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Teleb M, Rizk OH, Zhang FX, Fronczek FR, Zamponi GW, Fahmy H. Design, synthesis and pharmacological evaluation of some substituted dihydropyrimidines with L-/T-type calcium channel blocking activities. Bioorg Chem 2019; 83:354-366. [DOI: 10.1016/j.bioorg.2018.10.054] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 10/19/2018] [Accepted: 10/26/2018] [Indexed: 12/24/2022]
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2
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Mahajani NS, Chisholm JD. Promoter free allylation of trichloroacetimidates with allyltributylstannanes under thermal conditions to access the common 1,1'-diarylbutyl pharmacophore. Org Biomol Chem 2018; 16:4008-4012. [PMID: 29766199 DOI: 10.1039/c8ob00687c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
1,1'-Diarylbutyl groups are a common pharmacophore found in many biologically active small molecules. To access these systems under mild conditions, the reaction of diarylmethyl trichloroacetimidates with allyltributylstannanes was explored. Simply heating allyltributylstannane with the trichloroacetimidate resulted in substitution of the imidate with an allyl group. Unlike other methods used to access these systems, no strong base, transition metal catalyst, Brønsted acid or Lewis acid promoter was required to affect the transformation. Conversions are best with electron rich benzylic trichloroacetimidate systems, where excellent yields are achieved just by refluxing the reactants together in nitromethane.
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Affiliation(s)
- Nivedita S Mahajani
- Department of Chemistry, Syracuse University, 1-014 Center for Science and Technology, Syracuse, NY 13244, USA.
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3
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Design and synthesis of new potent N,N -bis(arylalkyl)piperazine derivatives as multidrug resistance (MDR) reversing agents. Eur J Med Chem 2018; 147:7-20. [DOI: 10.1016/j.ejmech.2018.01.092] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Revised: 01/18/2018] [Accepted: 01/28/2018] [Indexed: 01/06/2023]
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4
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Carosati E, Cosimelli B, Ioan P, Severi E, Katneni K, Chiu FCK, Saponara S, Fusi F, Frosini M, Matucci R, Micucci M, Chiarini A, Spinelli D, Budriesi R. Understanding Oxadiazolothiazinone Biological Properties: Negative Inotropic Activity versus Cytochrome P450-Mediated Metabolism. J Med Chem 2016; 59:3340-52. [PMID: 26962886 DOI: 10.1021/acs.jmedchem.6b00030] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present a series of oxadiazolothiazinones, selective inotropic agents on isolated cardiac tissues, devoid of chronotropy and vasorelaxant activity. Functional and binding data for the precursor of the series (compound 1) let us hypothesize LTCC blocking activity and the existence of a recognition site specific for this scaffold. We synthesized and tested 22 new derivatives: introducing a para-methoxyphenyl at C-8 led to compound 12 (EC50 = 0.022 μM), twice as potent as its para-bromo analogue (1). For 10 analogues, we extended the characterization of the biological properties by including the assessment of metabolic stability in human liver microsomes and cytochrome P450 inhibition potential. We observed that the methoxy group led to active compounds with low metabolic stability and high CYP inhibition, whereas the protective effect of bromine resulted in enhanced metabolic stability and reduced CYP inhibition. Thus, we identified two para-bromo benzothiazino-analogues as candidates for further studies.
