1
|
Ma H, Wang H, Gillespie JC, Mendez RE, Selley DE, Zhang Y. Exploring naltrexamine derivatives featuring azaindole moiety via nitrogen-walk approach to investigate their in vitro pharmacological profiles at the mu opioid receptor. Bioorg Med Chem Lett 2021; 41:127953. [PMID: 33766769 DOI: 10.1016/j.bmcl.2021.127953] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [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: 01/14/2021] [Revised: 02/25/2021] [Accepted: 02/26/2021] [Indexed: 11/19/2022]
Abstract
In the present work, we reported the application of a nitrogen-walk approach on developing a series of novel opioid ligands containing an azaindole moiety at the C6-position of the epoxymorphinan skeleton. In vitro study results showed that introducing a nitrogen atom around the indole moiety not only retained excellent binding affinity, but also led to significant functional switch at the mu opioid receptor (MOR). Further computational investigations provided corroborative evidence and plausible explanations of the results of the in vitro studies. Overall, our current work implemented a series of novel MOR ligands with high binding affinity and considerably low efficacy, which may shed light on rational design of low efficacy MOR ligands for opioid use disorder therapeutics.
Collapse
Affiliation(s)
- Hongguang Ma
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, 800 E Leigh Street, Richmond, VA 23298, United States
| | - Huiqun Wang
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, 800 E Leigh Street, Richmond, VA 23298, United States
| | - James C Gillespie
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, 410 North 12(th) Street, Richmond, VA 23298, United States
| | - Rolando E Mendez
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, 410 North 12(th) Street, Richmond, VA 23298, United States
| | - Dana E Selley
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, 410 North 12(th) Street, Richmond, VA 23298, United States
| | - Yan Zhang
- Department of Medicinal Chemistry, School of Pharmacy, Virginia Commonwealth University, 800 E Leigh Street, Richmond, VA 23298, United States.
| |
Collapse
|
2
|
Zádor F, Király K, Váradi A, Balogh M, Fehér Á, Kocsis D, Erdei AI, Lackó E, Zádori ZS, Hosztafi S, Noszál B, Riba P, Benyhe S, Fürst S, Al-Khrasani M. New opioid receptor antagonist: Naltrexone-14-O-sulfate synthesis and pharmacology. Eur J Pharmacol 2017; 809:111-121. [PMID: 28502630 DOI: 10.1016/j.ejphar.2017.05.024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [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: 11/11/2016] [Revised: 05/09/2017] [Accepted: 05/10/2017] [Indexed: 11/17/2022]
Abstract
Opioid antagonists, naloxone and naltrexone have long been used in clinical practice and research. In addition to their low selectivity, they easily pass through the blood-brain barrier. Quaternization of the amine group in these molecules, (e.g. methylnaltrexone) results in negligible CNS penetration. In addition, zwitterionic compounds have been reported to have limited CNS access. The current study, for the first time gives report on the synthesis and the in vitro [competition binding, G-protein activation, isolated mouse vas deferens (MVD) and mouse colon assay] pharmacology of the zwitterionic compound, naltrexone-14-O-sulfate. Naltrexone, naloxone, and its 14-O-sulfate analogue were used as reference compounds. In competition binding assays, naltrexone-14-O-sulfate showed lower affinity for µ, δ or κ opioid receptor than the parent molecule, naltrexone. However, the μ/κ opioid receptor selectivity ratio significantly improved, indicating better selectivity. Similar tendency was observed for naloxone-14-O-sulfate when compared to naloxone. Naltrexone-14-O-sulfate failed to activate [35S]GTPγS-binding but inhibit the activation evoked by opioid agonists (DAMGO, Ile5,6deltorphin II and U69593), similarly to the reference compounds. Schild plot constructed in MVD revealed that naltrexone-14-O-sulfate acts as a competitive antagonist. In mouse colon, naltrexone-14-O-sulfate antagonized the inhibitory effect of morphine with lower affinity compared to naltrexone and higher affinity when compared to naloxone or naloxone-14-O-sulfate. In vivo (mouse tail-flick test), subcutaneously injected naltrexone-14-O-sulfate antagonized morphine's antinociception in a dose-dependent manner, indicating it's CNS penetration, which was unexpected from such zwitter ionic structure. Future studies are needed to evaluate it's pharmacokinetic profile.
Collapse
Affiliation(s)
- Ferenc Zádor
- Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári krt. 62., H- 6726 Szeged, Hungary.
| | - Kornél Király
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, Semmelweis University, Nagyvárad tér 4, P.O. Box 370, H-1445 Budapest, Hungary
| | - András Váradi
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Semmelweis University, Hőgyes Endre u., 9., H-1092 Budapest, Hungary
| | - Mihály Balogh
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, Semmelweis University, Nagyvárad tér 4, P.O. Box 370, H-1445 Budapest, Hungary
| | - Ágnes Fehér
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, Semmelweis University, Nagyvárad tér 4, P.O. Box 370, H-1445 Budapest, Hungary
| | - Dóra Kocsis
- Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári krt. 62., H- 6726 Szeged, Hungary
| | - Anna I Erdei
- Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári krt. 62., H- 6726 Szeged, Hungary
| | - Erzsébet Lackó
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, Semmelweis University, Nagyvárad tér 4, P.O. Box 370, H-1445 Budapest, Hungary
| | - Zoltán S Zádori
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, Semmelweis University, Nagyvárad tér 4, P.O. Box 370, H-1445 Budapest, Hungary
| | - Sándor Hosztafi
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Semmelweis University, Hőgyes Endre u., 9., H-1092 Budapest, Hungary
| | - Béla Noszál
- Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Semmelweis University, Hőgyes Endre u., 9., H-1092 Budapest, Hungary
| | - Pál Riba
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, Semmelweis University, Nagyvárad tér 4, P.O. Box 370, H-1445 Budapest, Hungary
| | - Sándor Benyhe
- Institute of Biochemistry, Biological Research Centre of the Hungarian Academy of Sciences, Temesvári krt. 62., H- 6726 Szeged, Hungary
| | - Susanna Fürst
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, Semmelweis University, Nagyvárad tér 4, P.O. Box 370, H-1445 Budapest, Hungary
| | - Mahmoud Al-Khrasani
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, Semmelweis University, Nagyvárad tér 4, P.O. Box 370, H-1445 Budapest, Hungary.
| |
Collapse
|
3
|
Kong F, Zhu T, Pan W, Tsao R, Pagano TG, Nguyen B, Marquez B. WYE-120318, a ring contraction product of methylnaltrexone, and structure revision of coniothyrione. Magn Reson Chem 2012; 50:829-833. [PMID: 23135875 DOI: 10.1002/mrc.3892] [Citation(s) in RCA: 5] [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] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Revised: 09/19/2012] [Accepted: 09/25/2012] [Indexed: 06/01/2023]
Abstract
A contracted ring degradation product, WYE-120318 (compound 2), was discovered during the development phase for methylnaltrexone bromide (compound 1) drug substance. The compound was isolated by high-performance liquid chromatography fractionation, and its structure was determined by spectroscopic data analyses. WYE-120318 is formed from methylnaltrexone through a benzyl-benzilic acid type rearrangement reaction to yield an α-hydroxy-cyclopentanecarboxylic acid substructure. The proposed structure and the formation mechanism are confirmed by the synthesis of WYE-120318 from methylnaltrexone (compound 1). A similar benzyl-benzilic acid type rearrangement reaction can be envisioned as the biological origin of remisporine A (compound 3), a naturally occurring cyclopentadienyl compound that autocatalytically dimerizes to remisporine B (compound 4). The structure of remisporine A was deduced from its dimer 4. Coniothyione (compound 5) can be considered as the first example of a stable natural product bearing the remisporine A skeleton. However, the regiochemistry of the chlorosubstitution in the coniothyrione structure needs to be revised to compound 6 on the basis of the nuclear magnetic resonance data and biogenesis analysis.
Collapse
Affiliation(s)
- Fangming Kong
- Structure Elucidation Group, Pfizer Worldwide Research and Development, 445 East Point Road, Groton, CT 06340, USA.
| | | | | | | | | | | | | |
Collapse
|
4
|
Le Naour M, Lunzer MM, Powers MD, Portoghese PS. Opioid activity of spinally selective analogues of N-naphthoyl-β-naltrexamine in HEK-293 cells and mice. J Med Chem 2012; 55:670-7. [PMID: 22136373 PMCID: PMC3438918 DOI: 10.1021/jm200902v] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [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
Using the selective mu-kappa agonist, N-naphthoyl-β-naltrexamine 1, as the prototype ligand, a series of closely related naphthalene analogues were synthesized to study the chemical space around the naphthalene moiety in an effort to evaluate how receptor selectivity is affected by chemical modification. Nine analogues (2-10) of compound 1 were synthesized and tested on HEK-293 cells expressing homomeric and heteromeric opioid receptors, and in the mouse tail-flick assay. It was found that a small change in structure produces profound changes in selectivity in this series. This is exemplified by the discovery that introduction of a 6-fluoro group transforms 1 from a selective mu-kappa heteromeric receptor agonist to a delta-preferring agonist 7. The in vivo studies reveal that many of the ligands are more potent spinally than supraspinally and devoid of tolerance.
