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Base-Mediated Claisen Rearrangement of CF 3-Containing Bisallyl Ethers. Molecules 2021; 26:molecules26144365. [PMID: 34299639 PMCID: PMC8304132 DOI: 10.3390/molecules26144365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 07/05/2021] [Accepted: 07/14/2021] [Indexed: 11/27/2022] Open
Abstract
We have previously clarified that the strongly electron-withdrawing CF3 group nicely affected the base-mediated proton shift of CF3-containing propargylic or allylic alcohols to afford the corresponding α,β-unsaturated or saturated ketones, respectively, which was applied this time to the Claisen rearrangement after O-allylation of the allylic alcohols with a CF3 group, followed by isomerization to the corresponding allyl vinyl ethers via the proton shift, enabling the desired rearrangement in a tandem fashion, or in a stepwise manner, the latter of which was proved to have attained an excellent diastereoselectivity with the aid of a palladium catalyst.
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2
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Insights into the chemistry and therapeutic potential of furanones: A versatile pharmacophore. Eur J Med Chem 2019; 171:66-92. [DOI: 10.1016/j.ejmech.2019.03.021] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 02/09/2019] [Accepted: 03/07/2019] [Indexed: 02/06/2023]
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3
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An improved solvent-free system for the microwave-assisted decarboxylation of malonate derivatives based on the use of imidazole. Tetrahedron 2015. [DOI: 10.1016/j.tet.2015.09.012] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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4
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Nenajdenko VG, Muzalevskiy VM, Shastin AV. Polyfluorinated ethanes as versatile fluorinated C2-building blocks for organic synthesis. Chem Rev 2015; 115:973-1050. [PMID: 25594605 DOI: 10.1021/cr500465n] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Valentine G Nenajdenko
- Department of Chemistry, Moscow State University , Leninskie Gory, Moscow 119992, Russia
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5
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Garro Martinez JC, Vega-Hissi EG, Andrada MF, Estrada MR. QSAR and 3D-QSAR studies applied to compounds with anticonvulsant activity. Expert Opin Drug Discov 2014; 10:37-51. [DOI: 10.1517/17460441.2015.968123] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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6
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Mydock-McGrane L, Rath NP, Covey DF. Synthesis of a smoothened cholesterol: 18,19-di-nor-cholesterol. J Org Chem 2014; 79:5636-43. [PMID: 24823889 PMCID: PMC4076041 DOI: 10.1021/jo500813n] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2014] [Indexed: 11/29/2022]
Abstract
Herein, we report the first synthesis of a demethylated form of cholesterol (18,19-di-nor-cholesterol), in which the C18 and C19 methyl groups of the β-face were eliminated. Recent molecular simulations modeling 18,19-di-nor-cholesterol have suggested that cholesterol's opposing rough β-face and smooth α-face play necessary roles in cholesterol's membrane condensing abilities and, additionally, that specific facial preferences are displayed as cholesterol interacts with different neighboring lipids and transmembrane proteins. Inspired by these poorly characterized biochemical interactions, an extensive 18-step synthesis was completed as part of a collaborative effort, wherein synthesizing a "smoothened" cholesterol analogue would provide a direct way to experimentally measure the significance of the β-face methyl groups. Starting from known perhydrochrysenone A, the synthesis of 18,19-di-nor-cholesterol was accomplished with an excellent overall yield of 3.5%. The use of the highly stereoselective Dieckmann condensation and the employment of Evans' chiral auxiliary were both key to ensuring the success of this synthesis.
