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Turnaturi R, Pasquinucci L, Chiechio S, Grasso M, Marrazzo A, Amata E, Dichiara M, Prezzavento O, Parenti C. Exploiting the Power of Stereochemistry in Drug Action: 3-[(2 S,6 S,11 S)-8-Hydroxy-6,11-dimethyl-1,4,5,6-tetrahydro-2,6-methano-3-benzazocin-3(2 H)-yl]- N-phenylpropanamide as Potent Sigma-1 Receptor Antagonist. ACS Chem Neurosci 2020; 11:999-1005. [PMID: 32186844 DOI: 10.1021/acschemneuro.9b00688] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
(+)-(2S,6S,11S)- and (-)-(2R,6R,11R)-Benzomorphan derivatives have a different binding affinity for sigma-1 (σ1R) and opioid receptors, respectively. In this study, we describe the synthesis of the (+)-enantiomer [(+)-LP1] of the benzomorphan MOR agonist/DOR antagonist LP1 [(-)-LP1]. The binding affinity of both (+)-LP1 and (-)-LP1 for σ1R and sigma-2 receptor (σ2R) was tested. Moreover, (+)-LP1 opioid receptor binding affinity was also investigated. Finally, (+)-LP1 was tested in a mouse model of inflammatory pain. Our results showed a nanomolar σ1R and binding affinity for (+)-LP1. Both (+)-LP1 and (-)-LP1 elicited a significant analgesic effect in a formalin test. Differently from (-)-LP1, the analgesic effect of (+)-LP1 was not reversed by naloxone, suggesting a σ1R antagonist profile. Furthermore, σ1R agonist PRE-084 was able to unmask the σ1R antagonistic component of the benzomorphan compound. (+)-LP1 could constitute an useful lead compound to develop new analgesics based on mechanisms of action alternative to opioid receptor activation.
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MESH Headings
- Analgesics/chemistry
- Analgesics/pharmacology
- Analgesics, Opioid/pharmacology
- Animals
- Benzomorphans/chemical synthesis
- Benzomorphans/pharmacology
- Disease Models, Animal
- Mice
- Pain/drug therapy
- Receptors, Opioid/drug effects
- Receptors, Opioid/metabolism
- Receptors, Opioid, delta/drug effects
- Receptors, Opioid, delta/metabolism
- Receptors, Opioid, mu/drug effects
- Receptors, Opioid, mu/metabolism
- Receptors, sigma/antagonists & inhibitors
- Structure-Activity Relationship
- Sigma-1 Receptor
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Affiliation(s)
- Rita Turnaturi
- Department of Drug Sciences, Medicinal Chemistry Section, University of Catania, Viale A. Doria 6, 95125 Catania, Italy
| | - Lorella Pasquinucci
- Department of Drug Sciences, Medicinal Chemistry Section, University of Catania, Viale A. Doria 6, 95125 Catania, Italy
| | - Santina Chiechio
- Department of Drug Sciences, Pharmacology and Toxicology Section, University of Catania, Viale A. Doria 6, 95125 Catania, Italy
- Oasi Research Institute-IRCCS, Troina 94018, Italy
| | - Margherita Grasso
- Department of Drug Sciences, Pharmacology and Toxicology Section, University of Catania, Viale A. Doria 6, 95125 Catania, Italy
- Oasi Research Institute-IRCCS, Troina 94018, Italy
| | - Agostino Marrazzo
- Department of Drug Sciences, Medicinal Chemistry Section, University of Catania, Viale A. Doria 6, 95125 Catania, Italy
| | - Emanuele Amata
- Department of Drug Sciences, Medicinal Chemistry Section, University of Catania, Viale A. Doria 6, 95125 Catania, Italy
| | - Maria Dichiara
- Department of Drug Sciences, Medicinal Chemistry Section, University of Catania, Viale A. Doria 6, 95125 Catania, Italy
| | - Orazio Prezzavento
- Department of Drug Sciences, Medicinal Chemistry Section, University of Catania, Viale A. Doria 6, 95125 Catania, Italy
| | - Carmela Parenti
- Department of Drug Sciences, Pharmacology and Toxicology Section, University of Catania, Viale A. Doria 6, 95125 Catania, Italy
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2
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Turnaturi R, Montenegro L, Marrazzo A, Parenti R, Pasquinucci L, Parenti C. Benzomorphan skeleton, a versatile scaffold for different targets: A comprehensive review. Eur J Med Chem 2018; 155:492-502. [PMID: 29908442 DOI: 10.1016/j.ejmech.2018.06.017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 03/23/2018] [Accepted: 06/06/2018] [Indexed: 12/21/2022]
Abstract
Despite the fact that the benzomorphan skeleton has mainly been employed in medicinal chemistry for the development of opioid analgesics, it is a versatile structure. Its stereochemistry, as well as opportune modifications at the phenolic hydroxyl group and at the basic nitrogen, play a pivotal role addressing the benzomorphan-based compounds to a specific target. In this review, we describe the structure activity-relationships (SARs) of benzomorphan-based compounds acting at sigma 1 receptor (σ1R), sigma 2 receptor (σ2R), voltage-dependent sodium channel, N-Methyl-d-Aspartate (NMDA) receptor-channel complex and other targets. Collectively, the SARs data have highlighted that the benzomorphan nucleus could be regarded as a useful template for the synthesis of drug candidates for different targets.
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Affiliation(s)
- Rita Turnaturi
- Department of Drug Sciences, Medicinal Chemistry Section, University of Catania, Viale A. Doria, 6, 95100, Catania, Italy.
| | - Lucia Montenegro
- Department of Drug Sciences, Pharmaceutical Technology Section, University of Catania, Viale A. Doria 6, 95125, Catania, Italy
| | - Agostino Marrazzo
- Department of Drug Sciences, Medicinal Chemistry Section, University of Catania, Viale A. Doria, 6, 95100, Catania, Italy
| | - Rosalba Parenti
- Department of Biomedical and Biotechnological Sciences, Physiology Section, University of Catania, Catania, Italy
| | - Lorella Pasquinucci
- Department of Drug Sciences, Medicinal Chemistry Section, University of Catania, Viale A. Doria, 6, 95100, Catania, Italy
| | - Carmela Parenti
- Department of Drug Sciences, Pharmacology Section, University of Catania, Viale A. Doria, 6, 95100, Catania, Italy
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3
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Sahn JJ, Hodges TR, Chan JZ, Martin SF. Norbenzomorphan Framework as a Novel Scaffold for Generating Sigma 2 Receptor/PGRMC1 Subtype-Selective Ligands. ChemMedChem 2016; 11:556-61. [PMID: 26915462 PMCID: PMC4811364 DOI: 10.1002/cmdc.201500551] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 01/12/2016] [Indexed: 12/20/2022]
Abstract
A novel structural class with high affinity and subtype selectivity for the sigma 2 receptor has been discovered. Preliminary structure-affinity relationship data are presented showing that 8-substituted 1,3,4,5-tetrahydro-1,5-methanobenzazepine (norbenzomorphan) derivatives elicit modest to high selectivity for the sigma 2 over the sigma 1 receptor subtype. Indeed, piperazine analogue 8-(4-(3-ethoxy-3-oxopropyl)piperazin-1-yl)-1,3,4,5-tetrahydro-1,5-methanobenzazepine-2-carboxylate (SAS-1121) is 574-fold selective for the sigma 2 over the sigma 1 receptor, thereby establishing it as one of the more subtype-selective sigma 2 binding ligands reported to date. Emerging evidence has implicated the sigma 2 receptor in multiple health disorders, so the drug-like characteristics of many of the selective sigma 2 receptor ligands disclosed herein, coupled with their structural similarity to frameworks found in known drugs, suggest that norbenzomorphan analogues may be promising candidates for further development into drug leads.
