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Benzomorphan scaffold for opioid analgesics and pharmacological tools development: A comprehensive review. Eur J Med Chem 2018; 148:410-422. [PMID: 29477074 DOI: 10.1016/j.ejmech.2018.02.046] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 02/12/2018] [Accepted: 02/13/2018] [Indexed: 01/21/2023]
Abstract
Benzomorphan, derived by morphine skeleton simplification, has been the subject of exploration in medicinal chemistry for the development of new drugs and pharmacological tools to explore opioid pharmacology in vitro and in vivo. Building upon these evidences, the design and synthesis of benzomorphan-based compounds, appropriately modified at the basic nitrogen and/or the phenolic hydroxyl (8-OH) group, represent a valid and versatile strategy to obtain analgesics. In this review, to improve the body of information in this field, we report structure activity-relationships (SARs) of benzomorphan-based compounds analysing data literature of last 25 years. Collectively, SARs data highlighted that the benzomorphan nucleus represents a template in the achievement of a specific functional profile, by modifying N-substituent or 8-OH group.
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2
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Li Q, Kim SK, Goddard WA, Chen G, Tan H. Predicted structures for kappa opioid G-protein coupled receptor bound to selective agonists. J Chem Inf Model 2015; 55:614-27. [PMID: 25642595 DOI: 10.1021/ci500523z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Human kappa opioid receptor (κ-OR), a G protein-coupled receptor (GPCR), has been identified as a drug target for treatment of such human disorders as pain perception, neuroendocrine physiology, affective behavior, and cognition. In order to find more selective and active agonists, one would like to do structure based drug design. Indeed, there is an X-ray structure for an antagonist bound to κ-OR, but structures for activated GPCRs are quite different from those for the inactive GPCRs. Here we predict the ensemble of 24 low-energy structures of human kappa opioid receptor (κ-OR), obtained by application of the GEnSeMBLE (GPCR Ensemble of Structures in Membrane Bilayer Environment) complete sampling method, which evaluates 13 trillion combinations of tilt and rotation angles for κ-OR to select the best 24. To validate these structures, we used the DarwinDock complete sampling method to predict the binding sites for five known agonists (ethylketocyclazocine, bremazocine, pentazocine, nalorphine, and morphine) bound to all 24 κ-OR conformations. We find that some agonists bind selectively to receptor conformations that lack the salt bridge between transmembrane domains 3 and 6 as expected for active conformations. These 3D structures for κ-OR provide a structural basis for understanding ligand binding and activation of κ-OR, which should be useful for guiding subtype specific drug design.
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Affiliation(s)
- Quanjie Li
- †Materials and Process Simulation Center (MC-139-74), California Institute of Technology, Pasadena, California 91125, United States.,‡College of Chemistry, Beijing Normal University, Beijing, 100875, People's Republic of China
| | - Soo-Kyung Kim
- †Materials and Process Simulation Center (MC-139-74), California Institute of Technology, Pasadena, California 91125, United States
| | - William A Goddard
- †Materials and Process Simulation Center (MC-139-74), California Institute of Technology, Pasadena, California 91125, United States
| | - Guangju Chen
- ‡College of Chemistry, Beijing Normal University, Beijing, 100875, People's Republic of China
| | - Hongwei Tan
- ‡College of Chemistry, Beijing Normal University, Beijing, 100875, People's Republic of China
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3
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Gopishetty B, Zhang S, Kharkar PS, Antonio T, Reith M, Dutta AK. Modification of agonist binding moiety in hybrid derivative 5/7-{[2-(4-aryl-piperazin-1-yl)-ethyl]-propyl-amino}-5,6,7,8-tetrahydro-naphthalen-1-ol/-2-amino versions: impact on functional activity and selectivity for dopamine D2/D3 receptors. Bioorg Med Chem 2013; 21:3164-74. [PMID: 23623679 DOI: 10.1016/j.bmc.2013.03.059] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Revised: 03/07/2013] [Accepted: 03/16/2013] [Indexed: 02/08/2023]
Abstract
The goal of the present study was to explore, in our previously developed hybrid template, the effect of introduction of additional heterocyclic rings (mimicking catechol hydroxyl groups as bioisosteric replacement) on selectivity and affinity for the D3 versus D2 receptor. In addition, we wanted to explore the effect of derivatization of functional groups of the agonist binding moiety in compounds developed by us earlier from the hybrid template. Binding affinity (K(i)) of the new compounds was measured with tritiated spiperone as the radioligand and HEK-293 cells expressing either D2 or D3 receptors. Functional activity of selected compounds was assessed in the GTPγS binding assay. In the imidazole series, compound 10a exhibited the highest D3 affinity whereas the indole derivative 13 exhibited similar high D3 affinity. Functionalization of the amino group in agonist (+)-9d with different sulfonamides derivatives improved the D3 affinity significantly with (+)-14f exhibiting the highest affinity. However, functionalization of the hydroxyl and amino groups of 15 and (+)-9d, known agonist and partial agonist, to sulfonate ester and amide in general modulated the affinity. In both cases loss of agonist potency resulted from such derivatization.