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Affiliation(s)
- Emanuele Carosati
- Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia , Via Elce di Sotto 10, 06123 Perugia, Italy.,Centre for Drug Candidate Optimisation, Monash Institute of Pharmaceutical Sciences , 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Barbara Cosimelli
- Dipartimento di Farmacia, Università di Napoli "Federico II" , Via D. Montesano 49, 80131 Napoli, Italy
| | - Pierfranco Ioan
- Dipartimento di Farmacia e Biotecnologie, Università di Bologna , Via Belmeloro 6, 40126 Bologna, Italy
| | - Elda Severi
- Dipartimento di Farmacia, Università di Napoli "Federico II" , Via D. Montesano 49, 80131 Napoli, Italy
| | - Kasiram Katneni
- Centre for Drug Candidate Optimisation, Monash Institute of Pharmaceutical Sciences , 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Francis C K Chiu
- Centre for Drug Candidate Optimisation, Monash Institute of Pharmaceutical Sciences , 381 Royal Parade, Parkville, VIC 3052, Australia
| | - Simona Saponara
- Dipartimento di Scienze della Vita, Università degli Studi di Siena , Via A. Moro 2, 53100 Siena, Italy
| | - Fabio Fusi
- Dipartimento di Scienze della Vita, Università degli Studi di Siena , Via A. Moro 2, 53100 Siena, Italy
| | - Maria Frosini
- Dipartimento di Scienze della Vita, Università degli Studi di Siena , Via A. Moro 2, 53100 Siena, Italy
| | - Rosanna Matucci
- Dipartimento di Neuroscienze, Area del Farmaco e Salute del Bambino (NEUROFARBA) , Viale Pieraccini 6, 50139 Firenze, Italy
| | - Matteo Micucci
- Dipartimento di Farmacia e Biotecnologie, Università di Bologna , Via Belmeloro 6, 40126 Bologna, Italy
| | - Alberto Chiarini
- Dipartimento di Farmacia e Biotecnologie, Università di Bologna , Via Belmeloro 6, 40126 Bologna, Italy
| | - Domenico Spinelli
- Dipartimento di Chimica 'G. Ciamician', Alma Mater Studiorum-Università di Bologna , Via Selmi 2, 40126 Bologna, Italy
| | - Roberta Budriesi
- Dipartimento di Farmacia e Biotecnologie, Università di Bologna , Via Belmeloro 6, 40126 Bologna, Italy
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5
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Orlandi F, Coronnello M, Bellucci C, Dei S, Guandalini L, Manetti D, Martelli C, Romanelli MN, Scapecchi S, Salerno M, Menif H, Bello I, Mini E, Teodori E. New structure-activity relationship studies in a series of N,N-bis(cyclohexanol)amine aryl esters as potent reversers of P-glycoprotein-mediated multidrug resistance (MDR). Bioorg Med Chem 2012; 21:456-65. [PMID: 23245571 DOI: 10.1016/j.bmc.2012.11.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Revised: 11/07/2012] [Accepted: 11/12/2012] [Indexed: 10/27/2022]
Abstract
As a continuation of previous research on a new series of potent and efficacious P-gp-dependent multidrug resistant (MDR) reversers with a N,N-bis(cyclohexanol)amine scaffold, we have designed and synthesized several analogs by modulation of the two aromatic moieties linked through ester functions to the N,N-bis(cyclohexanol)amine, aiming to optimize activity and to extend structure-activity relationships (SAR) within the series. This scaffold, when esterified with two different aromatic carboxylic acids, gives origin to four geometric isomers (cis/trans, trans/trans, cis/cis and trans/cis). The new compounds were tested on doxorubicin-resistant erythroleukemia K562 cells (K562/DOX) in the pirarubicin uptake assay. Most of them resulted in being potent modulators of the extrusion pump P-gp, showing potency values ([I](0.5)) in the submicromolar and nanomolar range. Of these, compounds 2b, 2c, 3d, 5a-d and 6d, showed excellent efficacy with a α(max) close to 1. Selected compounds (2d, 3a, 3b, 5a-d) were further studied to evaluate their doxorubicin cytotoxicity potentiation (RF) on doxorubicin-resistant erythroleukemia K562 cells and were found able to enhance significantly doxorubicin cytotoxicity on K562/DOX cells. The results of both pirarubicin uptake and the cytotoxicity assay, indicate that the new compounds of the series are potent P-gp-mediated MDR reversers. They present a structure with a mix of flexible and rigid moieties, a property that seems critical to allow the molecules to choose the most productive of the several binding modes possible in the transporter recognition site. In particular, compounds 5c and 5d, similar to the already reported analogous isomers 1c and 1d,(29) are potent and efficacious modulators of P-gp-dependent MDR and may be promising leads for the development of MDR-reversal drugs.