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Affiliation(s)
- Laurel Mydock-McGrane
- Department
of Developmental Biology, Anesthesiology, and Psychiatry, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Nigam P. Rath
- Department
of Chemistry and Biochemistry, University
of Missouri−St. Louis, St. Louis, Missouri 63121, United States
| | - Douglas F. Covey
- Department
of Developmental Biology, Anesthesiology, and Psychiatry, Washington University School of Medicine, St. Louis, Missouri 63110, United States
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7
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Yamazaki T, Umetani H, Kitazume T. CuCN and Trimethylsilyl Chloride-Catalyzed Regiospecific Grignard Reactions to CF3-Containing Allylic Derivatives. Isr J Chem 2013. [DOI: 10.1002/ijch.199900025] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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8
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Ichikawa T, Kawasaki-Takasuka T, Yamada S, Yamazaki T, Kubota T. Construction of chiral trifluoromethylated materials by combination of stereochemically predictable SN2′ reaction and Ireland-Claisen rearrangement. J Fluor Chem 2013. [DOI: 10.1016/j.jfluchem.2012.10.013] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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9
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Więckowski K, Sałat K, Bytnar J, Bajda M, Filipek B, Stables JP, Malawska B. Search for anticonvulsant and analgesic active derivatives of dihydrofuran-2(3H)-one. Bioorg Med Chem 2012; 20:6533-44. [PMID: 23010454 DOI: 10.1016/j.bmc.2012.08.037] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Revised: 07/25/2012] [Accepted: 08/08/2012] [Indexed: 11/25/2022]
Abstract
A series of derivatives of dihydrofuran-2(3H)-one (γ-butyrolactone, GBL) was synthesized and tested for anticonvulsant, neurotoxic and analgesic activity. In the anticonvulsant screening 10 lactones were effective in the maximal electroshock test (MES) at the highest doses (300 and 100 mg/kg, 0.5 h, ip, mice). Statistical analysis showed correlation between the anticonvulsant activity and relative lipophilicity parameters determined by experimental and computational methods (R(M0), ClogP and MlogP). Preliminary antinociceptive evaluation of selected derivatives revealed strong analgesic activity. The majority of the tested compounds showed high efficacy in animal models of acute pain (hot plate and writhing tests) and strong local anesthetic activity (modified tail immersion test). The obtained ED(50) values were comparable with such analgesics as acetylsalicylic acid and morphine.
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Affiliation(s)
- Krzysztof Więckowski
- Department of Physicochemical Drug Analysis, Jagiellonian University, Medical College, Medyczna 9, PL 30-688 Kraków, Poland
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Analgesic, anticonvulsant and antioxidant activities of 3-[4-(3-trifluoromethyl-phenyl)-piperazin-1-yl]-dihydrofuran-2-one dihydrochloride in mice. Pharmacol Biochem Behav 2011; 101:138-47. [PMID: 22227221 DOI: 10.1016/j.pbb.2011.12.014] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2011] [Revised: 12/18/2011] [Accepted: 12/19/2011] [Indexed: 11/21/2022]
Abstract
Recently we have shown that 3-[4-(3-trifluoromethyl-phenyl)-piperazin-1-yl]-dihydrofuran-2-one dihydrochloride (LPP1) is an antinociceptive and local anesthetic agent in rodents. Below an extended study of the pharmacological activity of LPP1 is described. In vitro LPP1 has no affinity for GABA(A), opioidergic μ and serotonergic 5-HT(1A) receptors. The total antioxidant capacity of LPP1 (1-10mM) measured as ABTS radical cation-scavenging activity showed that LPP1 has dose-dependent antioxidant properties in vitro. Low plasma concentration of this compound detected by means of HPLC method 30min after its intraperitoneal administration suggests a rapid conversion to metabolite(s) which may be responsible for its analgesic and anticonvulsant activities in vivo. In vivo the compound's influence on the electroconvulsive threshold and its activity in the maximal electroshock seizure test (MES) were evaluated. The results demonstrated that LPP1 had an anticonvulsant activity in the MES model (ED(50)=112mg/kg) and at a dose of 50mg/kg was able to elevate the electroconvulsive threshold for 8mA as compared to the vehicle-treated mice. The analgesic activity of LPP1 was investigated in the acetic acid-induced writhing test in two groups of mice: animals with sensory C-fibers ablated, and mice with C-fibers unimpaired. It proved the potent activity of this compound in both groups (approximately 85% as compared to the vehicle-treated mice). The adverse effects of LPP1 were evaluated as acute toxicity (LD(50)=747.8mg/kg) and motor coordination impairments in the rotarod and chimney tests. The results from these tests show that LPP1 at doses higher than 100mg/kg is likely to impair the motor performance of experimental animals. Concluding, LPP1 is an analgesic and anticonvulsant compound which has antioxidant properties in vitro. Further studies are necessary to assess whether the antioxidant activity and the receptor profiling demonstrated in vitro can be confirmed for its metabolite(s) that are formed in vivo.
