New crystals of a benzoylbenzeneacetamide derivative
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- MEDICHEM
- Publication Date
- 2012-05-02
- Estimated Expiration
- Not applicable · inactive patent
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Abstract
Description
Background of the invention
[0001] Nepafenac (Compound I) is the internationally accepted name of 2-amino-3-benzoylphenylacetamide and has the empirical formula C 15 h 14 N 2 o 2 , and a molecular weight of 254.28.
[0002]
[0003] Nepafenac is an active non-steroidal anti-inflammatory drug with analgesic activity. In the United States, nepafenac is known under the name Nevanac TM It is marketed as a suspension and labeled for ophthalmic use.
[0004] The preparation of nepafenac and similar compounds is disclosed in US Patent No. 4,313,949. Specifically, Example 2 of US Patent No. 4,313,949 describes the synthesis of nepafenac, which was isolated as yellow needles after crystallization from isopropanol.
[0005] However, it is well known that needle-shaped crystals have high electrostatic properties, which cause processability problems, ie, sticking, looseness, difficulty in filtration, etc. caused by static electricity. Also, such crystals of electrostatic nature...