1.
J Pharm Sci
; 65(9): 1305-9, 1976 Sep.
Artigo
em Inglês
| MEDLINE
| ID: mdl-966143
RESUMO
GLC and NMR methods are described for the determination of four possible isomeric impurities in the novel anti-inflammatory agent benoxaprofen. The 2- and 3-chlorophenyl isomers were determined by GLC after alkaline hydrolysis and subsequent methylation. A rapid NMR procedure, using the lanthanide shift reagent tris- (1, 1, 1, 2, 2, 3, 3-heptafluoro- 7, 7-dimethyl- 4, 6-octanedionato)-europium, was developed for the 6- and 7- (alpha-methylacetic acid) isomers. Similar methodolology, with tris-(3-heptafluorobutyryl-d-camphorato)europium, enabled the determination of the enantiomer ratio for benoxaprofen. For the positional isomers, the limits of detection were 0.05% by GLC and 0.2% by NMR.