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Affiliation(s)
- Bhaskar Gopishetty
- Wayne State University, Department of Pharmaceutical Sciences, 259 Mack Ave, Detroit, MI 48202, USA
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4
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Wentland MP, Jo S, Gargano JM, VanAlstine MA, Cohen DJ, Bidlack JM. Redefining the structure-activity relationships of 2,6-methano-3-benzazocines. Part 8. High affinity ligands for opioid receptors in the picomolar Ki range: oxygenated N-(2-[1,1'-biphenyl]-4-ylethyl) analogues of 8-CAC. Bioorg Med Chem Lett 2012; 22:7340-4. [PMID: 23142613 DOI: 10.1016/j.bmcl.2012.10.081] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2012] [Revised: 10/13/2012] [Accepted: 10/16/2012] [Indexed: 10/27/2022]
Abstract
N-[2-(4'-methoxy[1,1'-biphenyl]-4-yl)ethyl]-8-CAC (1) is a high affinity (K(i)=0.084 nM) ligand for the μ opioid receptor and served as the lead compound for this study. Analogues of 1 were made in hopes of identifying an SAR within a series of oxygenated (distal) phenyl derivatives. A number of new analogues were made having single-digit pM affinity for the μ receptor. The most potent was the 3',4'-methylenedioxy analogue 18 (K(i)=1.6 pM).
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Affiliation(s)
- Mark P Wentland
- Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
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5
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Fang B, Zheng H, Zhao C, Jing P, Li H, Xie X, She X. Synthesis of the Tetracyclic Core (ABCE Rings) of Daphenylline. J Org Chem 2012; 77:8367-73. [DOI: 10.1021/jo301533f] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Bowen Fang
- State Key Laboratory
of Applied
Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, 730000, PR China
| | - Huaiji Zheng
- State Key Laboratory
of Applied
Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, 730000, PR China
| | - Changgui Zhao
- State Key Laboratory
of Applied
Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, 730000, PR China
| | - Peng Jing
- State Key Laboratory
of Applied
Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, 730000, PR China
| | - Huilin Li
- State Key Laboratory
of Applied
Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, 730000, PR China
| | - Xingang Xie
- State Key Laboratory
of Applied
Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, 730000, PR China
| | - Xuegong She
- State Key Laboratory
of Applied
Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, Gansu, 730000, PR China
- State Key Laboratory for Oxo
Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, Gansu, 730000,
PR China
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6
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Abstract
Twin and triplet drugs are defined as compounds that contain respectively two and three pharmacophore components exerting pharmacological effects in a molecule. The twin drug bearing the same pharmacophores is a "symmetrical twin drug", whereas that possessing different pharmacophores is a "nonsymmetrical twin drug." In general, the symmetrical twin drug is expected to produce more potent and/or selective pharmacological effects, whereas the nonsymmetrical twin drug is anticipated to show both pharmacological activities stemming from the individual pharmacophores (dual action). On the other hand, nonsymmetrical triplet drugs, which have two of the same pharmacophores and one different moiety, are expected to elicit both increased pharmacological action and dual action. The two identical portions could bind the same receptor sites simultaneously while the third portion could bind a different receptor site or enzyme. This review will mainly focus on the twin and triplet drugs with an evaluation of their in vivo pharmacological effects, and will also include a description of their pharmacology and synthesis.