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Affiliation(s)
- James J Sahn
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street, Stop A5300, Austin, TX, 78712, USA
| | - Timothy R Hodges
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street, Stop A5300, Austin, TX, 78712, USA
| | - Jessica Z Chan
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street, Stop A5300, Austin, TX, 78712, USA
| | - Stephen F Martin
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street, Stop A5300, Austin, TX, 78712, USA.
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4
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Klegraf E, Knauer S, Kunz H. Stereoselective Synthesis of Benzomorphan Derivatives with Perpivaloylated Galactose as the Chiral Auxiliary. Angew Chem Int Ed Engl 2006; 45:2623-6. [PMID: 16548042 DOI: 10.1002/anie.200504090] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Ellen Klegraf
- Institut für Organische Chemie, Johannes Gutenberg-Universität Mainz, 55128 Mainz, Germany
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5
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Abstract
A series of aminothiazole-derived morphinans, benzomorphans, and morphine were synthesized. Although their affinities were somewhat lower than their phenol prototypes, one compound (9a, ATPM) has been identified possessing high affinity and selectivity at the kappa receptor. Functional assays showed that 9a was a full kappa but partial mu agonist; the efficacy at kappa was significantly greater than at mu receptors. This novel compound may be valuable for the development of long-acting analgesics and drug abuse medication.
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Affiliation(s)
- Ao Zhang
- Alcohol and Drug Abuse Research Center, McLean Hospital, Harvard Medical School, 115 Mill Street, Belmont, MA 02478, USA
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6
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Abstract
In order to provide ready access to multigram quantities of the optically pure bremazocines [(-)- and (+)-9,9-dimethyl-5-ethyl-2-hydroxy-2-(1-hydroxy-cyclopropylmethyl)-6,7-benzomorphan)], we have developed an improved non-chromatographic synthesis, and determined the optical purity of their N-nor precursors using a rapid and relatively simple 1H NMR method based on diastereomeric derivatization with optically pure 1-phenylethylisocyanate. This method of determining optical purity should be readily amenable to similar systems containing phenolic amino functionalities. Finally, a greatly simplified methodology for introduction of the N-(1-hydroxycyclopropylmethyl) substituent in bremazocine is described. The improved synthetic method-the overall yield was increased about 3-fold-combined with the practical methodology to determine optical purity will considerably facilitate the employment of these enantiomers as pharmacological tools for examination of the kappa-opioid receptor system, as well as their evaluation as drug abuse treatment agents. This synthesis will also enable the study of these enantiomers for other, non-classical applications (e.g., treatment agents for HIV).
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Affiliation(s)
- Elisabeth Greiner
- Laboratory of Medicinal Chemistry, Building 8, Room B1-23, National Institutes of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Department of Health and Human Services, 8 Center Drive, MSC 0815, Bethesda, MD 20892-0815, USA
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7
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Zhou Q, Duan WH, Cohen DJ, Bidlack JM, Wentland MP. Synthesis and pharmacology of 8-amino-3-[(tetrahydro-2-furanyl)methyl] benzomorphan. Yao Xue Xue Bao 2003; 38:748-53. [PMID: 14730897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
AIM To design and synthesize new chiral 8-(substituted) amino-analogues of 3-[(tetrahydro-2-furanyl)methyl] benzomorphans, to expand knowledge of the structure-activity relationship (SAR) for 8-aminobenzomorphan. METHODS Target compounds were synthesized from the 8-triflate of the optically active 3-[(tetrahydro-2-furanyl)methyl]-2,6-methano-benzomorphans using Pd-catalyzed aminations. Opioid receptor binding experiments were performed to evaluate their biological activities. RESULTS Both 8-amino and 8-phenylamino analogues showed lower binding affinity for mu, delta and kappa receptors than corresponding 8-hydroxy-3-[(tetrahydro-2-furanyl)methyl]-2,6-methano-benzomorphan in vitro. CONCLUSION The relative poor binding affinity of the target compounds did not warrant conducting the in vivo studies to determine if they have the profile(kappa agonist/mu antagonist) that will be potentially useful in the treatment of drug addiction. Further study is in progress.
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Affiliation(s)
- Qun Zhou
- Department of Chemistry, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
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8
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Abstract
We describe a highly efficient, general strategy for the enantioselective synthesis of benzomorphans (45-46% overall yield from commercially available material). The new synthesis demonstrates the effectiveness of an unprecedented diastereoselective cycloisomerization via migratory hydroamination and the power of palladium-catalyzed asymmetric allylic alkylation (AAA) of simple ketone enolates in the context of complex synthesis. The strategy outlined here for the enantioselective synthesis of three contiguous stereogenic centers and the novel cycloisomerization should have many applications in alkaloid synthesis.
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Affiliation(s)
- Barry M Trost
- Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA.
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9
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Grauert M, Bechtel WD, Weiser T, Stransky W, Nar H, Carter AJ. Synthesis and structure-activity relationships of 6,7-benzomorphan derivatives as use-dependent sodium channel blockers for the treatment of stroke. J Med Chem 2002; 45:3755-64. [PMID: 12166948 DOI: 10.1021/jm020875j] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have synthesized a series of 6,7-benzomorphan derivatives and determined their ability to bind to voltage-dependent sodium channels. We have also compared the functional consequences of this blockade in vitro and in vivo. The ability of the compounds to displace [(3)H]batrachotoxin from voltage-dependent sodium channels was compared with their ability to inhibit [(3)H]glutamate release in rat brain slices and block convulsions in the maximal electroshock test in mice. We found that the hydroxyl function in the 4'-position is crucial for improving the sodium channel blocking properties. Moreover, the stereochemistry and the topology of the N-linked side chain also influence this interaction. Indeed, the affinity is improved by an aromatic substitution in the side chain. By modifying the N substituent and the substitution pattern of the hydroxyl function, we were able to discover (2R)-[2alpha,3(S),6alpha]-1,2,3,4,5,6-hexahydro-6,11,11-tri-methyl-3-[2-(phenylmethoxy)propyl]-2,6-methano-3-benzazocin-10-ol hydrochloride. This compound was chosen as the best candidate for further pharmacological investigations.
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Affiliation(s)
- Matthias Grauert
- Department of Medicinal Chemistry, Boehringer Ingelheim Pharma KG, 88397 Biberach an der Riss, and Corporate Development, Boehringer Ingelheim GmbH, 55216 Ingelheim am Rhein, Germany.
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10
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Kokic M, Honer M, Kessler LJ, Grauert M, Schubiger PA, Ametamey SM. Synthesis and in vitro and in vivo evaluation of [11C]methyl-BIII277CL for imaging the PCP-binding site of the NMDA receptor by pet. J Recept Signal Transduct Res 2002; 22:123-39. [PMID: 12503611 DOI: 10.1081/rrs-120014591] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
A new benzomorphane derivative, [11C]methyl-BIII277CL, was evaluated as a potential radiotracer for visualizing the PCP-binding site of the N-methyl-D-aspartate (NMDA) receptor by positron emission tomography (PET). Methyl-BIII277CL was prepared by reacting the desmethyl compound (BIII277CL) with dimethylsulfate. The pharmacological profile of methyl-BIII277CL was determined by in vitro receptor-screening assays. At a concentration of 100 nM, methyl-BIII277CL showed a significant interaction with the PCP-binding site of the NMDA receptor (79% inhibition of specific binding) and the sigma-binding site (46% inhibition). In displacement assays using mice cortical membranes, methyl-BIII277CL displayed a high affinity at the PCP-binding site of the NMDA receptor (Ki = 49 +/- 14 nmol/L) and a 130-fold lower interaction with the sigma1-binding site (Ki = 6.35 +/- 0.26 micromol/L). For saturation experiments and in vivo studies, methyl-BIII277CL was radiolabeled with 11C at the O-position of the desmethyl precursor (BIII277CL) using [11C]methyliodide with a specific activity of 35-70 GBq/micromol at the end of synthesis (EOS). In saturation assays using rat whole brain membranes [11C]methyl-BIII277CL showed a Kd of 6 +/- 1 nmol/L and a Bmax of 670 +/- 154 fmol/mg protein. Biodistribution and PET studies in rats and pigs, however, indicated a lack of specific binding and unfavorable pharmacokinetics. Kinetic modeling using the 1-tissue compartment model demonstrated for [11C]methyl-BIII277CL a low distribution volume (Dv = 0.98 mL/mL(tissue)) and very high values for the kinetic parameters K1 and k2 (K1 = 0.36 mL/mL(tissue)/min and k2 = 0.37min(-1)) in pig cortex. [11C]methyl-BIII277CL, due to the lack of specificity in vivo, may not be a candidate for imaging the PCP-binding site of the NMDA receptor.