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Affiliation(s)
- Francesca Orlandi
- Dipartimento di Scienze Farmaceutiche, Università di Firenze, via Ugo Schiff 6, 50019 Sesto Fiorentino, FI, Italy
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6
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Evolving therapeutic indications for N-type calcium channel blockers: from chronic pain to alcohol abuse. Future Med Chem 2011; 2:791-802. [PMID: 21426203 DOI: 10.4155/fmc.10.30] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Clinical exploitation of the therapeutic potential of calcium channels has long been limited to L-type blockers for cardiovascular diseases. Recently, N-type blockers have been fully validated for the treatment of chronic pain, following approval of the intrathecally active ziconotide (Prialt(®)). This review describes the successful efforts to broaden the therapeutic scope of this mechanism to other major CNS indications, based on the discovery of N-type blockers orally active against pain. In animal models, the N-type blocker and pain-reducing NP078585 is efficacious against key elements of ethanol dependency, including self-administration and relapse. NP078585 moderately stimulates brain dopamine release without inducing reward or hyperlocomotion. N-type blockers may emerge as a novel class of 'dopamine stabilizers' for the treatment of drug dependency and other neuropsychiatric disorders without the side effects of current therapies.
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7
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Zhu Q, Lu Y. Chiral primary amine mediated conjugate addition of branched aldehydes to vinyl sulfone: asymmetric generation of quaternary carbon centers. Chem Commun (Camb) 2010; 46:2235-7. [DOI: 10.1039/b919549a] [Citation(s) in RCA: 93] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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8
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Andersson A, Baell JB, Duggan PJ, Graham JE, Lewis RJ, Lumsden NG, Tranberg CE, Tuck KL, Yang A. ω-Conotoxin GVIA mimetics based on an anthranilamide core: Effect of variation in ammonium side chain lengths and incorporation of fluorine. Bioorg Med Chem 2009; 17:6659-70. [DOI: 10.1016/j.bmc.2009.07.063] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2009] [Revised: 07/23/2009] [Accepted: 07/26/2009] [Indexed: 11/24/2022]
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9
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Badorrey R, Portaña E, Díaz-de-Villegas MD, Gálvez JA. Stereocontrolled synthesis of orthogonally protected 2-substituted 4-aminopiperidines. Org Biomol Chem 2009; 7:2912-8. [DOI: 10.1039/b904948g] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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10
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Merkel MJ, Brambrink AM. [Ischemic complications in neurosurgery: use of calcium antagonists]. Anaesthesist 2008; 57:794-802. [PMID: 18551259 DOI: 10.1007/s00101-008-1394-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Dysregulation of the intracellular calcium concentration is thought to play a key role in the so-called ischemic cascade, as well as for the development of cerebral vasospasm after subarachnoid haemorrhaging (SAH). Therefore, the prophylactic/therapeutic administration of cerebral calcium channel blockers for neurosurgical patients appears to be a compelling idea to prevent ischemic complications. There are abundant data on the efficacy of cerebral calcium antagonists in various animal models of central nervous system pathologies, however, very little clinical evidence exists to justify their use in humans in respective situations. So far there is only evidence for a long-term treatment effect of oral nimodipine in patients suffering from SAH, and this is based essentially on one large controlled clinical trial. Experimental results suggest that blockers of other calcium channel subtypes may be promising for future clinical roles in primary or secondary ischemic brain injury. However, it is also possible that calcium-independent mechanisms play a more important role during the development of the ischemic damage than previously assumed. Currently, there is no clinical evidence to support the prophylactic use of calcium antagonists to prevent ischemic complications in neurosurgical patients without SAH.
