One-step esterification of benzoylecgonine with dimethylformamide-dipropylacetal or dimethylformamide-diisopropylacetal in the presence of pyridine.
A simple procedure was developed to derivatize benzoylecgonine extracted from urine for subsequent confirmation by gas chromatography-mass spectrometry. The compound was esterified with dimethylformamide-dipropylacetal (DMF-DPA) or dimethylformamide-diisopropylacetal (DMF-DIPA) to the corresponding propyl and isopropyl esters. The optimum reaction condition was found to be heating the reaction mixture in the presence of pyridine at 100 degrees C for 30 min. The procedure is a one-step esterification followed by evaporation of excess reagents. When benzoylecgonine was extracted from urine using a solid-phase extraction technique and derivatized with this procedure, the compound was detected at a level as low as 10 ng/mL. Quantitation was linear over the concentration range 10-8000 ng/mL.
Division of Forensic Toxicology, Armed Forces Institute of Pathology, Rockville, Maryland 20706, USA.
B D
BD
Paul
C
C
Dreka
J L
JL
Summers
M L
ML
Smith
D000080:Acetals / Q000737:chemistry*; D003042:Cocaine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000652:urine; D004126:Dimethylformamide / Q000737:chemistry*; D004951:Esterification; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D011725:Pyridines / Q000737:chemistry*; D013237:Stereoisomerism
D000080:Acetals; D011725:Pyridines; C005618:benzoylecgonine; D004126:Dimethylformamide; D003042:Cocaine; C023666:pyridine