Flunitrazepam, analysis

From the examination of structure-activity relationships, it has been concluded that a phenyl moiety at C-6 as well as a 4-hydroxypiperidine side-chain attached to C-3 of the pyridazine system is essential for anticonvulsant activity in this class of compounds [184], Compounds (54) and (55) have been found to have similar anticonvulsant profiles in animals (mice, rats and baboons) [165, and literature cited therein] and to represent potent broad-spectrum antiepileptic drugs. Their potency with regard to antagonizing seizures (induced by electro-shock or various chemicals) has been compared with standard anticonvulsants like carbamazepine and phenobarbitone [185, 186], A quantitative electroencephalographic analysis of (55) has been published [187]. From in vitro studies it has been concluded that the anticonvulsant activities of these compounds are not mediated by an enhancement of GABAergic transmission or by an interaction with benzodiazepine receptor sites [ 165,186,187], On the other hand, in vivo experiments showed that (54), at anticonvulsant doses, increases the affinity of flunitrazepam for its central receptor site [ 186], Investigations of (54) and (55) in a behavioural test predictive of antianxiety activity revealed a marked difference in the pharmacological profiles of these structurally closely related compounds the dichloro compound SR 41378 (55) has also been found to possess anxiolytic (anticonflict) properties [165],... 

Cahours, X., Cherkaoui, S., Rozing, G., and Veuthey, J. L. (2002). Microemulsion electrokinetic chromatography versus capillary electrochromatography-UV-mass spectrometry for the analysis of flunitrazepam and its major metabolites. Electrophoresis 23, 2320-2326. 

Eight BDZs among the most frequently encountered in forensic toxicology (clonazepam, desal-kylflurazepam, diazepam, flunitrazepam, lorazepam, midazolam, nordiazepam and oxazepam) were determined in whole blood after solvent extraction with butyl chloride and fast isocratic separation using a C18 (100 x 4.6 mm x 5 (tm) column [61]. The mobile phase was composed of phosphate buffer (35mM, pH 2.1) and acetonitrile (70 30, v/v) and the flow rate was 2mL/min. Within less than 4 min of analysis time, the analytes could be successfully determined starting from therapeutic concentrations. Using HPLC coupled with APCI-MS-MS, Rivera et al. [62] set up a method for the detection of 18 BDZ and metabolites after butyl chloride extraction at alkaline pH in 0.5mL... 

Macek et al. [120] developed a method to quantitate omeprazole in human plasma using liquid chromatography-tandem mass spectrometry. The method is based on the protein precipitation with acetonitrile and a reversed-phase liquid chromatography performed on an octadecylsilica column (55 x 2 mm, 3 /im). The mobile phase consisted of methanol-10 mM ammonium acetate (60 40). Omeprazole and the internal standard, flunitra-zepam, elute at 0.80 0.1 min with a total rim time 1.35 min. Quantification was through positive-ion made and selected reaction monitoring mode at m/z 346.1 —> 197.9 for omeprazole and m/z 314 —> 268 for flunitrazepam, respectively. The lower limit of quantification was 1.2 ng/ml using 0.25 ml of plasma and linearity was observed from 1.2 to 1200 ng/ml. The method was applied to the analysis of samples from a pharmacokinetic study. 

The instrument parameters (settings for the mass spectrometer) have been optimized in order to achieve the best possible response for the analysis of flunitrazepam, 7-aminoflunitrazepam, N-desmethyl-flunitrazepam and fluhnitrazepam-d7. 

M. Kollroser, C. Schober, Simultaneous analysis of flunitrazepam and its major metabolites in human plasma by LC-MS-MS, J. Phaim. Biomed. Anal., 28 (2002) 1173. 

The metabolic deactivation offlunitrazepam illustrated in Fig. 8-20 proceeds via demethylation and hydroxylation to give desmethylflunitrazepam, an active metabolite, and 3-hydroxyflunitrazepam. However, these two compounds are only important in blood analysis. The main metabolite in the urine is the 7-amino-derivative, which is sometimes present as the acetamido-compound. 7-Aminodesmethylflunitrazepam and 3-hydroxy-7-acetamidoflunitrazepam are also relevant flunitrazepam metabolites in the urine, but the starting substance itself does not normally appear. Approximately 10% of the dose is excreted via the bile with the feces. 

B. Urine. Collect a specimen if it is within 72 hours of suspected ingestion and freeze for analysis. (Note flunitrazepam [Rohypnol ] may be detected for up 96 hours.)... 

An autopsy of a 55-year-old woman indicated toxic levels of flunitrazepam, a finding that alone could not account for the woman s death. Further examination indicated a nutmeg-like smell of the stomach contents, with a blood analysis indicating 4.0 jig/ml of the compound myristicin (Stein et al. 2001). 

Similarly to dye standards, drug standards (3,4-methylenedioxy-Af-methylamphetamine, lysergic acid diethylamide, flunitrazepam) were resolved on a normal-phase TLC plate using chloroform/methanol (9 1). After drying, LIAD/ESI analysis was performed using the same procedure as for dye standards. All drugs were detected in positive-ion mode as [M+H]+ ions [54]. 

Quantitative Gas Chromatographic Analysis of Flunitrazepam in Human Serum with Electron-Capture Detection... 

LeBeau ML, Montgomery MA, Wagner JR et al (2000) Analysis of biofluids for flunitrazepam... 

---