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US 8,299,258 B2Granted
Method of making piperidine derivatives
AssigneeCambrex Charles City, Inc.
InventorsGreg S. Buenger, Paul A. Jass, Kezia Peixoto Schutz
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Abstract
The present invention relates to a process for the preparation of piperidine derivatives including sufentanil, and their pharmaceutically acceptable salts, such as the citrate salt in which a quaternary ammonium (nosylate) salt of an appropriate piperidine is reacted with a corresponding 4-NO2 sulfonate ester to produce the desired piperidine derivative at a high purity.
Claims7
A method of making a 4-anilido-piperidine derivative of formula (4) comprising:
- reacting a piperidine ammonium salt of formula (2)
- with a 4-NO2 sulfonate ester of formula (3)
- where R is selected from —COOMe or —CH2OMe, and where R1 is selected from the following formulae (a), (b), (c), or (d):
- to produce the 4-anilido-piperidine derivative.
1 more element
Dependencies are inferred from the claim text.