Collapse
MESH Headings
- Analgesics/chemical synthesis
- Analgesics/chemistry
- Analgesics/pharmacology
- Animals
- Calcium/metabolism
- Drug Partial Agonism
- Drug Tolerance
- Female
- HEK293 Cells
- Humans
- Injections, Spinal
- Ligands
- Male
- Mice
- Mice, Inbred ICR
- Mice, Knockout
- Naltrexone/analogs & derivatives
- Naltrexone/chemical synthesis
- Naltrexone/chemistry
- Naltrexone/pharmacology
- Protein Multimerization
- Receptors, Opioid, delta/agonists
- Receptors, Opioid, kappa/agonists
- Receptors, Opioid, mu/agonists
- Receptors, Opioid, mu/genetics
- Stereoisomerism
- Structure-Activity Relationship
Collapse
Affiliation(s)
- Morgan Le Naour
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis, Minnesota 55455
| | - Mary M. Lunzer
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis, Minnesota 55455
| | - Mike D. Powers
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis, Minnesota 55455
| | - Philip S. Portoghese
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis, Minnesota 55455
| |
Collapse
|
5
|
Zhang S, Yekkirala A, Tang Y, Portoghese PS. A bivalent ligand (KMN-21) antagonist for mu/kappa heterodimeric opioid receptors. Bioorg Med Chem Lett 2009; 19:6978-80. [PMID: 19892550 PMCID: PMC5060004 DOI: 10.1016/j.bmcl.2009.10.045] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [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] [Received: 09/07/2009] [Revised: 10/08/2009] [Accepted: 10/09/2009] [Indexed: 11/15/2022]
Abstract
In an effort to develop antagonists for kappa-mu opioid receptor heterodimers, a series of bivalent ligands 3-6 containing kappa- and mu-antagonist pharmacophores were designed and synthesized. Evaluation of the series in HEK-293 cells revealed 4 (KMN-21) to selectively antagonize the activation of kappa-mu heterodimers, suggesting possible bridging of receptors when the bivalent ligand spacer contains 21 atoms.
Collapse
Affiliation(s)
- Shijun Zhang
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota, USA
| | - Ajay Yekkirala
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota, USA
| | - Ye Tang
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota, USA
| | - Philip S. Portoghese
- Department of Medicinal Chemistry, University of Minnesota, Minneapolis, Minnesota, USA
| |
Collapse
|
6
|
Duval RA, Allmon RL, Lever JR. Indium-Labeled Macrocyclic Conjugates of Naltrindole: High-Affinity Radioligands for In Vivo Studies of Peripheral δ Opioid Receptors. J Med Chem 2007; 50:2144-56. [PMID: 17402725 DOI: 10.1021/jm0700013] [Citation(s) in RCA: 20] [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
We have identified a series of hydrophilic indium-labeled DOTA and DO3A conjugates of naltrindole (NTI) that are suited to in vivo studies of peripheral delta opioid receptors. Indium(III) complexes, linked to the indole nitrogen of NTI by six- to nine-atom spacers, display high affinities (0.1-0.2 nM) and excellent selectivities for binding to delta sites in vitro. The [111In]-labeled complexes can be prepared in good isolated yields ( approximately 65%) with high specific radioactivities (>3300 mCi/mumol). The spacers serve as pharmacokinetic modifiers, and log D7.4 values range from -2.74 to -1.79. These radioligands exhibit a high level of specific binding (75-94%) to delta opioid receptors in mouse gut, heart, spleen, and pancreas in vivo. Uptakes of radioactivity are saturable by the non-radioactive complexes, inhibited by naltrexone, and blocked by NTI. Thus, these radiometal-labeled NTI analogues warrant further study by single-photon emission computed tomography.
Collapse
Affiliation(s)
- Romain A Duval
- Departments of Radiology and the Radiopharmaceutical Sciences Institute, and Medical Pharmacology and Physiology, University of Missouri-Columbia, Columbia, Missouri 65212, USA
| | | | | |
Collapse
|
7
|
Peng X, Knapp BI, Bidlack JM, Neumeyer JL. Pharmacological properties of bivalent ligands containing butorphan linked to nalbuphine, naltrexone, and naloxone at mu, delta, and kappa opioid receptors. J Med Chem 2007; 50:2254-8. [PMID: 17407276 PMCID: PMC3357624 DOI: 10.1021/jm061327z] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [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
Our investigation of bivalent ligands at mu, delta, and kappa opioid receptors is focused on the preparation of ligands containing kappa agonist and mu agonist/antagonist pharmacophores at one end joined by a chain containing the mu antagonist pharmacophores (naltrexone, naloxone, or nalbuphine) at the other end. These ligands were evaluated in vitro by their binding affinity at mu, delta, and kappa opioid receptors and their relative efficacy in the [35S]GTPgammaS assay.
Collapse
MESH Headings
- 3,4-Dichloro-N-methyl-N-(2-(1-pyrrolidinyl)-cyclohexyl)-benzeneacetamide, (trans)-Isomer/pharmacology
- Animals
- CHO Cells
- Cricetinae
- Cricetulus
- Guanosine 5'-O-(3-Thiotriphosphate)/pharmacology
- Humans
- Ligands
- Morphinans/chemical synthesis
- Morphinans/chemistry
- Morphinans/pharmacology
- Nalbuphine/analogs & derivatives
- Nalbuphine/chemical synthesis
- Nalbuphine/pharmacology
- Naloxone/analogs & derivatives
- Naloxone/chemical synthesis
- Naloxone/pharmacology
- Naltrexone/analogs & derivatives
- Naltrexone/chemical synthesis
- Naltrexone/pharmacology
- Radioligand Assay
- Receptors, Opioid, delta/agonists
- Receptors, Opioid, delta/antagonists & inhibitors
- Receptors, Opioid, delta/drug effects
- Receptors, Opioid, kappa/agonists
- Receptors, Opioid, kappa/antagonists & inhibitors
- Receptors, Opioid, kappa/drug effects
- Receptors, Opioid, mu/agonists
- Receptors, Opioid, mu/antagonists & inhibitors
- Receptors, Opioid, mu/drug effects
- Structure-Activity Relationship
Collapse
Affiliation(s)
| | | | | | - John L. Neumeyer
- To whom correspondence should be addressed. Phone: 617-855-3388. Fax: 617-855-2519.
| |
Collapse
|
8
|
Hamad MO, Kiptoo PK, Stinchcomb AL, Crooks PA. Synthesis and hydrolytic behavior of two novel tripartate codrugs of naltrexone and 6beta-naltrexol with hydroxybupropion as potential alcohol abuse and smoking cessation agents. Bioorg Med Chem 2006; 14:7051-61. [PMID: 16798000 DOI: 10.1016/j.bmc.2006.06.018] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [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] [Received: 04/18/2006] [Revised: 06/07/2006] [Accepted: 06/08/2006] [Indexed: 12/01/2022]
Abstract
A codrug approach for simultaneous treatment of alcohol abuse and tobacco dependence is considered as very desirable because of substantial evidence that smoking is increased significantly during drinking, and that smoking is regarded as a behavioral 'cue' for the urge to consume alcohol. The purpose of this study was to design and synthesize codrugs for simultaneous treatment of alcohol abuse and tobacco dependence. Two novel tripartate codrugs of naltrexone (NTX) and naltrexol (NTXOL) covalently linked to hydroxybupropion (BUPOH) were synthesized (25 and 26, respectively), and their hydrolytic cleavage to the parent drugs was determined. These codrugs were generally less crystalline when compared to NTX, or NTXOL, as indicated by their lower melting points, and were expected to be more lipid-soluble. Also, the calculated clogP values were found to be higher for the codrugs compared to those for NTX and NTXOL. The studies on the hydrolysis of the codrugs provided good evidence that they could be efficiently converted to the parent drugs in buffer at physiological pH. Thus, these codrugs are likely to be cleaved enzymatically in vivo to generate the parent drugs, and are considered to be potential candidates for simultaneous treatment of alcohol abuse and tobacco dependence.
