Crystalline 4′-epidaunorubicin hydrochloride and use thereof
4′-epidaunorubicin hydrochloride is provided in a crystalline form which is stable and readily soluble. A process of producing the crystalline form includes crystallizing 4′-epidaunorubicin hydrochloride in a solvent system including (a) solvent A selected from C 1 and C 2 halogenated solvents and mixtures thereof, (b) solvent B selected from C 1 -C 5 straight and branched alcohols and mixtures thereof, and (c) solvent C selected from C 1 -C 5 straight and branched alcohols and mixtures thereof, wherein solvent C is selected to provide lower solubility to 4′-epidaunorubicin hydrochloride than solvent B. A method of producing an anthracycline using crystalline 4′-epidaunorubicin hydrochloride is also provided.
1. Crystalline 4′-epidaunorubicin hydrochloride characterized by its powder X-ray diffraction pattern comprising the following characteristic peaks:
Diffraction Angle 2(theta)
Relative intensity P (%)
5.13
40.00-46.00
7.64
29.00-33.50
12.18
23.50-26.00
16.77
18.90-20.70
17.00
24.50-26.90
19.86
54.00-62.00
21.82
25.80-28.25
22.58
100
23.03
30.00-32.00.