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Affiliation(s)
- Marko Kokic
- Center for Radiopharmaceutical Science of the ETH, Paul Scherrer Institute and Division of Nuclear Medicine, University Hospital Zurich, CH-5232 Villigen PSI, Switzerland
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11
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May EL, Jacobson AE, Mattson MV, Traynor JR, Woods JH, Harris LS, Bowman ER, Aceto MD. Synthesis and in vitro and in vivo activity of (-)-(1R,5R,9R)- and (+)-(1S,5S,9S)-N-alkenyl-, -N-alkynyl-, and -N-cyanoalkyl-5, 9-dimethyl-2'-hydroxy-6,7-benzomorphan homologues. J Med Chem 2000; 43:5030-6. [PMID: 11150174 DOI: 10.1021/jm000317+] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Two of the synthesized (-)-(1R,5R,9R)-N-homologues (N-but-3-enyl- and N-but-3-ynyl-5,9-dimethyl-2'-hydroxy-6,7-benzomorphan (9, 13)) were found to be about 20 times more potent than morphine in the mouse tail-flick assay (ED(50) = 0.05 mg/kg), and (-)-(1R,5R, 9R)-N-but-2-ynyl-5,9-dimethyl-2'-hydroxy-6,7-benzomorphan ((-)-(1R, 5R,9R)-N-but-2-ynylnormetazocine, 12) was about as potent as the opioid antagonist N-allylnormetazocine (AD(50) in the tail-flick vs morphine assay = 0.3 mg/kg). All of the homologues examined had higher affinity for the kappa-opioid receptor than the mu-receptor except (-)-N-but-2-ynyl-normetazocine (12), which had a kappa/mu ratio = 7.8 and a delta/mu ratio = 118. The (-)-N-2-cyanoethyl (3), -allyl (8), and -but-3-ynyl (13) analogues had good affinity (<10 nM) for delta-opioid receptors. Two homologues in the (+)-(1S,5S,9S)-normetazocine series, N-pent-4-enyl (24) and N-hex-5-enyl (25), were high-affinity and selective sigma(1)-ligands (K(i) = 2 nM, sigma(2)/sigma(1) = 1250, and 1 nM, sigma(2)/sigma(1) = 750, respectively); in contrast, N-allylnormetazocine (22) had relatively poor affinity at sigma(1), and its sigma(1)/sigma(2) ratio was <100.
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MESH Headings
- Analgesics/chemical synthesis
- Analgesics/chemistry
- Analgesics/metabolism
- Analgesics/pharmacology
- Animals
- Benzomorphans/chemical synthesis
- Benzomorphans/chemistry
- Benzomorphans/metabolism
- Benzomorphans/pharmacology
- Binding, Competitive
- Cerebral Cortex/metabolism
- Ligands
- Macaca mulatta
- Mice
- Morphine/pharmacology
- Morphine Dependence
- Narcotic Antagonists/chemical synthesis
- Narcotic Antagonists/chemistry
- Narcotic Antagonists/metabolism
- Narcotic Antagonists/pharmacology
- Pain Measurement
- Radioligand Assay
- Receptors, Opioid, delta/agonists
- Receptors, Opioid, delta/metabolism
- Receptors, Opioid, kappa/agonists
- Receptors, Opioid, kappa/metabolism
- Receptors, Opioid, mu/agonists
- Receptors, Opioid, mu/metabolism
- Stereoisomerism
- Structure-Activity Relationship
- Substance Withdrawal Syndrome/drug therapy
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Affiliation(s)
- E L May
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, Virginia 23298-0613, USA
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12
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Neumeyer JL, Bidlack JM, Zong R, Bakthavachalam V, Gao P, Cohen DJ, Negus SS, Mello NK. Synthesis and opioid receptor affinity of morphinan and benzomorphan derivatives: mixed kappa agonists and mu agonists/antagonists as potential pharmacotherapeutics for cocaine dependence. J Med Chem 2000; 43:114-22. [PMID: 10633042 DOI: 10.1021/jm9903343] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
This report concerns the synthesis and preliminary pharmacological evaluation of a novel series of kappa agonists related to the morphinan (-)-cyclorphan (3a) and the benzomorphan (-)-cyclazocine (2) as potential agents for the pharmacotherapy of cocaine abuse. Recent evidence suggests that agonists acting at kappa opioid receptors may modulate the activity of dopaminergic neurons and alter the neurochemical and behavioral effects of cocaine. We describe the synthesis and chemical characterization of a series of morphinans 3a-c, structural analogues of cyclorphan [(-)-3-hydroxy-N-cyclopropylmethylmorphinan S(+)-mandelate, 3a], the 10-ketomorphinans 4a,b, and the 8-ketobenzomorphan 1b. Binding experiments demonstrated that the cyclobutyl analogue 3b [(-)-3-hydroxy-N-cyclobutylmethylmorphinan S(+)-mandelate, 3b, MCL-101] of cyclorphan (3a) had a high affinity for mu, delta, and kappa opioid receptors in guinea pig brain membranes. Both 3a,b were approximately 2-fold more selective for the kappa receptor than for the mu receptor. However 3b (the cyclobutyl analogue) was 18-fold more selective for the kappa receptor in comparison to the delta receptor, while cyclorphan (3a) had only 4-fold greater affinity for the kappa receptor in comparison to the delta receptor. These findings were confirmed in the antinociceptive tests (tail-flick and acetic acid writhing) in mice, which demonstrated that cyclorphan (3a) produced antinociception that was mediated by the delta receptor while 3b did not produce agonist or antagonist effects at the delta receptor. Both 3a,b had comparable kappa agonist properties. 3a,b had opposing effects at the mu receptor: 3b was a mu agonist whereas 3a was a mu antagonist.
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MESH Headings
- Acetic Acid
- Animals
- Benzomorphans/chemical synthesis
- Benzomorphans/metabolism
- Benzomorphans/pharmacology
- Brain/metabolism
- Dose-Response Relationship, Drug
- Ethylketocyclazocine/analogs & derivatives
- Ethylketocyclazocine/pharmacology
- Guinea Pigs
- In Vitro Techniques
- Injections, Intraventricular
- Male
- Mice
- Mice, Inbred ICR
- Morphinans/chemical synthesis
- Morphinans/metabolism
- Morphinans/pharmacology
- Morphine/antagonists & inhibitors
- Narcotic Antagonists/chemical synthesis
- Narcotic Antagonists/pharmacology
- Pain/chemically induced
- Pain/drug therapy
- Pain Measurement
- Reaction Time/drug effects
- Receptors, Opioid, kappa/agonists
- Receptors, Opioid, kappa/antagonists & inhibitors
- Receptors, Opioid, kappa/drug effects
- Receptors, Opioid, kappa/metabolism
- Receptors, Opioid, mu/agonists
- Receptors, Opioid, mu/antagonists & inhibitors
- Receptors, Opioid, mu/drug effects
- Receptors, Opioid, mu/metabolism
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Affiliation(s)
- J L Neumeyer
- Department of Psychiatry, Harvard Medical School, McLean Hospital, Alcohol and Drug Abuse Research Center, Belmont, Massachusetts 02478-9106, USA.