Collapse
Affiliation(s)
- Mohamed O Hamad
- College of Pharmacy, Department of Pharmaceutical Sciences, University of Kentucky, Lexington, KY 40536-0082, USA
| | | | | | | |
Collapse
|
9
|
Vaddi HK, Hamad MO, Chen J, Banks SL, Crooks PA, Stinchcomb AL. Human skin permeation of branched-chain 3-0-alkyl ester and carbonate prodrugs of naltrexone. Pharm Res 2005; 22:758-65. [PMID: 15906171 DOI: 10.1007/s11095-005-2592-9] [Citation(s) in RCA: 23] [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] [Received: 11/18/2004] [Accepted: 02/02/2005] [Indexed: 11/26/2022]
Abstract
PURPOSE Physicochemical characterization and in vitro human skin diffusion studies of branched-chain ester and carbonate prodrugs of naltrexone (NTX) were compared and contrasted with straight-chain ester and carbonate NTX prodrugs. METHODS Human skin permeation rates, thermal parameters, solubilities in mineral oil and buffer, and stabilities in buffer and plasma were determined. Partition coefficients between stratum corneum and vehicle were determined for straight- and branched-chain esters with the same number of carbon atoms. RESULTS Branched prodrugs had lower melting points, lower buffer solubilities, and higher mineral oil solubilities than NTX. The transdermal flux values from all of these branched prodrugs were significantly lower than flux values from the straight-chain ester and the methyl carbonate prodrugs. Straight-chain prodrugs had higher partition coefficient values and higher calculated thermodynamic activities than their branched-chain counterparts. The prodrug hydrolysis to NTX in buffer and plasma was slower for prodrugs with increased branching. CONCLUSIONS Branched-chain prodrugs with bulky moieties had smaller stratum corneum-vehicle partition coefficients and lower thermodynamic activities that resulted in smaller transdermal flux values than straight-chain prodrugs.
Collapse
Affiliation(s)
- Haranath K Vaddi
- Department of Pharmaceutical Sciences, University of Kentucky College of Pharmacy, Lexington, Kentucky, USA
| | | | | | | | | | | |
Collapse
|
10
|
Daniels DJ, Kulkarni A, Xie Z, Bhushan RG, Portoghese PS. A bivalent ligand (KDAN-18) containing delta-antagonist and kappa-agonist pharmacophores bridges delta2 and kappa1 opioid receptor phenotypes. J Med Chem 2005; 48:1713-6. [PMID: 15771416 DOI: 10.1021/jm034234f] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.5] [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: 11/30/2022]
Abstract
To characterize delta- and kappa-opioid receptor phenotypes, bivalent ligands (KDAN series) containing delta-antagonist (naltrindole) and kappa(1)-agonist (ICI-199,441) pharmacophores were synthesized and evaluated by the intrathecal route using the mouse tail-flick assay and binding studies. The data have suggested that KDAN-18 (2) bridges phenotypic delta(2)- and kappa(1)-receptors. A conceptual model is presented to explain the organizational differences between the opioid receptors that give rise to the phenotypes (delta(1), delta(2), kappa(1), kappa(2)).
Collapse
Affiliation(s)
- David J Daniels
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | | | | | | | | |
Collapse
|
11
|
Chauvignac C, Miller CN, Srivastava SK, Lewis JW, Husbands SM, Traynor JR. Major effect of pyrrolic N-benzylation in norbinaltorphimine, the selective kappa-opioid receptor antagonist. J Med Chem 2005; 48:1676-9. [PMID: 15743210 DOI: 10.1021/jm049172n] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [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
Indolic N-benzylation of naltrindole reportedly extends the duration of delta-opioid receptor (DOR) antagonism. Similar modification of the kappa-opioid receptor (KOR) antagonist norBNI (1a) and its 17,17'-diNMe analogue (1d), a low potency mu-opioid receptor (MOR) partial agonist, was found to affect predominantly their MOR activity. When administered systemically in mouse antinociceptive assays, N-benzyl-norBNI (1b) had only MOR agonist activity of relatively short duration whereas on central administration it had only a KOR-antagonist action of extremely long duration.
Collapse
Affiliation(s)
- Cédric Chauvignac
- Department of Pharmacy and Pharmacology, University of Bath, Bath BA2 7AY, UK
| | | | | | | | | | | |
Collapse
|
12
|
Shefali S, Srivastava SK, Husbands SM, Lewis JW. Extension of the Nenitzescu Reaction to Simple Ketones Provides an Efficient Route to 1‘-Alkyl-5‘-hydroxynaltrindole Analogues, Potent and Selective δ-Opioid Receptor Antagonists. J Med Chem 2004; 48:635-8. [PMID: 15658877 DOI: 10.1021/jm040853s] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [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
The well-established Nenitzescu reaction of imines of beta-dicarbonyl systems, as their enamine tautomers, with benzoquinone has been applied to a wide range of such imines to give 5-hydroxyindoles, some of which are of significant biological importance. This reaction has now been extended to the benzylimines of simple ketones, including those of the potent mu-opioid receptor antagonists naltrexone and naloxone. The products of the latter reactions, 1'-benzyl-5'-hydroxyindolomorphinans (7), are potent delta-opioid receptor (DOR) antagonists, confirming the enhancement of DOR antagonist potency and selectivity resulting from the introduction of the 1'-benzyl group.
Collapse
Affiliation(s)
- Shefali Shefali
- Department of Pharmacy and Pharmacology, University of Bath, Bath, BA2 7AY, UK
| | | | | | | |
Collapse
|
13
|
Srivastava SK, Shefali S, Miller CN, Aceto MD, Traynor JR, Lewis JW, Husbands SM. Effects of Substitution on the Pyrrole N Atom in Derivatives of Tetrahydronaltrindole, Tetrahydrooxymorphindole, and a Related 4,5-Epoxyphenylpyrrolomorphinan. J Med Chem 2004; 47:6645-8. [PMID: 15588100 DOI: 10.1021/jm040817t] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [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
The effect of substitution of the pyrrolo- and indolo-N atoms in tetrahydronaltrindole (TNTI), tetrahydrooxymorphindole (TOMI), and 17-cyclopropylmethyl-3,14-dihydroxy-4,5-epoxy-4'-phenyl-6,7:2',3'-pyrrolomorphinan (4) is reported. In opioid functional assays 4 were potent deltaopioid receptor (DOR) antagonists while the TNTI derivatives (7) were potent DOR antagonists or low-efficacy DOR partial agonists without substantial selectivity. The TOMI derivatives (8) were DOR agonists with significant selectivity. In vivo the DOR antagonist activity of 7d was confirmed, but the predominant agonist effect of 8d was shown to be mu opioid receptor mediated.
Collapse
MESH Headings
- Analgesics/chemical synthesis
- Analgesics/chemistry
- Analgesics/pharmacology
- Animals
- Binding, Competitive
- CHO Cells
- Cricetinae
- Cricetulus
- Humans
- Indoles/chemical synthesis
- Indoles/chemistry
- Indoles/pharmacology
- Ligands
- Morphinans/chemical synthesis
- Morphinans/chemistry
- Morphinans/pharmacology
- Naltrexone/analogs & derivatives
- Naltrexone/chemical synthesis
- Naltrexone/chemistry
- Naltrexone/pharmacology
- Radioligand Assay
- Receptors, Opioid, delta/agonists
- Receptors, Opioid, delta/antagonists & inhibitors
- Receptors, Opioid, kappa/agonists
- Receptors, Opioid, kappa/antagonists & inhibitors
- Receptors, Opioid, mu/agonists
- Receptors, Opioid, mu/antagonists & inhibitors
- Structure-Activity Relationship
Collapse
Affiliation(s)
- Sanjay K Srivastava
- Department of Pharmacy and Pharmacology, University of Bath, Bath, BA2 7AY, U.K
| | | | | | | | | | | | | |
Collapse
|
14
|
Bhushan RG, Sharma SK, Xie Z, Daniels DJ, Portoghese PS. A bivalent ligand (KDN-21) reveals spinal delta and kappa opioid receptors are organized as heterodimers that give rise to delta(1) and kappa(2) phenotypes. Selective targeting of delta-kappa heterodimers. J Med Chem 2004; 47:2969-72. [PMID: 15163177 DOI: 10.1021/jm0342358] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.0] [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: 12/22/2022]
Abstract
In view of recent pharmacological studies suggesting the existence of delta-kappa opioid receptor heterodimers/oligomers in the spinal cord, we have synthesized and evaluated (intrathecally in mice) a series of bivalent ligands (KDN series) containing kappa and delta antagonist pharmacophores. Pharmacological and binding data have provided evidence for the bridging of spinal delta-kappa receptor heterodimers by KDN-21 and for their identification as delta(1) and kappa(2). The selectivity profile of KDN-21 and the apparent absence of coupled delta(1)-kappa(2) phenotypes in the brain suggest a new approach for targeting receptors.