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Affiliation(s)
- M J Merkel
- Department of Anesthesiology and Peri-Operative Medicine, Oregon Health & Science University, 3181 SW Sam Jackson Park Road, UHS-2, 97239, Portland, OR 97239, USA
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11
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Meng G, Wu N, Zhang C, Su RB, Lu XQ, Liu Y, Yun LH, Zheng JQ, Li J. Analgesic activity of ZC88, a novel N-type voltage-dependent calcium channel blocker, and its modulation of morphine analgesia, tolerance and dependence. Eur J Pharmacol 2008; 586:130-8. [DOI: 10.1016/j.ejphar.2008.02.066] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2007] [Revised: 02/15/2008] [Accepted: 02/20/2008] [Indexed: 10/22/2022]
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12
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Yogeeswari P, Ragavendran JV, Sriram D. Neuropathic pain: strategies in drug discovery and treatment. Expert Opin Drug Discov 2007; 2:169-84. [DOI: 10.1517/17460441.2.2.169] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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13
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Abstract
The voltage-gated calcium channels (VGCCs) are a large and functionally diverse group of ion channels found throughout the central nervous system (CNS) and the periphery. Neuronal functions include the control of neurotransmitter release and neuronal excitability in important pain pathways. In the current review we will give an overview of the data that has been generated in support of these channels performing a pivotal role in the pain pathway.
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Affiliation(s)
- Valentin K Gribkoff
- Knopp Neurosciences, Inc., 100 Technology Drive, Suite 400, Pittsburgh, PA 15219, USA.
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14
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Benjamin ER, Pruthi F, Olanrewaju S, Shan S, Hanway D, Liu X, Cerne R, Lavery D, Valenzano KJ, Woodward RM, Ilyin VI. Pharmacological characterization of recombinant N-type calcium channel (Cav2.2) mediated calcium mobilization using FLIPR. Biochem Pharmacol 2006; 72:770-82. [PMID: 16844100 DOI: 10.1016/j.bcp.2006.06.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2006] [Revised: 06/04/2006] [Accepted: 06/06/2006] [Indexed: 11/24/2022]
Abstract
The N-type voltage-gated calcium channel (Ca(v)2.2) functions in neurons to regulate neurotransmitter release. It comprises a clinically relevant target for chronic pain. We have validated a calcium mobilization approach to assessing Ca(v)2.2 pharmacology in two stable Ca(v)2.2 cell lines: alpha1(B), alpha2delta, beta(3)-HEK-293 and alpha1(B), beta(3)-HEK-293. Ca(v)2.2 channels were opened by addition of KCl and Ca(2+) mobilization was measured by Fluo-4 fluorescence on a fluorescence imaging plate reader (FLIPR(96)). Ca(v)2.2 expression and biophysics were confirmed by patch-clamp electrophysiology (EP). Both cell lines responded to KCl with adequate signal-to-background. Signals from both cell lines were inhibited by omega-conotoxin (ctx)-MVIIa and omega-conotoxin (ctx)-GVIa with IC(50) values of 1.8 and 1nM, respectively, for the three-subunit stable, and 0.9 and 0.6nM, respectively, for the two-subunit stable. Other known Ca(v)2.2 blockers were characterized including cadmium, flunarizine, fluspirilene, and mibefradil. IC(50) values correlated with literature EP-derived values. Novel Ca(v)2.2 pharmacology was identified in classes of compounds with other primary pharmacological activities, including Na(+) channel inhibitors and antidepressants. Novel Na(+) channel compounds with high potency at Ca(v)2.2 were identified in the phenoxyphenyl pyridine, phenoxyphenyl pyrazole, and other classes. The highest potency at Ca(v)2.2 tricyclic antidepressant identified was desipramine.
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Affiliation(s)
- Elfrida R Benjamin
- Purdue Pharma Discovery Research, 6 Cedarbrook Drive, Cranbury, NJ 08512, USA.
