Determination of the anxiolytic agent 8-chloro-6-(2-chlorophenyl)-4H-imidazo-[1,5-alpha] [1,4]-benzodiazepine-3-carboxamide in whole blood, plasma or urine by high-performance liquid chromatography.
A rapid, sensitive and specific high-performance liquid chromatographic (HPLC) assay was developed for the determination of 8-chloro-6-(2-chlorophenyl)-4H-imidazo-[1,5-alpha]-[1,4]-benzodiazepine-3-carboxamide [I] and its 4-hydroxy metabolite, 8-chloro-6-(2-chlorophenyl)-4-hydroxy-4H-imidazo-[1,5-alpha] [1,4]-benzodiazepine-3-carboxamide [II] in whole blood, plasma or urine. The assay for both compounds involves extraction into diethyl ether-methylene chloride (70:30) from blood, plasma, or urine buffered to pH 9.0. The overall recoveries of [I] and [II] are 92.0 +/- 5.4% (S.D.) and 90.3 +/- 4.9% (S.D.), respectively. The sensitivity limit of detection is 50 ng/ml of blood, plasma, or urine using a UV detector at 254 nm. The HPLC assay was used to monitor the blood concentration-time fall-off profiles, and urinary excretion profiles in the dog following single 1 mg/kg intravenous and 5 mg/kg oral doses, and following multiple oral doses of 100 mg/kg/day of compound [I].
Quinazolines and 1,4‐benzodiazepines. LXXXV syntheses of 3‐substituted lmidazo[1,5‐a] [1,4]benzodiazepines
1,4-Benzodiazepines having a leaving group in the 2-position were condensed with carbanions of 1,3-dicarbonyl compounds. The products obtained were converted to the title compounds by a sequence of steps involving hydrolytic decarboxylation, nitrosation, catalytic hydrogenation and condensation with an orthoester or an amide acetal. 
 
 
 
Oxidative condensation of the enediamine 12 with a variety of aldehydes also led to imidazo-benzodiazepines with various substituents in the 1-position.
The Interaction of Diazepam with Myoneural Blocking Agents
The interaction of diazepam with neuromuscular blocking agents was studied in patients and in several animal nerve-muscle preparations. This drug did not alter the recovery slope of blockade produced by d-tubocurarine, decamethonium, or gallamine. In higher doses diazepam produced a decrease in muscle contractions and blocked the actions of exogenously applied nicotine and acetylcholine in the superfused chick biventer cervicis nerve—muscle preparation. In low doses the commercially available drug given intra-arterially reversed the myoneural blockades produced by both depolarizing and nondepolarizing blockers. However, this property was due to the solvent system of the drug.