Synthesis, Structure−Activity Relationships at the GABAA Receptor in Rat Brain, and Differential Electrophysiological Profile at the Recombinant Human GABAA Receptor of a Series of Substituted 1,2-Diphenylimidazoles
摘要:
A series of new 1,2-diphenylimidazole derivatives (la-x) were synthesized and evaluated for their ability to potentiate gamma-aminobutyric acid (GABA)-evoked currents in Xenopus laevis oocytes expressing recombinant human GABAA receptors. Many of these compounds enhanced GABA action with potencies (EC50 = 0.19-19,mu M) and efficacies (maximal efficacies of up to 640%) similar to or greater than those of anesthetics such as etomidate, propofol, and alphaxalone. Structure- activity relationship analysis revealed that the presence of an ester moiety in the imidazole ring was required for full agonist properties, while modifications made in the phenyl rings affected potency and efficacy, with ethyl 2-(4-bromophenyl)-l-(2,4-dichlorophenyl)-1H4-imidazolecarboxylate showing the highest potency. These compounds potentiated the [H-3]GABA binding to rat brain membranes, suggesting a site of interaction different from that of GABA. As for etomidate, mutation of asparagine-265 in the beta 2 subunit of the GABA(A) receptor into serine reduced the ability of derivative 1i to modulate the GABA function.
Synthesis, Structure−Activity Relationships at the GABAA Receptor in Rat Brain, and Differential Electrophysiological Profile at the Recombinant Human GABAA Receptor of a Series of Substituted 1,2-Diphenylimidazoles
摘要:
A series of new 1,2-diphenylimidazole derivatives (la-x) were synthesized and evaluated for their ability to potentiate gamma-aminobutyric acid (GABA)-evoked currents in Xenopus laevis oocytes expressing recombinant human GABAA receptors. Many of these compounds enhanced GABA action with potencies (EC50 = 0.19-19,mu M) and efficacies (maximal efficacies of up to 640%) similar to or greater than those of anesthetics such as etomidate, propofol, and alphaxalone. Structure- activity relationship analysis revealed that the presence of an ester moiety in the imidazole ring was required for full agonist properties, while modifications made in the phenyl rings affected potency and efficacy, with ethyl 2-(4-bromophenyl)-l-(2,4-dichlorophenyl)-1H4-imidazolecarboxylate showing the highest potency. These compounds potentiated the [H-3]GABA binding to rat brain membranes, suggesting a site of interaction different from that of GABA. As for etomidate, mutation of asparagine-265 in the beta 2 subunit of the GABA(A) receptor into serine reduced the ability of derivative 1i to modulate the GABA function.
Samarium(II) iodide induced reductive coupling of nitriles with nitro compounds
作者:Longhu Zhou、Yongmin Zhang
DOI:10.1039/a803077d
日期:——
The intermolecular and intramolecular reductive coupling of a cyano group with a nitro group induced by SmI2 was studied. Amidines and 2-aminoquinoline derivatives are prepared in good yields under neutral and mild conditions respectively.
Facile Synthesis of Amidines via the Intermolecular Reductive Coupling of Nitriles with Nitro Compounds Induced by Samarium(ii) Iodide
作者:Longhu Zhou、Yongmin Zhang
DOI:10.1039/a803011a
日期:——
The intermolecular reductive coupling of nitriles with nitro compounds induced by SmI2 was studied; amidine derivatives are prepared in good yields under neutral and mild conditions.
Low-Valent Titanium Induced Reductive Coupling of Nitriles with Nitro Compounds
作者:Longhu Zhou、Yongmin Zhang
DOI:10.1080/00397919808004430
日期:1998.9
Abstract The intermolecular and intramolecular reductivecoupling of a cyano group with a nitro group induced by a low-valenttitanium reagent prepared from TiCl4/Sm was studied. Amidines and 2-aminoquinolines derivatives are preparied in good yields under mild conditions respectively.
Reactions of Aryliminodimagnesium with Some<i>N</i>,<i>N</i>-Dimethylcarboxamides and Benzonitriles Affording Various Types of Amidines. Correction of Previous Results on Formamidine Formation from<i>N</i>,<i>N</i>-Dimethylformamide
Some symmetrical and unsymmetrical form- and benzamidines were prepared by the reaction of ArN(MgBr)2 with Ar’CN, HCONMe2 and related compounds in tetrahydrofurn.
DABCO-Promoted [3+2] Annulation for Efficient Synthesis of 1,2,5-Triaryl-1H-imidazoles from Substituted β-Nitrostyrenes and N-Arylbenzimidamides
作者:Cunde Wang、Yue Zhang、Xinyi Wan、Jianbo Gan
DOI:10.1055/a-1533-6872
日期:2021.12
An efficient approach to the synthesis of 1,2,5-trisubstituted imidazole derivatives was investigated via a DABCO-promoted formal [3+2]-annulation reaction of substituted N-arylbenzimidamides and substituted β-nitrostyrenes. The annulation reaction is implemented easily to afford the corresponding products in moderate to good yields with excellent regioselectivity.