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Affiliation(s)
- Hideaki Fujii
- School of Pharmacy, Kitasato University, 5-9-1, Shirokane, Minato-ku, Tokyo 108-8641, Japan.
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7
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Insights into subtype selectivity of opioid agonists by ligand-based and structure-based methods. J Mol Model 2010; 17:477-93. [DOI: 10.1007/s00894-010-0745-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2010] [Accepted: 05/04/2010] [Indexed: 11/24/2022]
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8
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Wentland MP, Lu Q, Ganorkar R, Zhang SZ, Jo S, Cohen DJ, Bidlack JM. Redefining the structure-activity relationships of 2,6-methano-3-benzazocines. Part 7: syntheses and opioid receptor properties of cyclic variants of cyclazocine. Bioorg Med Chem Lett 2008; 19:365-8. [PMID: 19091564 DOI: 10.1016/j.bmcl.2008.11.076] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2008] [Revised: 11/18/2008] [Accepted: 11/20/2008] [Indexed: 10/21/2022]
Abstract
A series of 7,8- and 8,9-fused triazole and imidazole analogues of cyclazocine have been made and characterized in opioid receptor binding and [(35)S]GTPgammaS assays. Target compounds were designed to explore the SAR surrounding our lead molecule for this study, namely the 8,9-fused pyrrolo analogue 2 of cyclazocine. Compared to 2, many of the new compounds in this study displayed very high affinity for opioid receptors.
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Affiliation(s)
- Mark P Wentland
- Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, 110 8th St., Troy, NY 12180, USA.
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9
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VanAlstine MA, Wentland MP, Cohen DJ, Bidlack JM. Redefining the structure-activity relationships of 2,6-methano-3-benzazocines. 5. Opioid receptor binding properties of N-((4'-phenyl)-phenethyl) analogues of 8-CAC. Bioorg Med Chem Lett 2007; 17:6516-20. [PMID: 17935988 DOI: 10.1016/j.bmcl.2007.09.082] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2007] [Revised: 09/22/2007] [Accepted: 09/25/2007] [Indexed: 11/16/2022]
Abstract
A series of aryl-containing N-monosubstituted analogues of the lead compound 8-[N-((4'-phenyl)-phenethyl)]-carboxamidocyclazocine were synthesized and evaluated to probe a putative hydrophobic binding pocket of opioid receptors. Very high binding affinity to the mu opioid receptor was achieved though the N-(2-(4'-methoxybiphenyl-4-yl)ethyl) analogue of 8-CAC. High binding affinity to mu and very high binding affinity to kappa opioid receptors was observed for the N-(3-bromophenethyl) analogue of 8-CAC. High binding affinity to all three opioid receptors were observed for the N-(2-naphthylethyl) analogue of 8-CAC.
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Affiliation(s)
- Melissa A VanAlstine
- Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
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10
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Wentland MP, VanAlstine M, Kucejko R, Lou R, Cohen DJ, Parkhill AL, Bidlack JM. Redefining the structure-activity relationships of 2,6-methano-3-benzazocines. 4. Opioid receptor binding properties of 8-[N-(4'-phenyl)-phenethyl)carboxamido] analogues of cyclazocine and ethylketocycalzocine. J Med Chem 2006; 49:5635-9. [PMID: 16942039 DOI: 10.1021/jm060278n] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The synthesis and evaluation of a series of aryl-containing N-monosubstituted analogues of the lead compound 8-carboxamidocyclazocine were performed to probe a putative hydrophobic binding pocket of opioid receptors. High binding affinity to mu, kappa, and delta opioid receptors was observed for the 8-[N-(4'-phenyl)-phenethyl)carboxamido] analogue.