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11
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Sałat K, Filipek B, Więckowski K, Malawska B. Analgesic activity of 3-mono-substituted derivatives of dihydrofuran-2-one in experimental rodent models of pain. Pharmacol Rep 2009; 61:807-18. [DOI: 10.1016/s1734-1140(09)70136-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2008] [Revised: 09/09/2009] [Indexed: 10/25/2022]
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12
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Keeling SP, Campbell IB, Coe DM, Cooper TW, Hardy GW, Jack TI, Jones HT, Needham D, Shipley TJ, Skone PA, Sutton PW, Weingarten GA, Macdonald SJ. Efficient synthesis of an α-trifluoromethyl-α-tosyloxymethyl epoxide enabling stepwise double functionalisation to afford CF3-substituted tertiary alcohols. Tetrahedron Lett 2008. [DOI: 10.1016/j.tetlet.2008.06.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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13
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Araújo AC, Nicotra F, Costa B, Giagnoni G, Cipolla L. Fructose-fused γ-butyrolactones and lactams, synthesis and biological evaluation as GABA receptor ligands. Carbohydr Res 2008; 343:1840-8. [DOI: 10.1016/j.carres.2008.03.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2008] [Revised: 03/07/2008] [Accepted: 03/09/2008] [Indexed: 01/17/2023]
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14
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Chen Q, Qing FL. Stereoselective construction of the 1,1,1-trifluoroisopropyl moiety by asymmetric hydrogenation of 2-(trifluoromethyl)allylic alcohols and its application to the synthesis of a trifluoromethylated amino diol. Tetrahedron 2007. [DOI: 10.1016/j.tet.2007.09.013] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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15
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Paryzek Z, Skiera I. SYNTHESIS AND CLEAVAGE OF LACTONES AND THIOLACTONES. APPLICATIONS IN ORGANIC SYNTHESIS. A REVIEW. ORG PREP PROCED INT 2007. [DOI: 10.1080/00304940709356015] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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16
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Kalueff AV. Mapping convulsants' binding to the GABA-A receptor chloride ionophore: a proposed model for channel binding sites. Neurochem Int 2007; 50:61-8. [PMID: 16959376 PMCID: PMC1939818 DOI: 10.1016/j.neuint.2006.07.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2006] [Revised: 07/05/2006] [Accepted: 07/07/2006] [Indexed: 02/01/2023]
Abstract
Gamma-aminobutyric acid (GABA) type A receptors play a key role in brain inhibitory neurotransmission, and are ligand-activated chloride channels blocked by numerous convulsant ligands. Here we summarize data on binding of picrotoxin, tetrazoles, beta-lactams, bicyclophosphates, butyrolactones and neurotoxic pesticides to GABA-A ionophore, and discuss functional and structural overlapping of their binding sites. The paper reviews data on convulsants' binding sensitivity to different point mutations in ionophore-lining second trans-membrane domains of GABA-A subunits, and maps possible location of convulsants' sites within the chloride ionophore. We also discuss data on inhibition of glycine, glutamate, serotonin (5-HT3) and N-acetylcholine receptors by GABA-A channel blockers, and examine the applicability of this model to other homologous ionotropic receptors. Positioning various convulsant-binding sites within ionophore of GABA-A receptors, this model enables a better understanding of complex architectonics of ionotropic receptors, and may be used for developing new channel-modulating drugs.
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Affiliation(s)
- A V Kalueff
- Laboratory of Clinical Science, Building 10, Room 3D41, National Institute of Mental Health (NIMH), NIH, 10 Center Dr. MSC 1264, Bethesda, MD 20892-1264, USA.