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15
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Yamamoto T, Niwa S, Iwayama S, Koganei H, Fujita SI, Takeda T, Kito M, Ono Y, Saitou Y, Takahara A, Iwata S, Yamamoto H, Shoji M. Discovery, structure–activity relationship study, and oral analgesic efficacy of cyproheptadine derivatives possessing N-type calcium channel inhibitory activity. Bioorg Med Chem 2006; 14:5333-9. [PMID: 16616501 DOI: 10.1016/j.bmc.2006.03.040] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2006] [Revised: 03/21/2006] [Accepted: 03/22/2006] [Indexed: 11/29/2022]
Abstract
Antiallergic drug cyproheptadine (Cyp) is known to have inhibitory activities for L-type calcium channels in addition to histamine and serotonin receptors. Since we found that Cyp had an inhibitory activity against N-type calcium channel, Cyp was optimized to obtain more selective N-type calcium channel blocker with analgesic action. As a consequence of the optimization, we found 13 with potent N-type calcium channel inhibitory activity which had lower inhibitory activities against L-type calcium channel, histamine (H1), and serotonin (5-HT2A) receptors than those of Cyp. 13 showed an oral analgesic activity in rat formalin-induced pain model.
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Affiliation(s)
- Takashi Yamamoto
- Pharmaceutical Research Laboratory, Ajinomoto company Inc., 1-1, Suzuki-cho, Kawasaki-ku, Kawasaki-shi, Japan
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16
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Weiss N, De Waard M. [Voltage-dependent calcium channels at the heart of pain perception]. Med Sci (Paris) 2006; 22:396-404. [PMID: 16597409 DOI: 10.1051/medsci/2006224396] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Voltage-dependent calcium channels represent a major pathway of calcium entry into neurons, where they participate actively to cell excitability and to the molecular processes of synaptic transmission. For that reason, they have been the direct or indirect pharmacological targets of analgesics and this long before their implication in the physiology of nociception had been demonstrated. These last years, the still more refined molecular characterization of these channels and their associated regulatory subunits and the demonstration of their implication in nociceptive processes indicates that these structures are prime pharmacological targets for the management of pain. Herein, we detail the recent breakthroughs on calcium channel structure, function and pharmacology, review the implication of calcium channels in the transmission of nociception, and evaluate their importance as targets for the treatment of pain perception. The search for specific inhibitors of voltage-dependent calcium channels appears as a prelude to the development of new promising analgesic molecules.
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Affiliation(s)
- Norbert Weiss
- Laboratoire Canaux Calciques, Fonctions et Pathologies, Inserm U607, DRDC, Bâtiment C3, 17, rue des Martyrs, 38054 Grenoble Cedex 09, France
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Teodori E, Dei S, Garnier-Suillerot A, Gualtieri F, Manetti D, Martelli C, Romanelli MN, Scapecchi S, Sudwan P, Salerno M. Exploratory Chemistry toward the Identification of a New Class of Multidrug Resistance Reverters Inspired by Pervilleine and Verapamil Models. J Med Chem 2005; 48:7426-36. [PMID: 16279802 DOI: 10.1021/jm050542x] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
On the basis of the present knowledge of the substrate recognition site of ABC transporter proteins and inspired by the structures of verapamil and pervilleine A, a new class of Pgp-mediated multidrug resistance (MDR) reverters has been designed and synthesized. The new compounds are flexible molecules carrying one or two basic nitrogen atoms flanked, at properly modulated distance, by two aromatic moieties. Most of the molecules studied possess MDR inhibitory activity on anthracycline-resistant erythroleukemia K 562 cells, showing a potency that is higher than that of the reference compound verapamil and, in a few cases (7, 12, 13,17, 20, 22, 28), is in the high nanomolar range. These compounds may be useful leads to develop new MDR reverting agents. In fact, the chemical structure of the class is fairly simple and can be implemented in a variety of ways that will allow the synthesis of new compounds that might be useful leads for the development of drugs to control Pgp-dependent MDR.
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Affiliation(s)
- Elisabetta Teodori
- Dipartimento di Scienze Farmaceutiche, Università di Firenze, via U. Schiff 6, 50019 Sesto Fiorentino (FI), Italy.