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MESH Headings
- Animals
- CHO Cells
- Cricetinae
- Cricetulus
- Cyclazocine/analogs & derivatives
- Cyclazocine/chemical synthesis
- Cyclazocine/pharmacology
- Ethylketocyclazocine/analogs & derivatives
- Ethylketocyclazocine/chemical synthesis
- Ethylketocyclazocine/pharmacology
- Humans
- Hydrophobic and Hydrophilic Interactions
- Radioligand Assay
- Receptors, Opioid, delta/drug effects
- Receptors, Opioid, delta/metabolism
- Receptors, Opioid, kappa/drug effects
- Receptors, Opioid, kappa/metabolism
- Receptors, Opioid, mu/drug effects
- Receptors, Opioid, mu/metabolism
- Stereoisomerism
- Structure-Activity Relationship
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Affiliation(s)
- Mark P Wentland
- Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, New York 12180, USA.
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11
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Kuz’mina NE, Osipova ES, Kuz’min VS, Sitnikov VB. Effect of the tyramine fragment of opioid receptor ligands on their agonist and antagonist properties. Pharm Chem J 2006. [DOI: 10.1007/s11094-006-0104-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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12
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Díaz N, Benvenga M, Emmerson P, Favors R, Mangold M, McKinzie J, Patel N, Peters S, Quimby S, Shannon H, Siegel M, Statnick M, Thomas E, Woodland J, Surface P, Mitch C. SAR and biological evaluation of novel trans-3,4-dimethyl-4-arylpiperidine derivatives as opioid antagonists. Bioorg Med Chem Lett 2005; 15:3844-8. [PMID: 15993591 DOI: 10.1016/j.bmcl.2005.05.123] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2005] [Revised: 05/27/2005] [Accepted: 05/31/2005] [Indexed: 10/25/2022]
Abstract
The phenolic hydroxy group of opiate-derived ligands is of known importance for biological activity. We have developed a SAR study around LY255582 by comparing the effect of the hydroxy group in the 2- and 4-position of the phenyl ring. Also, we have proved that the 3-position of the phenyl ring is optimal for opioid activity. Furthermore, we have successfully replaced the hydroxy group in LY255582 by carbamate and carboxamide groups. The new analogs have high affinity for the opioid receptors comparable to the corresponding phenol. Carboxamide analog 12 has an improved metabolism profile and proved to be efficacious in in vivo studies.
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Affiliation(s)
- Nuria Díaz
- Discovery Research, Eli Lilly and Company, Indianapolis, IN 46285, USA.
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13
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Wentland MP, Sun X, Bu Y, Lou R, Cohen DJ, Bidlack JM. Redefining the structure-activity relationships of 2,6-methano-3-benzazocines. Part 3: 8-Thiocarboxamido and 8-thioformamido derivatives of cyclazocine. Bioorg Med Chem Lett 2005; 15:2547-51. [PMID: 15863314 DOI: 10.1016/j.bmcl.2005.03.056] [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] [Received: 12/30/2004] [Revised: 03/10/2005] [Accepted: 03/15/2005] [Indexed: 11/15/2022]
Abstract
8-Position variants of cyclazocine have been made where the phenolic 8-OH was replaced by thioamide, amidine, guanidine, urea and thiourea groups. High affinity for opioid receptors was observed for the 8-CSNH2 and 8-NHCHS analogues indicating that these groups are isosteric with not only the 8-OH but with the previously synthesized 8-CONH2 and 8-NHCHO cyclazocine derivatives.
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Affiliation(s)
- Mark P Wentland
- Department of Chemistry and Chemical Biology, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
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14
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15
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Le Bourdonnec B, Belanger S, Cassel JA, Stabley GJ, DeHaven RN, Dolle RE. trans -3,4-Dimethyl-4-(3-carboxamidophenyl)piperidines: A novel class of μ-Selective opioid antagonists. Bioorg Med Chem Lett 2003; 13:4459-62. [PMID: 14643346 DOI: 10.1016/j.bmcl.2003.09.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
trans-3,4-Dimethyl-4-(3-carboxamidophenyl)piperidines constitute a novel class of micro opioid receptor antagonists. The CONH(2) group was found to be an effective isostere of the phenolic OH moiety. Structure-activity relationships at the piperidine nitrogen position led to the identification of several ligands displaying high affinity toward the cloned human micro opioid receptors, good selectivity micro/delta, micro/kappa, and potent in vitro antagonist activity.