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13
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Wünsch B, Bauschke G, Diekmann H, Höfner G. Stereoselective synthesis and receptor binding of conformationally restricted and flexible 2,4-disubstituted 1,3-dioxanes derived from benzomorphans. Arch Pharm (Weinheim) 1999; 332:413-21. [PMID: 10634091 DOI: 10.1002/(sici)1521-4184(199912)332:12<413::aid-ardp413>3.0.co;2-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The key steps in the stereoselective synthesis of the tricyclic aminomethyl derivatives 19 and 20 and the aminoethyl substituted 1,3-dioxanes 24 and 25 are nucleophilic addition of aryllithium intermediates to the nitroalkene 13, intramolecular transacetalization of the addition products 15 and 16 (only for the tricyclic derivatives 19 and 20) and subsequent reduction of the nitro group. The affinities of the secondary and tertiary amines 19c,d, 20c,d, 24c,d, and 25c,d for the ion channel binding site of the NMDA receptor, for mu-, kappa-, and sigma-receptors have been investigated. In the group of tricyclic compounds only 19d shows remarkable sigma-receptor affinity (Ki = 21.6/1.10 microM). In the 1,3-dioxane series the moderate mu- (Ki = 27.8 microM) and kappa-receptor affinity (Ki = 36 microM) as well as the high sigma-receptor affinity (Ki = 3.3 microM) of the (S,S,S)-configurated methylamine 24c should be emphasized. The pentan-1-ol 26, the side product isolated during the synthesis of 24c, is of particular interest because of its considerable affinity to mu- (Ki = 16.0 microM), kappa- (Ki = 2.8 microM), and sigma-receptors (Ki = 14.5/1.26 microM). The biphasic competition curves obtained during sigma-receptor binding studies of 19d and 26 (two Ki values) may be explained by different interaction with sigma-receptor subtypes.
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Affiliation(s)
- B Wünsch
- Pharmazeutisches Institut der Universität Freiburg, Germany
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14
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Carroll FI, Bai X, Dehghani A, Mascarella SW, Williams W, Bowen WD. Asymmetric synthesis of 9-alkyl-2-benzyl-6,7-benzomorphans: characterization as novel sigma receptor ligands. J Med Chem 1999; 42:4621-9. [PMID: 10579824 DOI: 10.1021/jm990169r] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A convenient enantioselective synthesis of (1R,5R,9R)- and (1S,5S, 9S)-9-alkyl-2-benzyl-6,7-benzomorphans (2a-c) which starts with naphthaldehyde is described. These compounds were designed to gain additional information on the structure-sigma binding relationship of the 6,7-benzomorphan class of sigma ligands. In contrast to pentazocine and most 6,7-benzomorphans, the (1R,5R,9R)-isomers of 2a-c showed greater affinity for the sigma(1) receptor than the (1S, 5S,9S)-isomers. Despite reversal of enantioselectivity at the sigma(1) sites, moderate affinity and enantioselectivity at the sigma(2) sites [greater affinity for (1R,5R,9R)-isomers than (1S,5S, 9S)-isomers] were maintained. A comparison of the binding affinities of 2a-c to the more conformationally flexible trans-2-alkyl-1-benzaminoethyl-1,2-dihydronaphthalenes (10a-c) suggested that the relatively rigid structure of 2a-c played an important part in their sigma(1) binding properties. These compounds, particularly (1R,5R,9R)-2-benzyl-9-methyl-6,7-benzomorphan [(-)-2a], which has a K(i) value of 0.96 nM, will be useful in further characterization of the sigma(1) receptor.
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Affiliation(s)
- F I Carroll
- Chemistry and Life Sciences, Research Triangle Institute, Research Triangle Park, North Carolina 27709, USA
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15
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Abstract
[formula: see text] Concise asymmetric syntheses of several benzomorphan derivatives have been accomplished using enantiopure 2,3-dihydro-4-pyridones as chiral building blocks.
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Affiliation(s)
- D L Comins
- Department of Chemistry, North Carolina State University, Raleigh 27695-8204, USA.
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16
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Ronsisvalle G, Marrazzo A, Prezzavento O, Pasquinucci L, Vittorio F, Pittalà V, Pappalardo MS, Cacciaguerra S, Spampinato S. (+)-cis-N-ethyleneamino-N-normetazocine derivatives. Novel and selective sigma ligands with antagonist properties. J Med Chem 1998; 41:1574-80. [PMID: 9572883 DOI: 10.1021/jm970333f] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A series of (+)-cis-N-normetazocine derivatives has been described, and their affinities for sigma1, sigma2, and phencyclidine (PCP) sites and opioid, muscarinic (M2), dopamine (D2), and serotonin (5-HT2) receptors were evaluated. The effect of the N-substitution with a substituted ethylamino spacer was investigated. Compounds 8c-11c displayed high affinities for sigma1 sites and for opioid receptors. Substitution of the second basic nitrogen either with alkyl or cycloalkyl substituents give compounds (1a-6a) with high affinity and selectivity for sigma1 binding sites. Compounds 1a-5a were further characterized in vivo, and their agonist/antagonist activity was evaluated. In mouse, compound 1a and 2a as well as haloperidol suppressed in a dose-related manner the stereotyped behavior induced by (+)-SKF 10,047. Compounds 3a-5a and (+)-pentazocine do not affect the stereotyped behavior induced by ip injection of (+)-SKF 10,047. Therefore, from this series of compounds we identified potent and selective sigma1 ligands which might prove useful to unveil the functional role of sigma1 sites.
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Affiliation(s)
- G Ronsisvalle
- Department of Pharmaceutical Sciences, University of Catania, Viale Andrea Doria, 6, 95125 Catania, Italy
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17
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Grauert M, Bechtel WD, Ensinger HA, Merz H, Carter AJ. Synthesis and structure-activity relationships of 6,7-benzomorphan derivatives as antagonists of the NMDA receptor-channel complex. J Med Chem 1997; 40:2922-30. [PMID: 9288174 DOI: 10.1021/jm970131j] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We have synthesized a series of stereoisomeric 6,7-benzomorphan derivatives with modified N-substituents and determined their ability to antagonize the N-methyl-D-aspartate (NMDA) receptor-channel complex in vitro and in vivo. The ability of the compounds to displace [3H]-MK-801 from the channel site of the NMDA receptor in rat brain synaptosomal membranes and to inhibit NMDA-induced lethality in mice was compared with their ability to bind to the mu opioid receptor. Examination of structure-activity relationships showed that the absolute stereochemistry is critically important for differentiating these two effects. (-)-1R,9 beta,2"S-enantiomers exhibited a higher affinity for the NMDA receptor-channel complex than for the mu opioid receptor. The aromatic hydroxy function was also found to influence the specificity of the compounds. Shift of the hydroxy group from the 2'-position to the 3'-position significantly increased the affinity for the NMDA receptor-channel complex and considerably reduced the affinity for the mu opioid receptor. From this series of 6,7-benzomorphan derivatives, the compound 15cr.HCl [(2R)-[2 alpha, 3(R*),6 alpha]-1,2,3,4,5,6-hexahydro-3-(2-methoxypropyl)-6,11,11-trimethyl -2,6-methano-3-benzazocin-9-ol hydrochloride] was chosen as the optimum candidate for further pharmacological investigations.
