Minimizing E-factor in the continuous-flow synthesis of diazepam
<<Diazepam synthesis mechanism >> Without …
Benzodiazepines Mechanism of Action Andpharmacology ..
A number of studies have been performed, which are relevant to the question of whether diazepam has any action in organophosphate poisoning other than as an anticonvulsant. These studies have concentrated on various aspects of the cholinergic system, as well as the GABAergic system and cGMP concentrations. Very large doses of diazepam (20 mg/kg), increased the acetylcholine content of mouse brain (Tonkopii et al., 1978). In the corpus striatum and hippocampus of rats exposed to sarin and soman, diazepam decreased the magnitude of the elevations in choline concentrations, but not those of acetylcholine (Flynn & Wecker, 1986). On the basis of studies on the acetylcholine synthetic system of the mouse brain, Lundgren et al. (1987) suggested that in addition to observed effects on acetylcholine turnover, diazepam might have an effect on choline transport across the blood-brain barrier. Whether diazepam-induced effects on the GABAergic system are responsible for anticonvulsant activity in soman poisoning is unresolved (Lundy et al., 1978). An effect on soman-induced elevations in central nervous cGMP concentrations has been hypothesized as a mechanism of action of the benzodiazepin
Tonkopii VD, Sofronov GA, Aleksandriiskaya IE, & Brestkina LM (1978) [Mechanism of the effect of diazepam on acetylcholine concentration in mouse brain] (Russian). Biull Eksp Biol Med, 86: 38-40.
Benzodiazepines - Synthesis of Drugs - Drug Times
Johnson DD & Wilcox WC (1975) Studies on the mechanism of the protective and antidotal actions of diazepam in organophosphate poisoning. Eur J Pharmacol, 34: 127-132.
Gogerty JH, Griot RG, Habeck D, Iorio LC, & Houlihan WJ (1977) Synthesis and central nervous system evaluation of some 6-alkoxy-3H-1,4-benzodiazepin-2(IH)-ones. J Med Chem, 20: 952-956.
Various ways for the synthesis of diazepam from 2 …
A method for the synthesis of diazepam has been described (Sternbach et al., 1961). Benzoyl chloride reacts with p-chloroaniline to produce 2-amino-5-chlorobenzophenone. This is converted to the oxime with hydroxylamine. After cyclization with chloroacetyl chloride and ring enlargement with alkali treatment, 7-chloro-1,3-dihydro-5-phenyl-2H-1,4-benzodiazepin-2-one-4-oxide is reduced and methylated to diazepam.
This reaction is considered a modified Friedel-crafts acylation. The reaction is formally a series of electrophilic aromatic substitutions, with hydroxyl leaving groups picking up protons (1), however the lewis acid catalysis obviously plays a role in the mechanism. I think it increases the electrophilicity of the pthalic anhydride in the first step, and facilitates the elimination of the hydroxyl groups. For the mechanism without the involvment of the Zinc (II) chloride, see (1). Here is a mechanism emphasizing the role the lewis acid might play in catalyzing the reaction:
Synthesis of carbon-14 labeled 1,4-benzodiazepines
The mechanism of action of zolpidem is as a GABA A Agonist
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Experimental data permit the assumption that the mechanism of action of benzodiazepines lies in ..
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