Collapse
Affiliation(s)
- Rashmi G Bhushan
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis, MN 55455, USA
| | | | | | | | | |
Collapse
|
15
|
Hammell DC, Hamad M, Vaddi HK, Crooks PA, Stinchcomb AL. A duplex “Gemini” prodrug of naltrexone for transdermal delivery. J Control Release 2004; 97:283-90. [PMID: 15196755 DOI: 10.1016/j.jconrel.2004.03.020] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [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] [Received: 12/31/2003] [Accepted: 03/17/2004] [Indexed: 10/26/2022]
Abstract
Transdermal naltrexone delivery is desirable in the treatment of narcotic dependence and alcoholism. The purpose of this study was to increase the delivery rate of naltrexone (NTX) across human skin by using a novel prodrug. A duplex "gemini" prodrug of naltrexone was synthesized and evaluated. In vitro human skin permeation rates of naltrexone and prodrug were measured using a flow-through diffusion cell system. Drug concentrations in the skin were quantitated at the end of the diffusion experiment. The prodrug was hydrolyzed on passing through the skin and appeared mainly as naltrexone in the receiver compartment. The prodrug provided a significantly higher naltrexone equivalent flux across human skin in vitro than naltrexone base. The naltrexone equivalent solubilities of naltrexone and the prodrug in the donor solution were not significantly different. No significant increase in drug concentration in the skin after prodrug treatment, as compared to naltrexone, was observed. The naltrexone equivalent permeability from the prodrug exceeded the permeability of naltrexone base by two-fold. Due to the design of this prodrug, toxicities associated with this compound should be nonexistent, because only naltrexone and carbon dioxide (carbonic acid) are released when the prodrug is cleaved.
Collapse
Affiliation(s)
- Dana C Hammell
- Division of Pharmaceutical Sciences, University of Kentucky College of Pharmacy, 900 Rose St., Lexington, KY 40536-0082, USA
| | | | | | | | | |
Collapse
|
16
|
Suhaida MG, Yahya IB, Darmawati MY. Preparation of naltrexone hydrochloride loaded poly (DL-lactide-co-glycolide) microspheres and the effect of polyvinyl alcohol (PVA) as surfactant on the characteristics of the microspheres. Med J Malaysia 2004; 59 Suppl B:63-4. [PMID: 15468820] [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: 04/30/2023]
Abstract
The aim of this study was to investigate the effect of the surfactant properties of polyvinyl alcohol (PVA) in enhancing the yield of small size microspheres. Naltrexone microspheres were prepared by solvent-solvent extraction evaporation process. PVA of various concentrations were added into the aqueous phase prior to the mixing process. The addition of PVA was expected to influence the shape, size distribution, drug loading and drug release profile. The results indicated that it is desirable to increase the weight fraction of the microspheres with size range below 106 mm for the highest possible yield.
Collapse
|
17
|
Tanaka H, Ohno H, Kawamura K, Ohtake A, Nagase H, Takahashi T. Solid-phase synthesis of naltrindole derivatives using Fischer indole synthesis based on one-pot release and cyclization methodology. Org Lett 2003; 5:1159-62. [PMID: 12688708 DOI: 10.1021/ol020230d] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [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: 11/28/2022]
Abstract
[reaction: see text] We describe a new approach for the solid-phase synthesis of indoles 1 that involves a one-pot release and cyclization reaction of a solid-supported hydrazone through a Wang-type linker. Using this solid-phase methodology, we accomplished the synthesis of 40 naltrindole derivatives.
Collapse
Affiliation(s)
- Hiroshi Tanaka
- Department of Applied Chemistry, Tokyo Institute of Technology, Meguro, Tokyo 152-8552, Japan
| | | | | | | | | | | |
Collapse
|
18
|
Ananthan S, Kezar HS, Saini SK, Khare NK, Davis P, Dersch CM, Porreca F, Rothman RB. Synthesis, opioid receptor binding, and functional activity of 5'-substituted 17-cyclopropylmethylpyrido[2',3':6,7]morphinans. Bioorg Med Chem Lett 2003; 13:529-32. [PMID: 12565965 DOI: 10.1016/s0960-894x(02)00934-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [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: 11/20/2022]
Abstract
A series of naltrexone-derived pyridomorphinans possessing various substituents at the 5'-position on the pyridine ring were synthesized and evaluated for opioid receptor binding in rodent brain membranes and functional activity in smooth muscle preparations. While the introduction of aromatic 1-pyrrolyl group (6h) improved the delta affinity and delta antagonist potency of the parent compound (3), the introduction of guanidine group (6i) transformed it to a kappa selective ligand in opioid receptor binding and [35S]GTP-gamma-S functional assays.
Collapse
MESH Headings
- Animals
- Brain Chemistry/drug effects
- Guanidines/chemical synthesis
- Guanidines/pharmacology
- Guanosine 5'-O-(3-Thiotriphosphate)/metabolism
- Guinea Pigs
- Ileum/drug effects
- In Vitro Techniques
- Indicators and Reagents
- Male
- Morphinans/chemical synthesis
- Morphinans/pharmacology
- Muscle Contraction/drug effects
- Muscle, Smooth/drug effects
- Muscle, Smooth/metabolism
- Naltrexone/analogs & derivatives
- Naltrexone/chemical synthesis
- Naltrexone/pharmacology
- Narcotic Antagonists/chemical synthesis
- Narcotic Antagonists/pharmacology
- Pyridines/chemical synthesis
- Pyridines/pharmacology
- Rats
- Receptors, Opioid/drug effects
- Receptors, Opioid/metabolism
- Receptors, Opioid, delta/antagonists & inhibitors
- Receptors, Opioid, delta/drug effects
- Receptors, Opioid, delta/metabolism
- Receptors, Opioid, kappa/antagonists & inhibitors
- Receptors, Opioid, kappa/drug effects
- Receptors, Opioid, kappa/metabolism
- Receptors, Opioid, mu/drug effects
- Receptors, Opioid, mu/metabolism
- Structure-Activity Relationship
- Vas Deferens/drug effects
Collapse
Affiliation(s)
- Subramaniam Ananthan
- Organic Chemistry Department, Southern Research Institute, Birmingham, AL 35255, USA.
| | | | | | | | | | | | | | | |
Collapse
|
19
|
Black SL, Jales AR, Brandt W, Lewis JW, Husbands SM. The role of the side chain in determining relative delta- and kappa-affinity in C5'-substituted analogues of naltrindole. J Med Chem 2003; 46:314-7. [PMID: 12519069 DOI: 10.1021/jm020997b] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [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
The role of the side chain in 5'-substituted analogues of naltrindole has been further explored with the synthesis of series of amides, amidines, and ureas. Amidines (8, 13) had greatest selectivity for the kappa receptor, as predicted from consideration of the message-address concept. It was also found that an appropriately located carbonyl group, in ureas (10) and amides (7), led to retention of affinity and antagonist potency at the delta receptor.
Collapse
Affiliation(s)
- Shannon L Black
- Department of Pharmacy and Pharmacology, University of Bath, Bath, BA2 7AY, UK
| | | | | | | | | |
Collapse
|
20
|
Wentland MP, Lou R, Dehnhardt CM, Duan W, Cohen DJ, Bidlack JM. 3-Carboxamido analogues of morphine and naltrexone. synthesis and opioid receptor binding properties. Bioorg Med Chem Lett 2001; 11:1717-21. [PMID: 11425545 DOI: 10.1016/s0960-894x(01)00278-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [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: 10/27/2022]
Abstract
In response to the unexpectedly high affinity for opioid receptors observed in a novel series of cyclazocine analogues where the prototypic 8-OH was replaced by a carboxamido group, we have prepared the corresponding 3-CONH(2) analogues of morphine and naltrexone. High affinity (K(i)=34 and 1.7nM) for mu opioid receptors was seen, however, the new targets were 39- and 11-fold less potent than morphine and naltrexone, respectively.