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Affiliation(s)
- M Grauert
- Department of Medicinal Chemistry, Boehringer Ingelheim, KG, Ingelheim am Rhein, Federal Republic of Germany
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18
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Affiliation(s)
- B Wünsch
- Pharmazeutisches Institut der Albert-Ludwigs-Universität Freiburg
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19
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Danso-Danquah R, Bai X, Zhang X, Mascarella SW, Williams W, Sine B, Bowen WD, Carroll FI. Synthesis and sigma binding properties of 2'-substituted 5,9 alpha-dimethyl-6,7-benzomorphans. J Med Chem 1995; 38:2978-85. [PMID: 7636860 DOI: 10.1021/jm00015a022] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The synthesis and sigma 1 and sigma 2 binding properties of several (+)- and (-)-2-benzyl- and 2-dimethylallyl-2'-substituted-5,9 alpha-dimethyl-6,7-benzomorphans (3 and 4) are presented. In agreement with previously reported binding data for 2-substituted 5,9 alpha-dimethyl-2'-hydroxy-6,7-benzomorphans (N-substituted-N-normetazocine), all (1S,5S,9S)-(+)-isomers showed higher affinity for the sigma 1 site than the corresponding (1R,5R,9R)-(-)-isomers. Replacement of the 2'-hydroxy group of (+)-2-benzyl-5,9 alpha-dimethyl-2'-hydroxy-6,7-benzomorphan [(+)-1f] with a 2'-NH2 and 2'-N(CH3)2 [(+)-3b and (+)-3c, respectively] had only a small effect on the sigma 1 Ki values. Changing the 2'-hydroxy group of (+)-1f to an H, F, Cl, Br, I, NHAc, or NHSO2CH3 resulted in a 5-fold or greater loss in potency. In contrast, replacement of the 2'-hydroxy group of (+)-2-(dimethylallyl)-5,9 alpha-dimethyl-2'-hydroxy-6,7-benzomorphan [(+)-1b, (+)-pentazocine] with a 2'-H or 2'-F group resulted in a 2-fold increase in potency. Conversion of (+)-1f to its 2'-desoxy analogue (+)-2d resulted in a 27.5-fold loss in affinity. This suggests that (+)-1f and other N-substituted benzomorphan analogues may be binding to single sigma 1 receptors in a different way or to different sigma 1 receptors. (-)-Pentazocine [(-)-1b] and its 2'-fluoro analogue, (-)-2-(dimethylallyl)-5,9 alpha-dimethyl-2'-fluoro-6,7-benzomorphan [(-)-4a] showed the highest potency for the sigma 2 binding site.
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Affiliation(s)
- R Danso-Danquah
- Research Triangle Institute, Research Triangle Park, North Carolina 27709, USA
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20
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Brufani M, Filocamo L, Imbriani E, Lappa S, Mannina L. Synthesis of 2'-heptylcarbamoyloxy-2-methyl-6,7-benzomorphan: a new analogue of heptylphysostigmine (MF 201). Farmaco 1994; 40:743-5. [PMID: 7832976] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The synthesis of 2'-heptylcarbamoyloxy-2-methyl-6,7-benzomorphan is described. The compound is structurally related to the cholinesterase inhibitor heptylphysostigmine (MF 201) because the angular methyl group of the esoroline nucleus has been changed into a bridging carbon and the anilinic nitrogen has been replaced by a methylene group. This compound proved to be a potent cholinesterase in vitro inhibitor.
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Affiliation(s)
- M Brufani
- Dipartimento di Scienze Biochimiche, A. Rossi Fanelli, Università La Sapienza, Roma
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21
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Wünsch B, Höfner G, Bauschke G. [2,6-Epoxy-3-benzazocines: centrally acting N/O-acetals produced by cyclization of amino- and amidoacetals]. Arch Pharm (Weinheim) 1993; 326:127-33. [PMID: 8481093 DOI: 10.1002/ardp.19933260303] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Under acidic conditions the secondary amines 10a and 10b, the primary amine 15, the amide 17a, and the urethane 17b were cyclized to yield the 2,6-epoxy-3-benzazocines 11a, 11b, 16, 18a and 18b, respectively. Ring closure of the inverse amide 5a, however, failed to give the tricyclic N/O-acetal 6. With LiAlH4 the epoxy bridge of the urethane 18b was opened to afford the bicyclic 3-benzazocine 20. While the N-(2-methoxyethyl) derivative 11b did not influence the behaviour of mice, the N-methyl derivative 11a showed strong central effects.
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Affiliation(s)
- B Wünsch
- Institut für Pharmazie und Lebensmittelchemie der Universität München
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22
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Wünsch B, Bauschke G. [Benzomorphan analogs with doxpicomine partial structure: synthesis andpsychopharmacologic investigations of 5-aminomethyl- and 5-(alpha-aminobenzyl)- substituted 2,6-epoxy-3-benzoxocines]. Arch Pharm (Weinheim) 1993; 326:171-80. [PMID: 8481096 DOI: 10.1002/ardp.19933260311] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Addition of the beta-alanine derivative 6 to the homophthalaldehyde monoacetal 5 and subsequent LiAlH4-reduction led to the dihydroxy acetal 8, which was cyclized with acid to give the 5-aminomethyl-2,6-epoxy-3-benzoxocines 2a and 2b. The reaction of 5 with the anion of the beta-lactam 9 yielded two separable diastereomers: 10a with u,l-configuration and 10b with 1,1-configuration. Via the 2-benzopyran 11a (11b), the aminoalcohol 12a (12b), and the secondary amine 13a (13b), the beta-lactam adduct 10a (10b) was transformed to give the 5-(alpha-dimethylaminobenzyl)-2,6-epoxy-3-benzoxocine 3d (3b). The relative configurations of all these "beta-lactam route" products (10-13, 3d, and 3b) were established by their 1H-NMR-spectra. Attempts failed to get the missing diastereomers 3a and 3c by epimerization of the beta-lactams 11a and 11b or by reductive amination of the benzoyl derivatives 17a and 17b. Finally, 3a and 3c were obtained by phenylmagnesium bromide addition to the nitriles 21a and 21b, followed by LiAlH4-reduction, formaldehyde/NaBH3CN methylation and chromatographic separation. In the Irwin-screen (mouse) only 2a.HCl, 3b, and 3d (100 mg/kg body weight) caused weak central effects.