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17
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Gonzales EB, Bell-Horner CL, de la Cruz MAM, Ferrendelli JA, Covey DF, Dillon GH. Enantioselectivity of alpha-benzyl-alpha-methyl-gamma-butyrolactone-mediated modulation of anticonvulsant activity and GABA(A) receptor function. J Pharmacol Exp Ther 2004; 309:677-83. [PMID: 14742738 DOI: 10.1124/jpet.103.063008] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Alkyl-substituted butyrolactones have both inhibitory and stimulatory effects on GABA(A) receptors. Lactones with small alkyl substitutions at the alpha-position positively modulate the channel, whereas beta-substituted lactones tend to inhibit the GABA(A) receptor. These compounds mediate inhibition through the picrotoxin site of the receptor. A distinct binding site that mediates the stimulatory actions of lactones is presumed to exist, although no definitive evidence to support this claim exists. In the present study, we used in vivo and in vitro assays to evaluate the effects of the enantiomers of a novel lactone, alpha-benzyl-alpha-methyl-gamma-butyrolactone (alpha-BnMeGBL), on the GABA(A) receptor. R-(-)-alpha-BnMeGBL was 2-fold more potent than the S-(+)-alpha-BnMeGBL in blocking pentylenetetrazol-induced seizures in CF-1 mice. The (+)-enantiomer inhibited binding of t-butylbicyclophosporothionate with a higher affinity than the (-)-enantiomer (IC(50) of 0.68 and 1.1 mM, respectively). Whole cell patch-clamp recordings from recombinant alpha1beta2gamma2 receptors stably expressed in HEK293 cells demonstrated that both compounds stimulated GABA-activated current. The maximal stimulation was approximately 2-fold greater with (+)-alpha-BnMeGBL than that seen with (-)-alpha-BnMeGBL. Both enantiomers of alpha-BnMeGBL directly gated the GABA(A) receptor at mM concentrations, in a nonstereoselective manner. Our data demonstrate the stimulatory actions of alpha-BnMeGBL on GABA(A) receptor function display enantioselectivity and provide strong evidence for the existence of a true "lactone site" on the receptor.
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Affiliation(s)
- Eric B Gonzales
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center at Fort Worth, 76107, USA
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18
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Ghoshal N, Mukherjee PK. 3-D-QSAR of N-substituted 4-amino-3,3-dialkyl-2(3H)-furanone GABA receptor modulators using molecular field analysis and receptor surface modelling study. Bioorg Med Chem Lett 2004; 14:103-9. [PMID: 14684308 DOI: 10.1016/j.bmcl.2003.10.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
We report the theoretical validation of the experimentally observed structure-activity relationships (SAR) of a set of N-substituted 4-amino-3,3-dialkyl-2(3H)-furanone GABA receptor modulators showing positive allosteric modulatory activity of the GABA(A) receptor similar to that shown by Loreclazole. Efforts were made to explain some of the conclusions drawn during this study based on a solitary instance of occurrence of the observation within the dataset. Some of the conclusions selected for study included (i) the enhanced activity for the R enantiomer of a compound, (ii) enhanced activity for a compound with an amide type functionality vis-à-vis an amine type functionality at C-4, (iii) enhanced activity for a compound with a carboxamide or carbamate type functionality linking the end group at C-4 over a compound with only the end group attached, provided the alkyl groups attached at C-3 are identical in both cases. The 3-D-QSAR method of molecular field analysis along with receptor-ligand complex stability studies were found to be the most suitable for explaining these activities. While the first conclusion was comprehensively proven, significant support was obtained in case of the latter two. Further comprehensive study is underway and we hope to report them shortly.
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Affiliation(s)
- Nanda Ghoshal
- Drug Design, Development and Molecular Modelling Division, Indian Institute of Chemical Biology (CSIR), Kolkata, India.
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Bruno-Blanch L, Gálvez J, García-Domenech R. Topological virtual screening: a way to find new anticonvulsant drugs from chemical diversity. Bioorg Med Chem Lett 2003; 13:2749-54. [PMID: 12873507 DOI: 10.1016/s0960-894x(03)00535-3] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A topological virtual screening (tvs) test is presented, which is capable of identifying new drug leaders with anticonvulsant activity. Molecular structures of both anticonvulsant-active and non active compounds, extracted from the Merck Index database, were represented using topological indexes. By means of the application of a linear discriminant analysis to both sets of structures, a topological anticonvulsant model (tam) was obtained, which defines a connectivity function. On the basis of this model, 41 new structures with anticonvulsant activity have been identified by a topological virtual screening.