Collapse
Affiliation(s)
- M P Wentland
- Department of Chemistry, Rensselaer Polytechnic Institute, 110 8th Street, 12180, Troy, NY, USA.
| | | | | | | | | | | |
Collapse
|
21
|
Le Bourdonnec B, El Kouhen R, Poda G, Law PY, Loh HH, Ferguson DM, Portoghese PS. Covalently induced activation of the delta opioid receptor by a fluorogenic affinity label, 7'-(phthalaldehydecarboxamido)naltrindole (PNTI). J Med Chem 2001; 44:1017-20. [PMID: 11297446 DOI: 10.1021/jm010004u] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- B Le Bourdonnec
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | | | | | | | | | | | | |
Collapse
|
22
|
Jales AR, Husbands SM, Lewis JW. Selective kappa-opioid antagonists related to naltrindole. Effect of side-chain spacer in the 5'-amidinoalkyl series. Bioorg Med Chem Lett 2000; 10:2259-61. [PMID: 11055333 DOI: 10.1016/s0960-894x(00)00433-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [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: 11/21/2022]
Abstract
The study of kappa-opioid receptor function in vivo has been hampered by the limited choice of selective kappa-antagonists. Recently discovered kappa-antagonists have not yet been utilised in vivo. We here report the synthesis and in vitro evaluation of a new amidine derivative of naltrindole. It showed substantially greater kappa-selectivity in binding assays than known analogues with shorter spacer in the amidine side chain. This indicates that in nor-BNI and related selective kappa-antagonists, the second basic centre may not be ideally located.
Collapse
Affiliation(s)
- A R Jales
- School of Chemistry, University of Bristol, UK
| | | | | |
Collapse
|
23
|
Le Bourdonnec B, El Kouhen R, Lunzer MM, Law PY, Loh HH, Portoghese PS. Reporter affinity labels: an o-phthalaldehyde derivative of beta-naltrexamine as a fluorogenic ligand for opioid receptors. J Med Chem 2000; 43:2489-92. [PMID: 10891107 DOI: 10.1021/jm000138s] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- B Le Bourdonnec
- Department of Medicinal Chemistry, College of Pharmacy, School of Medicine, University of Minnesota, Minneapolis 55455, USA
| | | | | | | | | | | |
Collapse
|
24
|
Abstract
[formula: see text] The phenolic hydroxy group of opiate-derived ligands is of known importance for biological activity. On the basis of its putative role as a hydrogen-bonding donor in the interaction with opioid receptors, it was replaced with a sulfonamide group because of their similar pKa values. The first thebaine-derived 3-amino (8a, 8b) and subsequent sulfonamide analogues (10a, 10b) were synthesized from naltrexone (1a) and oxymorphone (1b) in a linear nine-step synthesis. The sulfonamides were tested in vitro and found inactive.
Collapse
Affiliation(s)
- C R McCurdy
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis 55455, USA
| | | | | |
Collapse
|
25
|
Coop A, Rothman RB, Dersch C, Partilla J, Porreca F, Davis P, Jacobson AE, Rice KC. delta Opioid affinity and selectivity of 4-hydroxy-3-methoxyindolomorphinan analogues related to naltrindole. J Med Chem 1999; 42:1673-9. [PMID: 10229636 DOI: 10.1021/jm9807003] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [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: 11/30/2022]
Abstract
To investigate the effect of the introduction of a 4-phenolic substituent on the delta opioid affinity and selectivity of the indolomorphinans, a range of 4-phenolic analogues of naltrindole were prepared and evaluated in in vitro assays. Although the majority of the ligands displayed poor affinity for all three opioid receptors (mu, kappa, delta), 17-cyclopropylmethyl-6, 7-didehydro-4-hydroxy-3-methoxy-6,7:2',3'-indolomorphinan (13) was an exception, displaying excellent delta binding selectivity (delta Ki = 7 nM, mu/delta = 1900, mu/kappa = 1130). GTP-gamma-S functional assays showed 13 to be a selective delta antagonist, albeit with lower potency than naltrindole. Although the reason for the unique profile of 13 could not be determined, these results validate our approach of introducing groups into the indolomorphinans that are known to reduce mu activity, to obtain increased delta selectivity.
Collapse
Affiliation(s)
- A Coop
- Laboratory of Medicinal Chemistry, Building 8, Room B1-23, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | | | | | | | | | | | | | | |
Collapse
|
26
|
Jones RM, Hjorth SA, Schwartz TW, Portoghese PS. Mutational evidence for a common kappa antagonist binding pocket in the wild-type kappa and mutant mu[K303E] opioid receptors. J Med Chem 1998; 41:4911-4. [PMID: 9836606 DOI: 10.1021/jm9805182] [Citation(s) in RCA: 66] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
MESH Headings
- Amino Acid Sequence
- Animals
- Binding, Competitive
- COS Cells
- Guanidines
- Guinea Pigs
- Ileum/drug effects
- In Vitro Techniques
- Male
- Mice
- Models, Molecular
- Molecular Conformation
- Molecular Sequence Data
- Morphinans
- Muscle, Smooth/drug effects
- Mutation
- Naltrexone/analogs & derivatives
- Naltrexone/chemical synthesis
- Naltrexone/metabolism
- Naltrexone/pharmacology
- Narcotic Antagonists/chemical synthesis
- Narcotic Antagonists/metabolism
- Narcotic Antagonists/pharmacology
- Rats
- Receptors, Opioid, kappa/antagonists & inhibitors
- Receptors, Opioid, kappa/metabolism
- Receptors, Opioid, mu/genetics
- Receptors, Opioid, mu/metabolism
- Vas Deferens/drug effects
Collapse
Affiliation(s)
- R M Jones
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | | | | | | |
Collapse
|
27
|
Abstract
A series of 7-arylidinenaltrexones (2a-m) related to the prototypical delta1-selective antagonist, 7-benzylidenenaltrexone 1 (BNTX), have been synthesized in an effort to develop more selective ligands. Testing in smooth muscle preparations revealed that members of the series exhibited varying degrees of selectively for delta receptors, with the o-methoxy (2e) and o-chloro (2j) congeners being most potent and most selective (Ke approximately 0.8 nm). Evaluation of 1, 2e, and 2f sc in mice using the tail-flick procedure indicated that they are selective delta1 opioid receptor antagonists in the lower dose range. At high doses these ligands, including BNTX, exhibited decreased delta1 selectivity due to increases in the ED50 ratios of [D-Ser2,Leu5]enkephalin-Thr6 and morphine. It is concluded that 2e and 2f possess in vivo selectivity similar to that of BNTX, but are less potent as delta1 antagonists.
Collapse
Affiliation(s)
- S Ohkawa
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | | |
Collapse
|
28
|
Kubota H, Rothman RB, Dersch C, McCullough K, Pinto J, Rice KC. Synthesis and biological activity of 3-substituted 3-desoxynaltrindole derivatives. Bioorg Med Chem Lett 1998; 8:799-804. [PMID: 9871544 DOI: 10.1016/s0960-894x(98)00105-x] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [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: 10/27/2022]
Abstract
The 3-unsubstituted and substituted analogs of naltrindole (NTI) were synthesized using palladium-catalyzed transformations, and their binding affinity to opioid receptors was determined. Although the 3-desoxy analog showed comparable delta selectivity with that of NTI, all of the novel compounds possessed low affinity for delta receptors indicating the important role of the 3-oxygen atom of NTI for interaction with delta-opioid receptors.
Collapse
Affiliation(s)
- H Kubota
- Laboratory of Medicinal Chemistry, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892, USA
| | | | | | | | | | | |
Collapse
|
29
|
Fang X, Larson DL, Portoghese PS. 7-spirobenzocyclohexyl derivatives of naltrexone, oxymorphone, and hydromorphone as selective opioid receptor ligands. J Med Chem 1997; 40:3064-70. [PMID: 9301669 DOI: 10.1021/jm970283e] [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: 02/05/2023]
Abstract
On the basis of previous structure-activity studies of the highly potent and selective delta-opioid receptor antagonist naltrindole (1) and the spiroindanyl analogues 2 and 3, we have synthesized epimeric pairs of spirobenzocyclohexyl derivatives of naltrexone, oxymorphone, and hydromorphone (4-9). Pharmacologic evaluation in smooth muscle assays has revealed that the oxymorphone derivatives (6, 7) are delta-selective agonists and possess receptor binding profiles that are consistent with their agonist activity. It is proposed that the spirobenzocyclohexyl group of 6 and 7 orients its benzene moiety orthogonally with respect to the C ring of the opiate in a manner similar to that of the spiroindanyl analogue 3. It is suggested that this orthogonal orientation serves as an "address" to facilitate activation of delta receptors. The finding that the hydromorphone analogues (8, 9) were full mu agonists and exhibited only partial delta agonist activity suggests that the 14-hydroxyl group also contributes to the delta agonist activity. The naltrexone derivatives (4, 5) were mu-selective antagonists and exhibited relatively weak delta antagonist activity. However, the binding data indicated a very high-affinity delta-selective binding profile that was not consistent with the pharmacology. This study illustrates the differential contributions of the delta "address" to agonist and antagonist activity and supports the idea of different recognition sites for interaction of agonist and antagonist ligands with delta-opioid receptors.