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Affiliation(s)
- B Wünsch
- Institut für Pharmazie und Lebensmittelchemie, Universität München
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23
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de Costa B, Radesca L, Dominguez C, Di Paolo L, Bowen WD. Synthesis and receptor binding properties of fluoro- and iodo-substituted high affinity sigma receptor ligands: identification of potential PET and SPECT sigma receptor imaging agents. J Med Chem 1992; 35:2221-30. [PMID: 1319493 DOI: 10.1021/jm00090a012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Unlabeled fluoro- and iodo-substituted ligands exhibiting very high affinity and selectivity for sigma receptors were synthesized based on three different structural classes of sigma receptor ligands. These compounds were evaluated for sigma receptor affinity and specificity in order to assess their potential as PET/SPECT imaging agents. Thus, (+)- and (-)-N-(5-fluoro-1-pentyl)normetazocines [(+)- and (-)-4] based on the (+)-benzomorphan class of sigma ligands were synthesized via N-alkylation of optically pure (+)- and (-)-normetazocine with 5-[(methylsulfonyl)oxy]-1-pentyl fluoride (11). (+)- and (-)-4 displaced [3H](+)-3-PPP with Ki values of 0.29 and 73.6 nM and [3H](+)-pentazocine with Ki values of 10.5 and 38.9 nM, respectively. The second class of PET/SPECT ligands was based upon the N-(arylethyl)-N-alkyl-2-(1-pyrrolidinyl)ethylamine class of sigma ligands; N-[2-(3,4-dichlorophenyl)-1-ethyl]-N-(3-fluoro-1-propyl)-2-(1- pyrrolidinyl)ethylamine (5) was obtained via N-alkylation of N-[2-(3,4-dichlorophenyl)-1-ethyl]-2-(1-pyrrolidinyl)ethylamine (14) with 3-fluoropropyl p-toluenesulfonate. 5 exhibited Ki values of 4.22 and 5.07 nM for displacement of [3H](+)-3-PPP and [3H](+)-pentazocine, respectively, comparable with the parent N-propyl compound. Attempts to synthesize N-[2-(3,4-dichlorophenyl)-1-ethyl]-N-[3- [(methylsulfonyl)oxy]-1-propyl]-2-(1-pyrrolidinyl)ethylamine (26), a precursor to 5 that could conceivably be converted to [18F]-5 by treatment with 18F-, proved unsuccessful. The sequence of regioselective nitration, catalytic hydrogenation, and diazotization followed by NaI quench of N-[2-(3,4-dichlorophenyl)-1-ethyl]-N-methyl-2-(1- pyrrolidinyl)ethylamine (2) afforded the iodinated ethylenediamine N-[2-(2-iodo-4,5-dichlorophenyl)-1-ethyl]-N-methyl-2-(1- pyrrolidinyl)ethylamine (8), a potential SPECT ligand for sigma receptors. This compound showed an affinity of 0.54 nM ([3H](+)-3-PPP) comparable with the parent compound 2 (Ki = 0.34 nM, [3H](+)-3-PPP). Ligand 8 exhibited a similar potency against [3H](+)-pentazocine. The third class of high-affinity sigma receptor ligands was rationalized based on rearrangement of the bonds in ethylenediamine 2 to give 1-[2-(3,4-dichlorophenyl)-1-ethyl]-4-(1-propyl)piperazine (3). This compound exhibited very high affinity (Ki = 0.31 nM, [3H](+)-3-PPP) and selectivity for sigma receptors.(ABSTRACT TRUNCATED AT 400 WORDS)
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Affiliation(s)
- B de Costa
- Laboratory of Medicinal Chemistry, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892
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24
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Klein P, Nelson WL. Electrophilic gamma-lactone kappa-opioid receptor probes. Analogues of 2'-hydroxy-2-tetrahydrofurfuryl-5,9-dimethyl-6,7-benzomorphan diastereomers. J Med Chem 1991; 34:2438-44. [PMID: 1652019 DOI: 10.1021/jm00112a019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Benzomorphans with an electrophilic group in the nitrogen substituent were prepared as potentially irreversible ligands for the kappa-opioid receptor. These were synthesized from products of the reaction of normetazocine with the enantiomers of 5-(iodomethyl)-gamma-butyrolactone (11). alpha-Methylene gamma-lactones 5 and 7 and endocyclic alpha,beta-unsaturated gamma-lactones 8 and 9 were prepared from the corresponding saturated gamma-lactones 13 and 23 possessing the "active" (1R,5R,9R)-benzomorphan stereochemistry. Only gamma-lactones 8, 9, 13, and 23, lacking the exocyclic methylene group, retain significant affinities for opioid receptor binding sites when compared with the reference compounds (2"S)-3 and (2"R)-3. As observed with these references compounds, greater binding affinity is also seen with gamma-lactone diastereomers having the 2"S stereochemistry in the nitrogen substituent. Although the gamma-lactones do not bind irreversibly in opioid receptor preparations, they do show kappa-receptor selectivities comparable to those observed for the reference compounds.
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Affiliation(s)
- P Klein
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle 98195
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25
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Hori M, Iwamura T, Morita T, Imai E, Oji H, Kataoka T, Shimizu H, Ban M, Nozaki M, Niwa M. Facile synthesis of 8-benzoylthio-2,6-methano-3-benzazocines and 3-benzoylthiomorphinans having small-ring substituents. Chem Pharm Bull (Tokyo) 1989; 37:2222-4. [PMID: 2557165 DOI: 10.1248/cpb.37.2222] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Synthesis of 3-cyclopropylmethyl-, 3-cyclobutylmethyl-, and 3-methyl-8-benzoylthio-2,6-methano-3-benzazocines (1j-l) was performed by regio-selective chlorosulfonation of non-narcotic 8-deoxy derivatives (1a-c) followed by reduction and benzoylation. 3-Benzoylthiomorphinans (2h-j) were also obtained by the same method. Compounds having small-ring substituents (1k, 1l, 2i, 2j) were found to be weak but pure mu- and delta-opioid antagonists. The analgetic activity of 1k was almost equal to that of pentazocine.
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26
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Verlinde CL, Blaton NM, De Ranter CJ, Peeters OM. Structure of a kappa-opioid receptor misfit: (1S,5R,8R,9R)-2'-hydroxy-5,9-dimethyl-8,2-epoxyethano-6,7-benzomorphan hydrochloride. Acta Crystallogr C 1989; 45 ( Pt 5):799-803. [PMID: 2557866 DOI: 10.1107/s0108270189002258] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
C16H22NO+2.Cl-, Mr = 295.808, monoclinic, P2(1), a = 11.967 (1), b = 12.529 (1), c = 9.9369 (9) A, beta = 93.00 (1) degrees, V = 1487.8 (2) A3, Z = 4, Dm = 1.32 (2), Dx = 1.321 Mg m-3, lambda(Cu K alpha) = 1.54178 A, mu(Cu K alpha) = 2.289 mm-1, F(000) = 632, T = 291 K, final R = 0.040 for 2448 observed reflections. The two molecules present in the asymmetric unit are linked by an extensive network of hydrogen bonds, including several of the less common (C-)H...O and (C-)-H...Cl types. This interpretation is substantiated by a Mulliken population analysis resulting from CNDO/2 calculations. The major effect of the presence of the epoxyethano bridge is a marked flattening about the N atom of the piperidinium ring. Whether this is sufficient to explain the inactivity of the compound at the opioid kappa receptor is not clear.
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Affiliation(s)
- C L Verlinde
- Instituut voor Farmaceutische, Wetenschappen, Katholieke Universiteit Leuven, Belgium
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Jacobson AE, Rice KC, Burke TR, Lupinacci L, Mattson MV, Aceto MD, Harris LS. 2,5-Dimethyl-2'-hydroxy-9 alpha- and 9 beta-(3-methylbutyl)-6,7-benzomorphans and N-substituted compounds in the 9 alpha-(3-methylbutyl) series: chemistry, pharmacology, and biochemistry. J Pharm Sci 1987; 76:248-52. [PMID: 3035172 DOI: 10.1002/jps.2600760315] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
2,5-Dimethyl-2'-hydroxy-9 alpha-(3-methylbutyl)-6,7-benzomorphan, the 9 beta-analogue, and 9 alpha-N-substituted (N-ethyl, propyl, butyl, pentyl, hexyl, phenylethyl, allyl, and cyclopropylmethyl) compounds were synthesized and evaluated biochemically and pharmacologically. The 9 beta N-methyl compound was found to be as potent as morphine in the mouse hot plate assay and had one-seventh the affinity of morphine for the opioid receptor. The N-alkyl and N-phenethyl 9 alpha-substituted compounds were either inactive or relatively ineffective as antinociceptive agents. None of the examined compounds substituted for morphine in single-dose suppression studies in the rhesus monkey. The N-cyclopropylmethyl compound in the 9 alpha series had half the narcotic antagonist potency of nalorphine and one-eighth of its affinity for the opioid receptor. The 9 alpha-(3-methylbutyl) moiety, unlike bulky substituents in the 9 beta position of 6,7-benzomorphans, generally lowers affinity for the mu opioid receptor and diminishes their in vivo activity as agonists or antagonists.
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Abstract
The synthesis of four 3-substituted 6-tert-butyl-1,2,3,4,5,6-hexahydro-2,6-methano-3-benzazocines is described. Derivatives with N-Me or N-phenethyl substituents do not differ significantly in their antinociceptive properties from compounds bearing 6-H or 6-Me; however, they are less active than 6-Ph analogues.
