Highly purified batches of pharmaceutical grade 1-deoxygalactonojirimycin compounds

1. A method of purifying an intermediate grade 1-deoxygalactonojirimycin compound, the method comprising:

i) performing a first crystallization comprising crystallizing intermediate grade 1-deoxygalactonojirimycin compound in a first mixture comprising water and a first C1 to C4 alcohol to give a first crystallized 1-deoxygalactonojirimycin compound;

ii) isolating the first crystallized 1-deoxygalactonojirimycin compound from the first mixture to give an isolated first crystallized 1-deoxygalactonojirimycin compound;

iii) performing a second crystallization comprising crystallizing the isolated first crystallized 1-deoxygalactonojirimycin compound in a second mixture comprising water and a second C1 to C4 alcohol to give a second crystallized 1-deoxygalactonojirimycin compound; and

iv) isolating the second crystallized 1-deoxygalactonojirimycin compound from the second mixture to give an active pharmaceutical ingredient (API) grade 1-deoxygalactonojirimycin compound.

2. The method of claim 1 , wherein the 1-deoxygalactonojirimycin compound comprises 1-deoxygalactonojirimycin derivatives and salts thereof.

3. The method of claim 2 , wherein the 1-deoxygalactonojirimycin derivative comprises N-alkyldeoxygalactonojirimycin.

4. The method of claim 2 , wherein the 1-deoxygalactonojirimycin derivative comprises migalastat, N-methyldeoxygalactonojirimycin, N-ethyldeoxygalactonojirimycin, N-propyldeoxygalactonojirimycin, N-butyldeoxygalactonojirimycin (lucerastat) or salt thereof.

5. The method of claim 2 , wherein the 1-deoxygalactonojirimycin derivatives comprises hydrochloride, hydrobromide, nitrate, perchlorate, phosphate, sulphate, formate, acetate, aconate, ascorbate, benzenesulphonate, benzoate, cinnamate, citrate, embonate, enantate, fumarate, glutamate, glycolate, lactate, maleate, malonate, mandelate, methane-sulphonate, naphthalene-2-sulphonate, phthalate, salicylate, sorbate, stearate, succinate, tartrate or toluene-p-sulphonate salt.

6. The method of claim 1 , wherein the first crystallization comprises:

admixing the intermediate grade 1-deoxygalactonojirimycin compound in water to produce a first 1-deoxygalactonojirimycin compound slurry or solution;

adding the first C1 to C4 alcohol to the first 1-deoxygalactonojirimycin compound slurry or solution to produce a second 1-deoxygalactonojirimycin compound slurry or solution at a first crystallization temperature for inducing crystallization; and

cooling the second 1-deoxygalactonojirimycin compound slurry or solution to a first isolation temperature to complete crystallization, providing the first mixture.

7. The method of claim 1 , wherein the isolating in ii) comprises:

filtering the first mixture to provide the first crystallized 1-deoxygalactonojirimycin compound;

washing the first crystallized 1-deoxygalactonojirimycin compound with the first C1 to C4 alcohol to provide a washed first crystallized 1-deoxygalactonojirimycin compound; and

optionally, drying the washed first crystallized 1-deoxygalactonojirimycin compound to give the isolated first crystallized 1-deoxygalactonojirimycin compound.

8. The method of claim 1 , wherein the second crystallization comprises:

admixing the isolated first crystallized 1-deoxygalactonojirimycin compound in water to produce a third 1-deoxygalactonojirimycin compound slurry or solution;

adding a first portion of the second C1 to C4 alcohol to the third 1-deoxygalactonojirimycin compound slurry or solution to produce a fourth 1-deoxygalactonojirimycin compound slurry or solution at a second crystallization temperature for inducing crystallization;

adding a second portion of the second C1 to C4 alcohol to the fourth 1-deoxygalactonojirimycin compound slurry or solution after a hold time; and

cooling the fourth 1-deoxygalactonojirimycin compound slurry or solution to a second isolation temperature to complete crystallization, providing the second mixture.

9. The method of claim 1 , wherein the isolating in iv) comprises:

filtering the second mixture to isolate the second crystallized 1-deoxygalactonojirimycin compound;

washing the second crystallized 1-deoxygalactonojirimycin compound with the second C1 to C4 alcohol; and

drying the washed second crystallized 1-deoxygalactonojirimycin compound to give the API grade 1-deoxygalactonojirimycin compound.

10. The method of claim 1 , wherein the first C1 to C4 alcohol is ethanol, the second C1 to C4 alcohol is ethanol, or both the first and the second C1 to C4 alcohol are ethanol.

11. The method of claim 1 , wherein the intermediate grade 1-deoxygalactonojirimycin compound, the isolated first crystallized 1-deoxygalactonojirimycin compound, or both, are admixed with an amount of water which is from about 1.0 to about 1.6 times the weight of the corresponding 1-deoxygalactonojirimycin compound.