Collapse
Affiliation(s)
- X Fang
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis 55455, USA
| | | | | |
Collapse
|
30
|
Ohkawa S, DiGiacomo B, Larson DL, Takemori AE, Portoghese PS. 7-Spiroindanyl derivatives of naltrexone and oxymorphone as selective ligands for delta opioid receptors. J Med Chem 1997; 40:1720-5. [PMID: 9171881 DOI: 10.1021/jm9700880] [Citation(s) in RCA: 14] [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: 02/04/2023]
Abstract
A series consisting of spiroindanyl (5-7), benzospiroindanyl (8-10), and spiroperinaphthyl (11) derivatives of naltrexone and oxymorphone were synthesized in order to investigate the role of an orthogonal-oriented "address" for delta opioid receptors. All of the ligands exhibited a preference for delta receptors in vitro. The 7-benzospiroindanyl derivative 8 (BSINTX) was the most selective delta opioid receptor antagonist in vitro. In mice BSINTX antagonized the delta 1-selective agonist, [D-Pen2,D-Pen5]enkephalin without significantly affecting the antinociceptive potency of delta 2, mu, and kappa agonists. The results of this study are consistent with an orthogonally-oriented address favoring delta 1 activity.
Collapse
MESH Headings
- Analgesia
- Analgesics
- Animals
- Brain/metabolism
- Cell Membrane/metabolism
- Enkephalin, D-Penicillamine (2,5)-
- Enkephalins/antagonists & inhibitors
- Enkephalins/metabolism
- Guinea Pigs
- Ileum
- Ligands
- Male
- Mice
- Mice, Inbred ICR
- Molecular Structure
- Muscle, Smooth/drug effects
- Muscle, Smooth/physiology
- Naltrexone/analogs & derivatives
- Naltrexone/chemical synthesis
- Naltrexone/metabolism
- Naltrexone/pharmacology
- Oxymorphone/analogs & derivatives
- Receptors, Opioid, delta/agonists
- Receptors, Opioid, delta/antagonists & inhibitors
- Receptors, Opioid, delta/metabolism
- Spiro Compounds/chemical synthesis
- Spiro Compounds/metabolism
- Spiro Compounds/pharmacology
- Vas Deferens
Collapse
Affiliation(s)
- S Ohkawa
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis 55455, USA
| | | | | | | | | |
Collapse
|
31
|
Abstract
The E-isomer of 7-benzylidenenaltrexone (BNTX, la) was reported by Portoghese as a highly selective delta-opioid antagonist. The corresponding Z-isomer 1b was not readily available through direct aldol condensation of naltrexone (6) with benzaldehyde. Using the photochemical methods employed by Lewis to isomerize cinnamamides, we have obtained Z-isomer 1b in good yield from E-isomer 1a. A series of (E)- and (Z)-7-arylidenenaltrexone derivatives was prepared to study the effect of larger arylidene groups on opioid receptor affinity in this series. By aldol condensation of naltrexone (6) with benzaldehyde, 1-naphthaldehyde, 2-naphthaldehyde, 4-phenylbenzaldehyde, and 9-anthracaldehyde, the (E)-arylidenes were readily obtained. Photochemical isomerization afforded the corresponding Z-isomers. These compounds were evaluated via opioid receptor radioligand displacement assays. In these assays, the Z-isomers generally had higher affinity and were more delta-selective than the corresponding E-isomers. The (Z)-7-(1-naphthylidene)naltrexone (3b) showed the greatest selectivity (delta:mu ratio of 15) and highest affinity delta-binding (Ki = 0.7 nM). PM3 semiempirical geometry optimizations suggest a significant role for the orientation of the arylidene substituent in the binding affinity and delta-receptor selectivity. This work demonstrates that larger groups may be incorporated into the arylidene portion of the molecule with opioid receptor affinity being retained.
Collapse
Affiliation(s)
- R B Palmer
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle 98195, USA
| | | | | |
Collapse
|
32
|
Abstract
Cinnamoyl derivatives of beta-naltrexamine (beta-NTA) have been prepared and evaluated as potential irreversible opioid antagonists. In receptor binding assays, isolated tissue preparations and mouse antinociception assays the p-methylcinnamoyl derivative BU42 was similar to the standard opioid ligand beta-funaltrexamine (beta-FNA). The main features were reversible kappa agonism and irreversible mu antagonism. Surprisingly the p-chlorocinnamoyl derivative BU59 showed only modest competitive antagonist activity in-vivo despite appearing to bind irreversibly to mu receptors in the guinea-pig ileum (GPI) preparation. BU60, the dihydrocinnamoyl analogue of BU59, like BU59 displayed reversible kappa agonism in GPI but in mouse antinociception assays its agonism was mediated by mu and delta receptors rather than kappa. The surprising changes of profile attributable to substitution in the aromatic ring of the cinnamoylamido group in this small series suggests that a larger range of substituted cinnamoylamido derivatives should be studied to further elucidate the effects of Michael acceptor activity and other factors.
Collapse
Affiliation(s)
- I Derrick
- School of Chemistry, University of Bristol, UK
| | | | | | | | | |
Collapse
|
33
|
Abstract
Analogues of naltrindole and N1'-methylnaltrindole having radioiodine in the 7'-position of the indole ring have been prepared for evaluation as delta opioid receptor ligands. The no-carrier-added radiosyntheses were conducted by Cu(I) assisted nucleophilic exchange of radioiodide for bromide under reducing conditions at 190 degrees C. A combination of HPLC and solid-phase extraction gave the 125I- or 123I-labeled products in satisfactory yields (47%) with high radiochemical purities (> 98%) and high specific activities (125I: 43-68 GBq/mumol, 1155-1833 mCi/mumol; 123I: > 92 GBq/mumol, 2500 mCi/mumol).
Collapse
Affiliation(s)
- C M Kinter
- Department of Environmental Health Sciences, Johns Hopkins University School of Hygiene and Public Health, Baltimore, MD 21205-2179, USA
| | | |
Collapse
|
34
|
Portoghese PS, Ohkawa S, Moe ST, Takemori AE. Synthesis and delta-opioid receptor antagonist activity of a naltrindole analogue with a regioisomeric indole moiety. J Med Chem 1994; 37:1886-8. [PMID: 8021929 DOI: 10.1021/jm00038a019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [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: 01/28/2023]
Abstract
Indolomorphinans 2 and 3, in which the indole moiety is fused to the 7,8-position of the morphinan system, have been synthesized from dihydropseudocodeinone 4 and evaluated for antagonist activity on the mouse vas deferens (MVD) and guinea pig ileum (GPI) preparations. Indolomorphinan 2 was found to be approximately 1/60th as potent as naltrindole 1 in the MVD and an agonist in the GPI preparation. A comparable difference in affinity between 1 and 2 was observed. The methyl analogue 3 was inactive in both preparations. The results of this study support the idea that the regio orientation of the indolic benzene moiety of 1 is optimal for delta-opioid receptor antagonist activity. It is proposed that the proper alignment of the benzene moiety with an address subsite on the delta receptor is critical for potent delta antagonist activity.
Collapse
Affiliation(s)
- P S Portoghese
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis 55455
| | | | | | | |
Collapse
|
35
|
Portoghese PS, Lin CE, Farouz-Grant F, Takemori AE. Structure-activity relationship of N17'-substituted norbinaltorphimine congeners. Role of the N17' basic group in the interaction with a putative address subsite on the kappa opioid receptor. J Med Chem 1994; 37:1495-500. [PMID: 8182708 DOI: 10.1021/jm00036a015] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.0] [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: 01/29/2023]
Abstract
A series of norbinaltorphimine congeners (2-12) which contain different groups at the N17'-position have been synthesized in order to evaluate the role of N17' in conferring kappa opioid antagonist selectivity at opioid receptor sites. The compounds that contain a basic N17' nitrogen (2-9) were found to be selective kappa antagonists. Amidation of N17' afforded congeners 10-12 with feeble kappa antagonist potency and low selectivity. The fact that potent antagonism and selectivity were observed only when members of the series contain a basic N17' nitrogen suggests that it interacts with extracellular domains of the kappa receptor that contain acidic amino acid residues. The N-terminal domain and extracellular loop 2, both of which contain acidic residues, are candidates for this interaction and may be components of the kappa address subsite of the receptor.