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30
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Hori M, Imai E, Kawamura N, Iwamura T, Kataoka T, Shimizu H. Synthesis of some N-substituted 1,2,3,4,5,6-hexahydro-2,6-methano-3-benzazocines (6,7-benzomorphans). Chem Pharm Bull (Tokyo) 1985; 33:1707-10. [PMID: 4042247 DOI: 10.1248/cpb.33.1707] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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31
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Rice KC, Konicki PE, Quirion R, Burke TR, Pert CB. Synthesis and pharmacological characterization of (+/-)-5,9 alpha-dimethyl-2-[2-(4-fluorophenyl)ethyl]-2'-hydroxy-6,7-benzomorphan (fluorophen), a ligand suitable for visualization of opiate receptors in vivo. J Med Chem 1983; 26:1643-5. [PMID: 6313921 DOI: 10.1021/jm00365a017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
A fluorinated derivative of the benzomorphan opiate agonist phenazocine, (+/-)-5,9 alpha-dimethyl-2-[2-(4-fluorophenyl)ethyl]-2'-hydroxy-6, 7-benzomorphan (fluorophen), was prepared by N-acylation of (+/-)-5,9 alpha-dimethyl-2'-hydroxybenzomorphan with (p-fluorophenyl)acetyl chloride, followed by diborane reduction of the resulting amide. Fluorination produces only a twofold opiate receptor affinity loss when measured either by bioassay or receptor binding (selectivity mu congruent to delta greater than kappa). Labeled with 18F, fluorophen should be sufficiently potent to be useful as an in vivo probe for visualizing opiate receptors by positron emission transaxial tomography (PETT).
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33
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Pant J, Pant KK, Gupta TK, Bhargava KP, Joshi BC. Synthesis and pharmacological studies of 2'-sulphonyl[3-(3H-2,4-disubstituted-1,5-benzodiazepino)]-2,5-dimethyl-6,7-benzomorphans. Pharmazie 1982; 37:176-7. [PMID: 7100235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
2'-Sulphonyl[3-(3H-2,4-dimethyl-1,5-benzodiazepino)]-2,5-dimethyl-6,7-ben zomorphan (3a), 2'-sulfonyl[3-(3H-2 methyl-4-phenyl-1,5-benzodiazepino)]-2,5-dimethyl-6,7-benzomorphan (3b) and 2'-sulfonyl [3-(3H-2-methyl-4-oxo-5H-1.5-benzodiazepino)]-2,5-dimethyl-6,7-benzomorphan (3c), synthesized from 2,5-dimethyl-6,7-benzomorphan (1) in three steps via chlorosulphonation, condensation with sodium salt of acetylacetone, benzoylacetone and ethyl acetoacetate separately and condensation with o-phenylenediamine, were studied for their pharmacological activities. It was found that 3a has mild CNS depressant, analgesic and anticonvulsant (against petit mal type of seizures) activities. 3b has significant anti-depressant and mild analgesic activities while 3c has CNS depressant, mild analgesic and anticonvulsant activities (against petitmal type seizures).
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34
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Bélanger PC, Scheigetz J, Young RN, Charleson SE, Hudgin RL, Engelhardt EL. Preparation and analgesic properties of amino acid derivatives of (-)-5,9 alpha-diethyl-2'-hydroxybenzomorphan. J Med Chem 1981; 24:1297-9. [PMID: 6273560 DOI: 10.1021/jm00143a007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The N-arginyl derivative of methionine-enkephalin (fragment 60-65 of beta-lipotropin) has been shown to be equiactive with the parent pentapeptide, despite the fact that the tyrosine amino group in this compound has been neutralized by the formation of an amide linkage. A series of N-(amino acid) derivatives of (-)-5,9 alpha-diethyl-2'-hydroxybenzomorphan was prepared and evaluated for analgesic activity. In vitro activities were found to vary greatly, depending on the nature of the amino acid used. The N-arginyl derivative was found to be equipotent to (-)-5,9 alpha-diethyl-2'hydroxybenzomorphan and also to methionine-enkephaline in the naloxone binding assay.
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Reifenrath WG, Roche EB, Al-Turk WA, Johnson HL. Synthesis and biological activity of fluoroalkylamine derivatives of narcotic analgesics. J Med Chem 1980; 23:985-90. [PMID: 6106064 DOI: 10.1021/jm00183a005] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
N-Ethyl-, N-(2-fluoroethyl)-, N-(2,2-difluoroethyl)-, and N-(2,2,2-trifluoroethyl)-substituted normeperidine (1b-e) and normetazocine (2b-e) derivatives were prepared. The analgesic activities of the compounds were determined in mice. Opiate receptor binding studies, in the presence and absence of sodium ion, were carried out. The antagonist activities of normetazocine derivatives were studied in monkeys. These were further examined in the isolated guinea pig ileum for relative agonist activity. The pKa values were measured; in vivo agonist acitivty was lost with weakly basic derivatives. For the normetazocine derivatives, opiate receptor binding data were consistent with guinea pig ileum agonist potency and mouse vas deferens antagonist potency but not with in vivo data. Opiate receptor binding was reduced for the less basic normetazocine derivatives. In the normeperidine series, there was no apparent direct relationship between pKa and opiate receptor binding. However, a relationship involving the hydrophobic character of the N-substituent is discussed. The N-(2-fluoroethyl) derivatives in both series were found to cause convulsions in rats at doses of 40-45 mg/kg ip. Elevated serum citrate levels were found in these rats, implicating in vivo oxidative deamination of the N-(fluoroalkyl) substituent to fluoroacetate.
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Bellora E, Cereda E, Ezhaya A, Marazzij-Uberti E, Pala G, Donetti A. Synthesis and analgesic activity of N-substituted 6,7-benzomorphans. Farmaco Sci 1980; 35:490-7. [PMID: 7450042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Some new N-substituted 6,7-benzomorphans were prepared and tested for analgetic activity. The compounds (I) and (II), which proved the most active in a preliminary screening, were submitted to a more detailed investigation, and their ED50 was determined in mice by the phenylquinone, hot-plate and tail-pinch tests. Studies of acute toxicity and physical dependence capacity were also performed.
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Merz H, Stockhaus K. N-[(Tetrahydrofuryl)alkyl] and N-(alkoxyalkyl) derivatives of (-)-normetazocine, compounds with differentiated opioid action profiles. J Med Chem 1979; 22:1475-83. [PMID: 43894 DOI: 10.1021/jm00198a009] [Citation(s) in RCA: 58] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Abstract
The N-(2-cyanoethyl)-9alpha-ethyl-5-methyl-6,7-benzomorphan (1c) is a more potent antinociceptive and has stronger receptor binding affinity than its N-methyl analogue 1b. The N-(2-cyanoethyl)-4-phenylpiperidine compounds 2b and 3b were almost inactive compared to their N-methyl congeners 2a and 3a, respectively. It appears that the pharmacological effect of the N-(2-cyanoethyl) moiety is dependent on the opioid on which it is substituted.
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Yokoyama N, Almaula PI, Block FB, Granat FR, Gottfried N, Hill RT, McMahon EH, Munch WF, Rachlin H, Saelens JK, Siegel MG, Tomaselli HC, Clarke FH. Syntheses, analgetic activity, and physical dependence capacity of 5-phenyl-6,7-benzomorphan derivatives. J Med Chem 1979; 22:537-53. [PMID: 37335 DOI: 10.1021/jm00191a016] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The synthesis, analgetic activity, and physical dependence capacity of a large number of 5-phenyl-6,7-benzomorphan derivatives are described. Observations made during the Stevens' rearrangement of 1-benzyl-1-methyl-delta 3-piperidinium salt derivatives (V) under various conditions are discussed. The absolute configuration of the 9-demethyl series and the 2'-deoxy series is established by comparison of their ORD and CD spectra with those of 49, whose absolute configuration was previously established by X-ray crystallography. A convenient synthesis of 3H-labeled phenols using 3H3PO4 is described, as well as the preparation of 14C-labeled compounds by conventional methods.
