R)-configuration, the (S)-configuration or as a mixture of the (R)-configuration and the (S)-configuration,

and a pharmaceutically active carrier,

wherein the compound of Formula I is present as a free base with a salt content of below 10 wt % and wherein the compound of Formula I is present in a degree of purity of above 97 percent by weight and the pharmaceutical formulation comprises a therapeutically effective amount of the free base of the compound of Formula I.

2. The pharmaceutical formulation according to claim 1 , wherein R is selected from the group methyl, ethyl, isopropyl, 1-propyl, 1-butyl, 2-butyl, tertiary-butyl, iso-butyl, pentyl and hexyl.

3. The pharmaceutical formulation according to one claim 1 , wherein the compound is 2-[3-(1,1-diisopropylamino)-1-phenylpropyl]-4-(hydroxymethyl)phenyl isobutyrate.

4. The pharmaceutical formulation according to claim 1 , wherein the C-atom marked with “*” is present in the (R)-configuration.

5. The pharmaceutical formulation according to claim 1 , wherein the compound is (R)-2-[3-(1,1-diisopropylamino)-1-phenylpropyl]-4-(hydroxymethyl)phenyl isobutyrate (fesoterodine).

6. The pharmaceutical formulation according to any one of the claims 1 - 5 , wherein the pharmaceutically acceptable carrier is a polymer.

7. The pharmaceutical formulation according to an one of claims 1 - 5 having a stabilization factor of at least 2 for the compound of Formula I in the pharmaceutical formulation, wherein the stabilization factor is determined by the division of the average monthly drop in concentration of the compound of Formula I during storage as oil and in the absence of the pharmaceutically acceptable carrier at 5° C. by the average monthly drop in concentration of the corresponding compound of Formula I during storage in the pharmaceutical formulation at 5° C.

8. The pharmaceutical formulation according to claim 7 , wherein the formulation exhibits a pH value of 3.0-6.0.

9. The pharmaceutical formulation according to claim 8 , wherein the pharmaceutical formulation is suitable for transdermal or transmucosal delivery.

10. The pharmaceutical formulation according to claim 9 , wherein the pharmaceutical formulation contains a polymer layer and wherein the compound of Formula I is either dissolved or dispersed in the polymer layer.

11. The pharmaceutical formulation according to claim 10 , wherein the polymer layer contains a contact adhesive, which makes the attachment of the pharmaceutical composition to the skin or the mucous membrane of the patient possible.

12. The pharmaceutical formulation according to claim 11 , wherein the polymer layer contains a contact adhesive, which makes the attachment of the pharmaceutical composition to the skin of the patient possible and which is chosen from the group consisting of silicone, acrylate, SXS-, PIB- and EVA based contact adhesives.

13. The pharmaceutical formulation according to claim 12 , wherein the pharmaceutical formulation is a transdermal therapeutic system of the active ingredient-in-adhesive type.

14. The pharmaceutical formulation according to claim 1 , which is a dosing unit that contains at least 3 mg of the compound of Formula I.

15. The pharmaceutical formulation according to claim 5 , which is a dosing unit that contains at least 3 mg of (R) 2-[3-(1,1-Diisopropylamino)-1-phenylpropyl]-4-(hydroxymethyl)phenyl isobutyrate (fesoterodine).

16. A kit containing a pharmaceutical formulation according to any one of claims 1 or 5 , and a drying agent.