Collapse
Affiliation(s)
- P S Portoghese
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis 55455
| | | | | | | |
Collapse
|
36
|
Portoghese PS, Sultana M, Moe ST, Takemori AE. Synthesis of naltrexone-derived delta-opioid antagonists. Role of conformation of the delta address moiety. J Med Chem 1994; 37:579-85. [PMID: 8126697 DOI: 10.1021/jm00031a006] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [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: 01/28/2023]
Abstract
Naltrindole (1) (NTI) is a highly potent and selective delta-opioid receptor antagonist. In an effort to understand the origin of the high potency, affinity, and selectivity of NTI, we have examined the conformational role of its indolic benzene moiety through the synthesis of related naltrexone derivatives 3-8, which contain the benzene moiety in different orientations and at different attachments in the molecule. One of these naltrexone derivatives, 5, whose 7-indanyl benzene moiety is orthogonal to ring C of the morphinan system, is a potent delta-opioid receptor antagonist in vitro and in vivo. Computer-assisted molecular overlay studies of the minimized structures (2-8) revealed the importance of the position of the benzene moiety for effective interaction with delta-opioid receptors. In compounds 2, 4, and 5, the aromatic ring falls in the same region of space as that of the indolic benzene moiety of NTI, and all of these ligands possessed significant activity at delta-opioid receptors. Analogues (3 and 6-8) which were shown to have relatively weak delta-opioid receptor antagonist potency have their aromatic groups located in a space that is different from that of the more potent analogues.
Collapse
Affiliation(s)
- P S Portoghese
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis 55455
| | | | | | | |
Collapse
|
37
|
Portoghese PS. The design of delta-selective opioid receptor antagonists. Farmaco 1993; 48:243-51. [PMID: 8388215] [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: 01/30/2023]
Abstract
Naltrexone-derived antagonists which are highly selective for delta opioid receptors have been designed using the message-address concept. The prototypical member of this series, naltrindole 1, possesses very high affinity and selectivity for delta receptors, and a closely related benzofuran analogue, NTB 2, is a selective delta 2 antagonist. The fact that 7-benzylidenenaltrexone (BNTX) was found to be a delta 1 antagonist suggests that the conformation of the putative delta address component (phenyl group) of BNTX plays a role in modulating delta subtype selectivity.
Collapse
Affiliation(s)
- P S Portoghese
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis 55455
| |
Collapse
|
38
|
Portoghese PS, Sultana M, Nelson WL, Klein P, Takemori AE. Delta opioid antagonist activity and binding studies of regioisomeric isothiocyanate derivatives of naltrindole: evidence for delta receptor subtypes. J Med Chem 1992; 35:4086-91. [PMID: 1331455 DOI: 10.1021/jm00100a014] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [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: 12/26/2022]
Abstract
The isothiocyanate group was attached to the 4'-, 5'-, 6'-, or 7'-position of naltrindole in an effort to determine the importance of the position of this electrophilic group on the selectivity for subtypes of delta opioid receptors. All of the ligands were delta-selective when tested against standard agonists in smooth muscle preparations. However, the rank-order delta antagonism of antinociception in mice did not parallel the in vitro pharmacologic data. The 5'-isothiocyanate 2 was the most potent and selective antagonist in vivo, causing a 52-fold increase of the ED50 for [D-Ser2,D-Leu5]enkephalin-Thr6 (DSLET) and no increase for [D-Pen2,D-Pen5]enkephalin (DPDPE). The effect of each of the ligands on the binding of [3H]DSLET and [3H]DPDPE to guinea pig brain membranes clearly differentiated between the binding sites that recognize these radioligands. These studies provide additional evidence for the presence of two subtypes of delta opioid receptors.
Collapse
Affiliation(s)
- P S Portoghese
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis 55455
| | | | | | | | | |
Collapse
|
39
|
Portoghese PS, Garzon-Aburbeh A, Nagase H, Lin CE, Takemori AE. Role of the spacer in conferring kappa opioid receptor selectivity to bivalent ligands related to norbinaltorphimine. J Med Chem 1991; 34:1292-6. [PMID: 1849995 DOI: 10.1021/jm00108a008] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.5] [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: 12/29/2022]
Abstract
The thiophene 2 and pyran 3 analogues of the kappa-selective opioid antagonist norbinaltorphimine (1a, norBNI) were synthesized and tested in an effort to determine the contribution of the spacer to the interaction of bivalent ligands at different opioid receptor types. Both 2 and 3 were found to be selective kappa opioid receptor antagonists in smooth muscle preparations, and they bound selectively to kappa-recognition sites. The thiophene analogue 2 displayed binding selectivity that was of the same order of magnitude as that of 1a, while 3 was considerably less selective for kappa site. This is consistent with the fact that the second pharmacophore in 1a and 2 displayed a greater degree of superposition than 1a and 3. The results of this study suggest that the pyrrole moiety of norBNI functions primarily as an inert spacer to rigidly hold the basic nitrogen in the second pharmacophore at an "address" subsite that is unique for the kappa opioid receptor.
Collapse
Affiliation(s)
- P S Portoghese
- Department of Medicinal Chemistry, College of Pharmacy, University of Minnesota, Minneapolis 55455
| | | | | | | | | |
Collapse
|
40
|
Olsen LD, Klein P, Nelson WL, Yao YH, Simon EJ. Conjugate addition ligands of opioid antagonists. Methacrylate esters and ethers of 6 alpha- and 6 beta-naltrexol. J Med Chem 1990; 33:737-41. [PMID: 2153826 DOI: 10.1021/jm00164a043] [Citation(s) in RCA: 3] [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: 12/30/2022]
Abstract
Alpha- and beta-naltrexol derived esters 9 and 10 and ethers 11 and 12, each containing the alpha, beta-unsaturated ester functionality, were prepared as conformationally more flexible analogues of spiro-alpha-methylene-gamma-lactones 5 and 6. All were active in the opioid radioreceptor binding assay against [3H]bremazocine and more active against [3H]DAGO, indicating mu-subtype selectivity, but only ether 12 showed significant irreversible activity. We conclude that small structural changes, made in very closely related electrophilic opioids, lead to changes in receptor binding. All four compounds were long-acting antagonists to morphine in mice, with ester 10 being approximately equipotent with naltrexone.
Collapse
Affiliation(s)
- L D Olsen
- Department of Medicinal Chemistry, School of Pharmacy, University of Washington, Seattle 98195
| | | | | | | | | |
Collapse
|
41
|
Abstract
Naltrexone-3-salicylate (3), a prodrug of naltrexone (1), was prepared by a simple procedure from naltrexone-3-acetylsalicylate (2). The plasma (dog and human) hydrolysis half-life of 3 was found to be approximately 30 min. Compound 2 was previously shown to hydrolyze in dog and human plasma with a fast deacetylation step to 3, followed by slower hydrolysis of 3 to 1 (t1/2, approximately 30 min). Oral naltrexone bioavailability was greatly improved (approximately 30-fold) after oral administration of 3 to dogs, similar to the improvement observed after oral administration of 2. The half-life of naltrexone in dogs after oral administration of 3 was similar to that observed after oral administration of 2 (approximately 1 hr).
Collapse
Affiliation(s)
- M A Hussain
- E. I. du Pont de Nemours & Company, Inc., Medical Products Department, Wilmington, Delaware 19898
| | | |
Collapse
|
42
|
Abstract
Previous studies from our laboratories have reported the synthesis and pharmacological characteristics of a series of symmetrical opiate azines: naloxonazine, oxymorphonazine and naltrexonazine. We have now synthesized and characterized in binding assays and in vivo two asymmetrical azines: oxymorphone-naltrexonazine and oxymorphone-3-methoxynaltrexonazine. Oxymorphone-naltrexonazine, which theoretically could interact with the receptor as either an agonist or antagonist, displayed antagonist properties in vitro and in vivo. Oxymorphone-3-methoxynaltrexonazine, which theoretically could bind only as an agonist, possessed agonist properties in binding studies and was a potent analgesic in vivo.
Collapse
|
43
|
Urbanczyk-Lipkowska Z, Lipkowski AW, Etter MC, Hahn EF, Pasternak GW, Portoghese PS. X-ray crystal structure of the opioid ligand naltrexonazine. J Med Chem 1987; 30:1489-94. [PMID: 3039139 DOI: 10.1021/jm00391a035] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [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
The anti-anti isomer of naltrexonazine (1) was synthesized, and its configuration was confirmed by X-ray crystallography. The syn-anti isomer is readily converted to 1 under acidic conditions. The apparent equal receptor binding of 1 and syn-anti isomer indicates that isomerization of the azine moiety may take place under the conditions of biological evaluation. Two possible explanations for wash-resistant binding of 1 to opioid receptors are presented. The first possibility involves a noncovalent interaction of the ligand with the opioid receptor, and the second considers covalent binding by a receptor-based sulfhydryl group.