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Abstract
The benzomorphan analogues, 8-hydroxy-3-methyl-2,3,4,5-tetrahydro-1,4-methano-1H-3-benzazepine (1), 8-hydroxy-2-methyl-2,3,4,5-tetrahydro-1,4-methano-1H-2-benzazepine (2), 9-hydroxy-2-methyl-1,2,3,4,5,6-hexahydro-1,5,-methano-2-benzazocine (3), and 10-hydroxy-2-methyl-2,3,4,5,6,7-hexahydro-1,6-methano-1H-2-benzazonine (4), have been synthesized in order to evaluate their analgetic activity. Only slight analgetic activity was found in any of these compounds. The importance of nitrogen to aromatic ring distance for the analgetic-receptor interaction is discussed.
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Abstract
3-Methoxy-8-oxamorphinans 9 have been prepared from the corresponding 5-allyl-9alpha-hydroxy-2'-methoxy-2-methyl-6,7-benzomorphans 7. The former compounds were transformed to the 3-hydroxy-8-oxamorphinans 6, a class of potent analgesics and analgesic-antagonists. In ring C of the morphinan nucleus substitution of 8-CH2 with oxygen enhanced both analgesic and antagonist activities, while replacement of hydrogen with a methyl group at C-14 in these compounds enhanced antagonist activity and decreased analgesic activity. Tetrahydrofuranobenzomorphans 3 and 3-hydroxy-8-oxaisomorphinans 4 displayed lower levels of activity. Structural requirements for antagonist activity are discussed.
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Uwaydah IM, May EL, Harris LS. Synthesis and pharmacological activity of some N-alkyl-substituted 9alpha-ethyl-2'-hydroxy-5-methyl-6,7-benzomorphans. J Med Chem 1977; 20:1374-7. [PMID: 21291 DOI: 10.1021/jm00221a004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A series of N-substituted 9alpha-ethyl-2'-hydroxy-5-methyl-6,7-benzomorphans was synthesized and evaluated for their narcotic analgesic and antagonistic activities. Compounds 2a and 22 were as potent as morphine in the writhing (PPQ) and hot-plate tests, while a number of compounds demonstrated antagonistic activities greater than nalorphine. Generally, the compounds in this series show activities somewhat greater than the comparable compounds in the 5,9alpha-dimethyl-6,7-benzomorphan series for analgesic effect and similar or slightly less antagonistic potency.
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Saucier M, Daris JP, Lambert Y, Monkovié, pircio AW. 5-allyl-9-oxobenzomorphans. 3. Potent narcotic antagonists and analgesics-antagonists in the series of substituted 2',9beta-dihydroxy-6,7-benzomorphans. J Med Chem 1977; 20:676-82. [PMID: 16134 DOI: 10.1021/jm00215a012] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
5-Allyl-2'-methoxy-2-methyl-9-oxo-6,7-benzomorphan methiodide (1) has been converted in a selective two-step process to the corresponding 9beta-hydroxy intermediates 4 and 6, which in turn were transformed via modified von Braun demethylation-acylation to the amides 11 and 21, respectively. These were reduced and demethylated to give a series of 5-allyl-2',9beta-dihydroxy-2-substituted 6,7-benzomorphans 13 and 23, some of which have been found to be highly potent narcotic antagonists and/or analgesics. The resolution of the most interesting compounds (23a and 23b) and pharmacological properties of the optical isomers are also described. Reduction of the double bond in 13 and 23 to give 14 and 24, with one exception, did not appreciably alter pharmacological profiles, while cyclization to the tetrahydrofuranobenzomorphans 25 substantially reduced the level of activities.
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Rice KC, Shiotani S, Creveling CR, Jacobson AE, Klee WA. N-(2,4,5-Trihydroxyphenehtyl)normetazocine, a potential irreversible inhibitor of the narcotic receptor. J Med Chem 1977; 20:673-5. [PMID: 16133 DOI: 10.1021/jm00215a011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The reaction of N-2,4,5-tribenzyloxyphenyl)ethyl methanesulfonate, prepared in a seven-step sequence, with normetazocine followed by hydrogenolysis of the benzyloxy-protecting groups, gave N-(2,4,5-trihydroxyphenethyl)normetazocine. This compound was prepared to study the effect of a narcotic analgesic containing a functional group which could be activated in situ to a moiety potentially capable of reacting irreversibly with the narcotic receptor. This 6-hydroxydopamin derivative of normetazocine did not prove to be a useful affinity label. Its low toxicity could indicate the necessity for the formation of an aminochrome system for the expression of toxicity by 6-hydroxydopamine.
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Rice KC, Klee WA, Aceto MD, Swain HH, Jacobson AE. Potential long acting opiate antagonists: preparation, pharmacological activity, and opiate-receptor binding of N-substituted 2'-hydroxy-5-methyl-9 alpha-propyl-6,7-benzomorphans. J Pharm Sci 1977; 66:193-7. [PMID: 190376 DOI: 10.1002/jps.2600660215] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
A homologous series of N-substituted 2'-hydroxy-5-methyl-9 alpha-propyl-6,7-benzomorphans (hydrogen to octyl inclusive, allyl, and cyclopropylmethyl) was prepared. In contradistinction to the normetazocine, normorphine, and (-)-3-hydroxymorphinan series, the N-pentyl and N-hexyl derivatives do not have the analgesic potency of the parent N-methyl compound; instead, they are narcotic antagonists with a long duration of action. All of the N-substituted 9 alpha-propylbenzomorphans, except for methyl, heptyl, and octyl, have antagonist activity. The receptor binding constants of the N-alkyl compounds are uniformly two- to threefold lower than those of the N-substituted normetazocines.
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Shiotani S, Kometani T. 10-Hydroxy-4-methyl-2,3,4,5,6,7-hexahydro-1,6-methano-1H-4-benzazonine derivatives (homobenzomorphans) as analgesics. J Med Chem 1976; 19:803-6. [PMID: 7674 DOI: 10.1021/jm00228a013] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Six 10-hydroxy-4-methyl-2,3,4,5,6,7-hexahydro-1,6-methano-1H-4-benzazonine derivatives 17a-f have been synthesized as potential analgesics. The synthesis of these compounds involved conversion of 4-(2-dimethylaminoethyl)-6-methoxy alpha tetralone derivatives 12a-f to their N-methyl analogues and the subsequent intramolecular mannich reaction with formaldehyde to give the 7-keto C-ring homobenzomorphans 14a-f from which 17a-f, respectively, were obtained. Compounds 17a-f are as potent as morphine as analgesics (mice).
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Rice KC, Jacobson AE. Optical resolution of (+/-)-2,5-dimethyl-2'-hydroxy-9alpha- and -9beta-propyl-6,7-benzomorphans and their pharmacological properties. J Med Chem 1976; 19:430-2. [PMID: 815550 DOI: 10.1021/jm00225a021] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The levo and dextro isomers of 2,5-dimethyl-2'-hydroxy-9alpha- and -9beta-propyl-6,7-benzomorphans have been prepared. The analgesic potency and physical dependence capacity of the optical isomers and their racemic parents were determined. The 9alpha-propyl levo isomer was analgesically equipotent with morphine; the 9beta-propyl levo isomer was considerably more potent subcutaneously and equipotent orally. None of the optical isomers suppressed the withdrawal syndrome; the 9beta-propyl levo isomer exacerbated the withdrawal syndrome.
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Abstract
2,9alpha-Dimethyl-2'-hydroxy-6,7-benzomorphan (14) has been synthesized in six to seven steps from trans-3,4-dihydro-4-(2-dimethylaminoethyl)-6-methoxy-3-methyl-1(2H)-naphthalenone (1). The key reaction of the sequence was mercuric acetate cyclization of trans-1,2-dihydro-1-(2-methylaminoethyl)-7-methoxy-2-methylnaphthalene (8) which gave a mixture of 9alpha-methyl-8alpha-hydroxy-6,7-benzomorphan (9, 49%), the corresponding acetate (10, 13%), and the 9beta-methyl-8alpha-hydroxy-6,7-benzomorphan (11, 5%). In the presence of Et3N, the yields were 16, 37, and 0%, respectively. Structural assignments are based on ir, NMR, and mass spectral data and on chemical conversions.
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