Patent ID: 11952356
Assignee: SHANGHAI YUANXI MEDICINE CORP.
Field: Pharmaceuticals (Chemistry)
Classification: CPC A  C  Y | IPC C

Claim 4:
5. A method for preparing the crystalline form I according to claim 1, comprising:
dissolving 1,4-BIS[1,2-BENZISOSELENAZOL-3(2H)-one]-butane in a solvent S1, and adding an antisolvent S2 to give the crystalline form I;
wherein the solvent S1 is selected from dimethyl sulfoxide (DMSO) and a mixture of 1-10% acetone or tetrahydrofuran (v/v) in DMSO;
the antisolvent S2 is selected from water, acetonitrile, methyl tert-butyl ether (MTBE), isopropyl acetate, methanol and ethyl acetate, provided that when the solvent S1 is DMSO, the solvent S2 is not ethyl acetate.