Collapse
|
44
|
Schoenecker JW, Takemori AE, Portoghese PS. Opioid agonist and antagonist activities of monofunctional nitrogen mustard analogues of beta-chlornaltrexamine. J Med Chem 1987; 30:933-5. [PMID: 3033246 DOI: 10.1021/jm00388a033] [Citation(s) in RCA: 8] [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: 01/03/2023]
Abstract
In an effort to compare the role of a monofunctional nitrogen mustard with that of its bifunctional counterpart (i.e., beta-CNA, 1b) in modulating nonequilibrium activity of opioid receptors, we have synthesized and tested N-(2-chloroethyl)-N-methylamino analogues 2a and 2b. Compound 2b and beta-CNA (1b) possessed qualitatively similar pharmacologic profiles on the guinea pig ileum (GPI) and mouse vas deferens (MVD) preparations. Moreover, the corresponding epimer 2a behaved somewhat like that reported for alpha-CNA (1a) in that it possessed irreversible agonist activity in the GPI. The similar pharmacologic profiles of the monofunctional and bifunctional nitrogen mustards suggest that possible cross-linking of receptor nucleophiles by the latter is not critical for activity. In addition, the results are consistent with the idea that the rank-order nonequilibrium activity of 2b at different opioid receptor types is related to its relative affinity at those sites rather than to the alkylation step.
Collapse
|
45
|
Portoghese PS, Rein MD, Takemori AE. Synthesis and biological activity of analogues of beta-chlornaltrexamine and beta-funaltrexamine at opioid receptors. J Med Chem 1986; 29:1861-4. [PMID: 3020245 DOI: 10.1021/jm00160a011] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
beta-Chlornaltrexamine and beta-funaltrexamine analogues 4-7 with different length "arms" to which an electrophilic moiety is attached were synthesized in an effort to obtain affinity labels that would selectively and irreversibly block specific opioid receptor types and subtypes. One of the compounds, 4, was a potent, irreversible blocker of opioid receptors in the guinea pig ileum and mouse vas deferens preparations. The results of this study suggest that nucleophiles that are remote from the recognition locus are capable of alkylation by reactive electrophiles.
Collapse
|
46
|
Abstract
The N-methyl analogues (2a, 2b) of the nonequilibrium mu opioid receptor antagonist beta-funaltrexamine (1b) were synthesized and evaluated in the guinea pig ileum preparation (GPI). These analogues are highly potent, reversible opioid agonists and possess no nonequilibrium antagonist activity. The ineffectiveness of 2b in protecting against irreversible blockage of mu opioid receptors by 1b and the fivefold lower reactivity of 2b with cysteine suggest that N-methyl substitution adversely affects both the first and second recognition steps that are essential for effective covalent blockage of opioid receptors.
Collapse
|
47
|
Channing MA, Eckelman WC, Bennett JM, Burke TR, Rice KC. Radiosynthesis of [18F]3-acetylcyclofoxy: a high affinity opiate antagonist. Int J Appl Radiat Isot 1985; 36:429-33. [PMID: 2993171 DOI: 10.1016/0020-708x(85)90204-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
A convenient method for the preparation of high specific activity [18F]3-acetylcyclofoxy (3-acetyl-6-deoxy-6-beta-18F-fluoronaltrexone) was developed. The method utilizes reactor-produced [18F]-fluoride as its tetraethylammonium (TEA X F) salt in a SN2 displacement on a secondary triflate precursor. Typically, 45% of the 18F activity can be converted to the reactive TEAF in a 70 min preparation. From this, 35% yield (decay corrected) of the [18F]3-acetylcyclofoxy was obtained after HPLC purification with a specific activity of 25 Ci/mmol in a total synthesis time of 60 min.
Collapse
|
48
|
Koolpe GA, Nelson WL, Gioannini TL, Angel L, Simon EJ. Diastereomeric 6-desoxy-6-spiro-alpha-methylene-gamma-butyrolactone derivatives of naltrexone and oxymorphone. Selective irreversible inhibition of naltrexone binding in an opioid receptor preparation by a conformationally restricted michael acceptor ligand. J Med Chem 1984; 27:1718-23. [PMID: 6209395 DOI: 10.1021/jm00378a032] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The diastereomeric 6-desoxy-6-spiro-alpha-methylene-gamma-butyrolactone derivatives of naltrexone (4a and 5a) and of oxymorphone (4b and 5b) were prepared from their parent ketones. Diastereomers 4a and 4b were obtained from the 3,14-diacetate derivatives of naltrexone (6a) and oxymorphone (6b) by reaction with the Reformatsky reagent prepared from methyl alpha-(bromomethyl)acrylate. Deacetylation with methanol completed the synthesis. Diastereomers 5a and 5b were obtained from oxiranes 8a and 8b, respectively. The oxiranes were allowed to react with the sodium salt of ethyl acetoacetate, followed by methenation and deprotection to complete the synthesis of 5a and 5b, respectively. Compound 5a was the most potent agent tested in competition against [3H]naltrexone in the opioid radioreceptor assay. At a concentration of 5 nM this compound produced a 50% inhibition of binding. The majority of this inhibition (30%) was irreversible, i.e., it remained even after extensive washing of the membrane preparation in the presence and absence of Na+. Naloxone protected against this irreversible effect. The data suggest a receptor nucleophile, perhaps a sulfhydryl group, is located where it can add to the alpha, beta-unsaturated carbonyl system of 5a.
Collapse
|
49
|
Pert CB, Danks JA, Channing MA, Eckelman WC, Larson SM, Bennett JM, Burke TR, Rice KC. 3-[18F]Acetylcyclofoxy: a useful probe for the visualization of opiate receptors in living animals. FEBS Lett 1984; 177:281-6. [PMID: 6094248 DOI: 10.1016/0014-5793(84)81300-9] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.4] [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
A fluoro-analogue of the potent narcotic antagonist, naltrexone, was synthesized and shown to bind with high affinity to opiate receptors in vitro. 3-[18F]acetylcyclofoxy was prepared via a one-step triflate displacement reaction with the positron emitting 18F ion from tetraethylammonium [18F] fluoride. 3-[18F]acetylcyclofoxy accumulation in opiate receptor rich brain regions of both rat and baboon is shown to be completely displaced by the active enantiomer of naloxone [-)-naloxone) while the identical dose of the pharmacologically inert (+)-naloxone has no detectable effect. Moreover, both rat and baboon brain showed the well documented, typical opiate receptor distribution so that basal ganglia and thalamus are clearly visible in the living baboon brain up to 95 min after intravenous injection of 3-[18F] acetylcyclofoxy. We expect that 3-[18F )acetylcyclofoxy will be a useful probe for visualizing opiate receptors in living humans.
Collapse
|
50
|
Sayre LM, Larson DL, Takemori AE, Portoghese PS. Design and synthesis of naltrexone-derived affinity labels with nonequilibrium opioid agonist and antagonist activities. Evidence for the existence of different mu receptor subtypes in different tissues. J Med Chem 1984; 27:1325-35. [PMID: 6090663 DOI: 10.1021/jm00376a018] [Citation(s) in RCA: 24] [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: 01/18/2023]
Abstract
A series of beta-funaltrexamine (2, beta-FNA) analogues (3-14) were synthesized that contain a variety of electrophilic groups attached at the 6 beta-position of the opiate. The opioid agonist and antagonist activities of these ligands were evaluated in the guinea pig ileum (GPI) and mouse vas deferens (MVD) in vitro assays. Several of the compounds behaved like beta-FNA in that they exhibited reversible agonist activity at kappa opioid receptors and irreversible antagonist activity at mu opioid receptors. The rank order of irreversible antagonism for a series of related Michael acceptors did not parallel their intrinsic chemical reactivity, confirming that the degree of covalent binding is in part dependent on the spatial disposition of the electrophilic center relative to the receptor nucleophile (secondary recognition). The maleimidoacetamide 8 behaved very differently from beta-FNA in that it exhibited considerably greater irreversible mu antagonism in MVD relative to the mu blockage in the GPI. This suggests that different proportions of mu receptor subtypes exist in the two tissues. Several of the agents tested, including some nonreactive control compounds, displayed an unusual type of persistent kappa agonist activity in the GPI. This activity, which was reversed by addition of naloxone, reappeared upon washing. Receptor models have been presented to explain this effect. A few of the reactive ligands displayed a true nonreversible kappa agonist activity, suggesting a covalent association with the receptor. Of note in this regard was the propiolamide 6, which appeared to be an irreversible mixed agonist-antagonist at kappa and mu receptors.
Collapse
|