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18
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Winquist RJ, Pan JQ, Gribkoff VK. Use-dependent blockade of Cav2.2 voltage-gated calcium channels for neuropathic pain. Biochem Pharmacol 2005; 70:489-99. [PMID: 15950195 DOI: 10.1016/j.bcp.2005.04.035] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2005] [Revised: 04/11/2005] [Accepted: 04/11/2005] [Indexed: 11/28/2022]
Abstract
The translocation of extracellular calcium (Ca(2+)) via voltage-gated Ca(2+) channels (VGCCs) in neurons is involved in triggering multiple physiological cell functions but also the abnormal, pathophysiological responses that develop as a consequence of injury. In conditions of neuropathic pain, VGCCs are involved in supplying the signal Ca(2+) important for the sustained neuronal firing and neurotransmitter release characteristic of these syndromes. Preclinical data have identified N-type VGCCs (Ca(v)2.2) as key participants in contributing to these Ca(2+) signaling events and clinical data with the peptide blocker Prialt have now validated Ca(v)2.2 as a bona fide target for future drug discovery efforts to identify new and novel therapeutics for neuropathic pain. Imperative for the success of such an endeavor will be the ability to identify compounds selective for Ca(v)2.2, versus other VGCCs, but also compounds which demonstrate effective blockade during the pathophysiological states of neuropathic pain without compromising channel activity associated with sustaining normal housekeeping cellular functions. An approach to obtain this research target profile is to identify compounds, which are more potent in blocking Ca(v)2.2 during higher frequencies of firing as compared to the slower more physiologically-relevant frequencies. This may be achieved by identifying compounds with enhanced potency for the inactivated state of Ca(v)2.2. This commentary explores the rationale and options for engineering a use-dependent blocker of Ca(v)2.2. It is anticipated that this use-dependent profile of channel blockade will result in new chemical entities with an improved therapeutic ratio for neuropathic pain.
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Affiliation(s)
- Raymond J Winquist
- Department of Pharmacology, Scion Pharmaceuticals Inc., 200 Boston Avenue, Suite 3600, Medford, MA 02155, USA.
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Gribkoff VK, Winquist RJ. Voltage-gated cation channel modulators for the treatment of stroke. Expert Opin Investig Drugs 2005; 14:579-92. [PMID: 15926865 DOI: 10.1517/13543784.14.5.579] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Neuronal voltage-gated cation channels regulate the transmembrane flux of calcium, sodium and potassium. Neuronal ischaemia occurring during acute ischaemic stroke results in the breakdown in the normal function of these ion channels, contributing to a series of pathological events leading to cell death. A dramatic increase in the intracellular concentration of calcium during neuronal ischaemia plays a particularly important role in the neurotoxic cascade resulting in stroke-related acute neurodegeneration. One approach to provide therapeutic benefit following ischaemic stroke has been to target neuronal voltage-gated cation channels, and particularly blockers of calcium and sodium channels, for post-stroke neuroprotection. A recent development has been the identification of openers of large-conductance calcium- and voltage-dependent potassium channels (maxi-K channels), which hyperpolarize ischaemic neurons, reduce excitatory amino acid release, and reduce ischaemic calcium entry. Thus far, targeting these voltage-gated cation channels has not yet yielded significant clinical benefit. The reasons for this may involve the lack of small-molecule blockers of many neuronal members of these ion channel families and the design of preclinical stroke models, which do not adequately emulate the clinical condition and hence lack sufficient rigor to predict efficacy in human stroke. Furthermore, there may be a need for changes in clinical trial designs to optimise the selection of patients and the course of drug treatment to protect neurons during all periods of potential neuronal sensitivity to neuro-protectants. Clinical trials may also have to be powered to detect small effect sizes or be focused on patients more likely to respond to a particular therapy. The development of future solutions to these problems should result in an improved probability of success for the treatment of stroke.
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Affiliation(s)
- Valentin K Gribkoff
- Department of Biology, Scion Pharmaceuticals, Inc., 200 Boston Avenue, Suite 3600, Medford, MA 02155, USA.
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