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Affiliation(s)
- L Bruno-Blanch
- Biological Sciences Department, Faculty of Exact Sciences, National University of La Plata, 47 and 115 Street, B1900AVV La Plata, Argentina
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20
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El Hadri A, Abouabdellah A, Thomet U, Baur R, Furtmüller R, Sigel E, Sieghart W, Dodd RH. N-Substituted 4-amino-3,3-dipropyl-2(3H)-furanones: new positive allosteric modulators of the GABA(A) receptor sharing electrophysiological properties with the anticonvulsant loreclezole. J Med Chem 2002; 45:2824-31. [PMID: 12061884 DOI: 10.1021/jm011082k] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
1,4-Addition of benzylamine to 2(5H)-furanone followed by dialkylation of the 3-position with allylbromide gave (+/-)-4-benzyl-3,3-diallyl-2(3H)-furanone (8), which served as the intermediate for the synthesis of various N-substituted 4-amino-3,3-dipropyl-2(3H)-furanones (+/-)-9a-l. The compounds were evaluated for their capacity to potentiate or inhibit GABA-evoked currents in Xenopus laevis oocytes expressing recombinant alpha1beta2gamma2 GABA(A) receptors. The benzyl, ethyl, and allyl carbamates ((R)-9a (100 microM), (+/-)-9b (100 microM), (+/-)-9c (200 microM)) stimulated GABA currents by 279 +/- 47%, 426 +/- 8%. and 765 +/- 61%, respectively, while the phenylcarboxamide (+/-)-9f (200 microM) stimulated currents by 420 +/- 33%. Concentration-response studies showed that compound 9c was approximately twice as potent in stimulating GABA currents as alpha-EMTBL (2), the most potent 3,3-dialkylbutyrolactone known to date. On the other hand, the N-sulfonyl analogues were much less active or even inhibited GABA-evoked currents. In vitro radioligand displacement studies on rat brain membranes showed that these compounds did not bind to the benzodiazepine or GABA recognition sites of the GABA(A) receptor. However, these compounds generally weakly displaced [(35)S]-TBPS (approximately 50% displacement at 100 microM), though potencies did not correlate with GABA current potentiation. Results obtained with alpha1beta1 and mutant alpha1beta2N265S receptors, which compared to alpha1beta2 receptors are both much less sensitive to current stimulation produced by the anticonvulsant loreclezole, suggest that at least some of these aminobutyrolactones, (e.g., 9a, 9c), and interestingly also alpha-EMTBL, share stimulatory properties with loreclezole.
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Affiliation(s)
- Ahmed El Hadri
- Institut de Chimie des Substances Naturelles, Centre National de la Recherche Scientifique, 91198 Gif-sur-Yvette Cedex, France
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Dibas MI, Dillon GH. The central nervous system convulsant pentylenetetrazole stimulates gamma-aminobutyric acid (GABA)-activated current in picrotoxin-resistant GABA(A) receptors in HEK293 cells. Neurosci Lett 2000; 285:193-6. [PMID: 10806319 DOI: 10.1016/s0304-3940(00)01064-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We tested the ability of the central nervous system convulsant pentylenetetrazole (PTZ) to inhibit gamma-aminobutyric acid (GABA)-gated current in receptors expressing a mutation that rendered them resistant to picrotoxin. Consistent with previous reports, receptors expressing beta2(T246F), along with alpha3 and gamma2 subunits, resulted in a greatly diminished sensitivity to picrotoxin. Sensitivity to PTZ was completely abolished in the mutant receptor, confirming the hypothesis that PTZ acts at the picrotoxin site. Quite unexpected, however, was our finding that PTZ elicited marked stimulation (up to 400% of control) in the mutated receptors. This stimulatory effect was not mediated via an interaction with the benzodiazepine site, as preincubation with the benzodiazepine antagonist flumazenil did not block the PTZ-induced stimulation. Our results reveal the existence of a novel stimulatory domain of PTZ in GABA(A) receptors.
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Affiliation(s)
- M I Dibas
- Department of Pharmacology, University of North Texas Health Science Center at Fort Worth, 3500 Camp Bowie Boulevard, Fort Worth, TX 76107, USA
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22
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Bravo P, Arnone A, Bandiera P, Bruché L, Ohashi Y, Ono T, Sekine A, Zanda M. Stereoselective Synthesis of Enantiomerically Pure β-Fluoroalkyl γ-Butyrolactones by Sulfoxide-Directed Lactonization. European J Org Chem 1999. [DOI: 10.1002/(sici)1099-0690(199901)1999:1<111::aid-ejoc111>3.0.co;2-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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