{"title":"Discovery and structure − activity relationships of 2,4,5-trimethoxyphenyl pyrimidine derivatives as selective D5 receptor partial agonists","authors":"","doi":"10.1016/j.bioorg.2024.107809","DOIUrl":null,"url":null,"abstract":"<div><p>Dopamine receptors are therapeutic targets for the treatment of various neurological and psychiatric disorders, including Parkinson’s and Alzheimer’s. Previously, PF-06649751 (tavapadon), PF-2562 and PW0464 have been discovered as potent and selective G protein-biased D1/D5 receptor agonists with optimal pharmacokinetic properties. However, no selective D5R agonist has been reported yet. In this context, we designed and synthesized forty non-catecholamines-based pyrimidine derivatives and identified four pyrimidine derivatives as selective D5R partial agonists. Using cAMP-based GloSensor assay in transiently transfected HEK293T cells with human D1 or D5 receptors, we discovered that compound <strong>5c</strong> (4-(4-bromophenyl)-6-(2,4,5-trimethoxyphenyl)pyrimidin-2-amine) exhibited modest D5R agonist activity. This leads us to explore various modifications of this scaffold to improve the D5 agonist potency and efficacy. Using molecular docking, and rational design followed by their evaluation at D1 and D5 receptors for agonist activity, we identified three new derivatives, <strong>5j</strong>, <strong>5</strong><strong>h</strong>, and <strong>5e</strong>. The most potent compound of this series <strong>5j</strong> (<em>4-(4-iodophenyl)-6-(2,4,5-trimethoxyphenyl)pyrimidin-2-amine),</em> exhibited EC<sub>50</sub> of 269.7 ± 6.6 nM. Mice microsomal stability studies revealed that <strong>5j</strong> is quite stable (>70 % at 1 hr). Furthermore, pharmacokinetic analysis of <strong>5j</strong> (20 mg/kg, p.o) in C57BL/6j mice showed that <strong>5j</strong> is readily absorbed via oral route of dosing and also enters into the brain (plasma T<sub>max</sub>: 1 h, C<sub>max</sub>: 51.10 ± 13.51 ng/ml; Brain T<sub>max</sub>: 0.5 h, C<sub>max</sub>: 22.54 ± 4.08 ng/ml). We further determined the <em>in-vivo</em> effect of <strong>5j</strong> on cognition in scopolamine-induced amnesia in C57BL/6j mice. We observed that <strong>5j</strong> (10 mg/kg, p.o) alleviated scopolamine-induced impairment in short-term memory and social recognition, which were blocked by D1/D5 antagonist SCH23390 (0.1 mg/kg, <em>i.p.</em>). Furthermore, <strong>5j</strong> did not exhibit any cytotoxicity (up to 10 µM) or <em>in vivo</em> acute toxicity up to 200 mg/kg (p.o). These results strongly suggest that <strong>5j</strong> could be further developed for treating neurological disorders wherein the D5 receptors play pivotal roles.</p></div>","PeriodicalId":257,"journal":{"name":"Bioorganic Chemistry","volume":null,"pages":null},"PeriodicalIF":4.5000,"publicationDate":"2024-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Bioorganic Chemistry","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0045206824007144","RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"BIOCHEMISTRY & MOLECULAR BIOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Dopamine receptors are therapeutic targets for the treatment of various neurological and psychiatric disorders, including Parkinson’s and Alzheimer’s. Previously, PF-06649751 (tavapadon), PF-2562 and PW0464 have been discovered as potent and selective G protein-biased D1/D5 receptor agonists with optimal pharmacokinetic properties. However, no selective D5R agonist has been reported yet. In this context, we designed and synthesized forty non-catecholamines-based pyrimidine derivatives and identified four pyrimidine derivatives as selective D5R partial agonists. Using cAMP-based GloSensor assay in transiently transfected HEK293T cells with human D1 or D5 receptors, we discovered that compound 5c (4-(4-bromophenyl)-6-(2,4,5-trimethoxyphenyl)pyrimidin-2-amine) exhibited modest D5R agonist activity. This leads us to explore various modifications of this scaffold to improve the D5 agonist potency and efficacy. Using molecular docking, and rational design followed by their evaluation at D1 and D5 receptors for agonist activity, we identified three new derivatives, 5j, 5h, and 5e. The most potent compound of this series 5j (4-(4-iodophenyl)-6-(2,4,5-trimethoxyphenyl)pyrimidin-2-amine), exhibited EC50 of 269.7 ± 6.6 nM. Mice microsomal stability studies revealed that 5j is quite stable (>70 % at 1 hr). Furthermore, pharmacokinetic analysis of 5j (20 mg/kg, p.o) in C57BL/6j mice showed that 5j is readily absorbed via oral route of dosing and also enters into the brain (plasma Tmax: 1 h, Cmax: 51.10 ± 13.51 ng/ml; Brain Tmax: 0.5 h, Cmax: 22.54 ± 4.08 ng/ml). We further determined the in-vivo effect of 5j on cognition in scopolamine-induced amnesia in C57BL/6j mice. We observed that 5j (10 mg/kg, p.o) alleviated scopolamine-induced impairment in short-term memory and social recognition, which were blocked by D1/D5 antagonist SCH23390 (0.1 mg/kg, i.p.). Furthermore, 5j did not exhibit any cytotoxicity (up to 10 µM) or in vivo acute toxicity up to 200 mg/kg (p.o). These results strongly suggest that 5j could be further developed for treating neurological disorders wherein the D5 receptors play pivotal roles.
期刊介绍:
Bioorganic Chemistry publishes research that addresses biological questions at the molecular level, using organic chemistry and principles of physical organic chemistry. The scope of the journal covers a range of topics at the organic chemistry-biology interface, including: enzyme catalysis, biotransformation and enzyme inhibition; nucleic acids chemistry; medicinal chemistry; natural product chemistry, natural product synthesis and natural product biosynthesis; antimicrobial agents; lipid and peptide chemistry; biophysical chemistry; biological probes; bio-orthogonal chemistry and biomimetic chemistry.
For manuscripts dealing with synthetic bioactive compounds, the Journal requires that the molecular target of the compounds described must be known, and must be demonstrated experimentally in the manuscript. For studies involving natural products, if the molecular target is unknown, some data beyond simple cell-based toxicity studies to provide insight into the mechanism of action is required. Studies supported by molecular docking are welcome, but must be supported by experimental data. The Journal does not consider manuscripts that are purely theoretical or computational in nature.
The Journal publishes regular articles, short communications and reviews. Reviews are normally invited by Editors or Editorial Board members. Authors of unsolicited reviews should first contact an Editor or Editorial Board member to determine whether the proposed article is within the scope of the Journal.