12. The method of claim 1 , wherein the first crystallization temperature, the second crystallization temperature, or both, is within a range of from about 30° C. to about 70° C.

13. The method of claim 1 , wherein the first C1 to C4 alcohol is present in the first mixture in an amount from about 1 to about 11.4 times the weight of the intermediate 1-deoxygalactonojirimycin compound.

14. The method of claim 1 , wherein the second C1 to C4 alcohol is present in the second mixture in an amount from about 1 to about 11.4 times the weight of the isolated first crystallized 1-deoxygalactonojirimycin compound.

15. The method of claim 8 , wherein the first portion of the second C1 to C4 alcohol is about 1.8 to about 2.0 times the weight of the 1-deoxygalactonojirimycin compound present in the fourth 1-deoxygalactonojirimycin compound slurry or solution.

16. The method of claim 8 , wherein the second portion of the C1 to C4 alcohol is about 6.7 to about 8.4 times the weight of the 1-deoxygalactonojirimycin compound present in the fourth 1-deoxygalactonojirimycin compound slurry or solution.

17. The method of claim 6 , wherein the first isolation temperature is within a range from about 5° C. to about 35° C., or is about 20° C.

18. The method of claim 8 , wherein the second isolation temperature is within a range from about 5° C. to about 35° C., or is about 20° C.

19. The method of claim 6 , wherein the first C1 to C4 alcohol is added to the first 1-deoxygalactonojirimycin compound slurry or solution in an amount from about 1 to about 11.4 times the weight of the intermediate 1-deoxygalactonojirimycin compound over a period of time ranging from about 0 to about 65 minutes.

20. The method of claim 15 , wherein the first portion of C1 to C4 alcohol is added to the third 1-deoxygalactonojirimycin compound slurry or solution over a period from about 5 minutes to about 60 minutes.

21. The method of claim 8 , wherein the hold time is from about 5 minutes to about 60 minutes.

22. A method of purifying intermediate grade migalastat salt, the method comprising:

i) performing a first crystallization comprising crystallizing intermediate grade migalastat salt in a first mixture comprising water and a first C1 to C4 alcohol to give a first crystallized migalastat salt;

ii) isolating the first crystallized migalastat salt from the first mixture to give an isolated first crystallized migalastat salt;

iii) performing a second crystallization comprising crystallizing the isolated first crystallized migalastat salt in a second mixture comprising water and a second C1 to C4 alcohol to give a second crystallized migalastat salt; and

iv) isolating the second crystallized migalastat salt from the second mixture to give an active pharmaceutical ingredient (API) grade migalastat salt.

23. The method of claim 22 , wherein the first crystallization comprises:

admixing the intermediate grade migalastat salt in water to produce a first migalastat salt slurry or solution;

adding the first C1 to C4 alcohol to the first migalastat salt slurry or solution to produce a second migalastat salt slurry or solution at a first crystallization temperature for inducing crystallization; and

cooling the second migalastat salt slurry or solution to a first isolation temperature to complete crystallization, providing the first mixture.

24. The method of claim 22 , wherein the isolating in ii) comprises:

filtering the first mixture to provide the first crystallized migalastat salt;

washing the first crystallized migalastat salt with the first C1 to C4 alcohol to provide a washed first crystallized migalastat salt; and

optionally, drying the washed first crystallized migalastat salt to give the isolated first crystallized migalastat salt.

25. The method of claim 22 , wherein the second crystallization comprises:

admixing the isolated first crystallized migalastat salt in water to produce a third migalastat salt slurry or solution;

adding a first portion of the second C1 to C4 alcohol to the third migalastat salt slurry or solution to produce a fourth migalastat salt slurry or solution at a second crystallization temperature for inducing crystallization;

adding a second portion of the second C1 to C4 alcohol to the fourth migalastat salt slurry or solution after a hold time; and

cooling the fourth migalastat salt slurry or solution to a second isolation temperature to complete crystallization, providing the second mixture.

26. The method of claim 22 , wherein the isolating in iv) comprises:

filtering the second mixture to isolate the second crystallized migalastat salt;

washing the second crystallized migalastat salt with the second C1 to C4 alcohol; and

drying the washed second crystallized migalastat salt to give the API grade migalastat salt.

27. The method of claim 22 , wherein the first C1 to C4 alcohol is ethanol, the second C1 to C4 alcohol is ethanol, or both the first and the second C1 to C4 alcohol are ethanol.

28. The method of claim 22 , wherein the intermediate grade migalastat salt, the isolated first crystallized migalastat salt, or both, is admixed in an amount of water which is from about 1.0 to about 1.6 times the weight of the corresponding migalastat salt.

29. The method of claim 22 , wherein the first crystallization temperature, the second crystallization temperature, or both, is within a range of from about 30° C. to about 70° C.

30. The method of claim 23 , wherein the first isolation temperature is within a range from about 5° C. to about 35° C., or is about 20° C.