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Affiliation(s)
- Bertrand Le Bourdonnec
- Department of Chemistry, Adolor Corporation, 700 Pennsylvania Drive, Exton, PA 19341, USA.
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16
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Neumeyer JL, Zhang A, Xiong W, Gu XH, Hilbert JE, Knapp BI, Negus SS, Mello NK, Bidlack JM. Design and Synthesis of Novel Dimeric Morphinan Ligands for κ and μ Opioid Receptors. J Med Chem 2003; 46:5162-70. [PMID: 14613319 DOI: 10.1021/jm030139v] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A novel series of morphinans were synthesized, and their binding affinity at and functional selectivity for micro, delta, and kappa opioid receptors were evaluated. These dimeric ligands can be viewed as dimeric morphinans, which were formed by coupling two identical morphinan pharmacophores (cyclorphan (1) or MCL 101 (2)) with varying connecting spacers. Ligands 6 and 7 with alkyl spacers on the nitrogen position and ligands 8 and 9 in which the two morphinan pharmacophores were coupled by ether moieties at the 3-hydroxyl positions showed significant decrease in affinity at all three opioid receptors. An improvement in the affinity was achieved by introducing an ester moiety as the spacer in the dimeric morphinans. It was observed that the affinity of these ligands was sensitive to the character and length of the spacer. Compound 13 (MCL-139) with a 4-carbon ester spacer, compound 17 (MCL-144) containing a 10-carbon spacer, and compound 19 (MCL-145) with the conformationally constrained fumaryl spacer were the most potent ligands in this series, displaying excellent affinities at micro and kappa receptors (K(i) = 0.09-0.2 nM at micro and K(i) = 0.078-0.049 nM at kappa), which were comparable to the parent compound 2. Ligand 12, a compound containing only one morphinan pharmacophore and a long-chain ester group, had affinity at both micro and kappa receptors almost identical to that of the parent ligand 2. In the [(35)S]GTPgammaS binding assay, ligands 13, 17, and 19 and their parent morphinans 1 and 2 stimulated [(35)S]GTPgammaS binding mediated by the micro and kappa receptors. Compounds 13 and 17 were full kappa agonists and partial micro agonists, while compound 19 was a partial agonist at both micro and kappa receptors. These novel ligands, as well as their interesting pharmacological properties, will serve as the basis for our continuing investigation of the dimeric ligands as potential probes for the pharmacotherapy of cocaine abuse and may also open new avenues for the characterization of opioid receptors.
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Affiliation(s)
- John L Neumeyer
- Alcohol and Drug Abuse Research Center, McLean Hospital, Harvard Medical School, 115 Mill Street, Belmont, Massachusetts 02478, USA.
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17
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Wentland MP, Sun X, Ye Y, Lou R, Bidlack JM. Redefining the structure-activity relationships of 2,6-methano-3-benzazocines. Part 2: 8-formamidocyclazocine analogues. Bioorg Med Chem Lett 2003; 13:1911-4. [PMID: 12749896 DOI: 10.1016/s0960-894x(03)00295-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
High affinity binding for mu and kappa opioid receptors has been observed in analogues of cyclazocine, ethylketocyclazocine and naltrexone where the prototypic (of opiates) phenolic OH group was replaced with a formamide (-NHCHO) group. For the 8-formamide analogue of cyclazocine, binding is highly enantiospecific (eudismic ratios approximately 2000 for mu and kappa) with K(i) values </=1 nM observed for the (2R,6R,11R)-isomer, (-)-4. A preliminary SAR revealed that affinity is very sensitive to substitution on the formamide appendage.
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Affiliation(s)
- Mark P Wentland
- Department of Chemistry, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
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