| 摘要 |
Three different polymorphs of Bromfenac sodium consist of Form 1 (sesquihydrate), Form II (monohydrate) and Form III (anhydrous). These polymorphs may be prepared and interconverted using crystallization/recrystallization, drying and/or hydration techniques. Form I may be prepared by crystallizingrecrystallizing amorphous Bromfenac sodium from a mixture of water, a dialkoxyalkane such as 1,2-dimethoxyethane and an anti-solvent such as an ether, preferably t-butyl methyl ether. Form II may be prepared by drying Form I under vacuum or by recrystallizing Form III from a mixture of water, a dialkoxyalkane such as 1,2-dimethoxyethane and an anti-solvent such as an ether, preferably t-butyl methyl ether to obtain an intermediate product and subsequently drying under vacuum. Form III may be prepared by crystallizing/recrystallizing amorphous Bromfenac sodium, Form I and/or Form II or mixtures thereof from a mixture of water and at least one alcohol, preferably ethanol. Form III may also be prepared by hydrating Form II.
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