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<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">Front. Pharmacol.</journal-id>
<journal-title>Frontiers in Pharmacology</journal-title>
<abbrev-journal-title abbrev-type="pubmed">Front. Pharmacol.</abbrev-journal-title>
<issn pub-type="epub">1663-9812</issn>
<publisher>
<publisher-name>Frontiers Media S.A.</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="publisher-id">1231450</article-id>
<article-id pub-id-type="doi">10.3389/fphar.2023.1231450</article-id>
<article-categories>
<subj-group subj-group-type="heading">
<subject>Pharmacology</subject>
<subj-group>
<subject>Original Research</subject>
</subj-group>
</subj-group>
</article-categories>
<title-group>
<article-title>Natural product-inspired synthesis of coumarin&#x2013;chalcone hybrids as potential anti-breast cancer agents</article-title>
<alt-title alt-title-type="left-running-head">Alhakamy et al.</alt-title>
<alt-title alt-title-type="right-running-head">
<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fphar.2023.1231450">10.3389/fphar.2023.1231450</ext-link>
</alt-title>
</title-group>
<contrib-group>
<contrib contrib-type="author" equal-contrib="yes">
<name>
<surname>Alhakamy</surname>
<given-names>Nabil A.</given-names>
</name>
<xref ref-type="aff" rid="aff1">
<sup>1</sup>
</xref>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
<xref ref-type="author-notes" rid="fn001">
<sup>&#x2020;</sup>
</xref>
<uri xlink:href="https://loop.frontiersin.org/people/937681/overview"/>
</contrib>
<contrib contrib-type="author" equal-contrib="yes">
<name>
<surname>Saquib</surname>
<given-names>Mohammad</given-names>
</name>
<xref ref-type="aff" rid="aff4">
<sup>4</sup>
</xref>
<xref ref-type="author-notes" rid="fn001">
<sup>&#x2020;</sup>
</xref>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Sanobar</surname>
</name>
<xref ref-type="aff" rid="aff5">
<sup>5</sup>
</xref>
<xref ref-type="aff" rid="aff6">
<sup>6</sup>
</xref>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Khan</surname>
<given-names>Mohammad Faheem</given-names>
</name>
<xref ref-type="aff" rid="aff7">
<sup>7</sup>
</xref>
<uri xlink:href="https://loop.frontiersin.org/people/2262107/overview"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Ansari</surname>
<given-names>Waseem Ahmad</given-names>
</name>
<xref ref-type="aff" rid="aff7">
<sup>7</sup>
</xref>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Arif</surname>
<given-names>Deema O.</given-names>
</name>
<xref ref-type="aff" rid="aff2">
<sup>2</sup>
</xref>
<xref ref-type="aff" rid="aff3">
<sup>3</sup>
</xref>
<xref ref-type="aff" rid="aff8">
<sup>8</sup>
</xref>
<uri xlink:href="https://loop.frontiersin.org/people/2330846/overview"/>
</contrib>
<contrib contrib-type="author">
<name>
<surname>Irfan</surname>
<given-names>Mohammad</given-names>
</name>
<xref ref-type="aff" rid="aff9">
<sup>9</sup>
</xref>
</contrib>
<contrib contrib-type="author" corresp="yes">
<name>
<surname>Khan</surname>
<given-names>Mohammad Imran</given-names>
</name>
<xref ref-type="aff" rid="aff10">
<sup>10</sup>
</xref>
<xref ref-type="aff" rid="aff11">
<sup>11</sup>
</xref>
<xref ref-type="corresp" rid="c001">&#x2a;</xref>
<uri xlink:href="https://loop.frontiersin.org/people/299236/overview"/>
</contrib>
<contrib contrib-type="author" corresp="yes">
<name>
<surname>Hussain</surname>
<given-names>Mohd Kamil</given-names>
</name>
<xref ref-type="aff" rid="aff5">
<sup>5</sup>
</xref>
<xref ref-type="aff" rid="aff6">
<sup>6</sup>
</xref>
<xref ref-type="corresp" rid="c001">&#x2a;</xref>
<uri xlink:href="https://loop.frontiersin.org/people/527271/overview"/>
</contrib>
</contrib-group>
<aff id="aff1">
<sup>1</sup>
<institution>Department of Pharmaceutics</institution>, <institution>Faculty of Pharmacy</institution>, <institution>King Abdulaziz University</institution>, <addr-line>Jeddah</addr-line>, <country>Saudi Arabia</country>
</aff>
<aff id="aff2">
<sup>2</sup>
<institution>Mohamed Saeed Tamer Chair for Pharmaceutical Industries</institution>, <institution>Faculty of Pharmacy</institution>, <institution>King Abdulaziz University</institution>, <addr-line>Jeddah</addr-line>, <country>Saudi Arabia</country>
</aff>
<aff id="aff3">
<sup>3</sup>
<institution>Center of Excellence for Drug Research and Pharmaceutical Industries</institution>, <institution>King Abdulaziz University</institution>, <addr-line>Jeddah</addr-line>, <country>Saudi Arabia</country>
</aff>
<aff id="aff4">
<sup>4</sup>
<institution>Department of Chemistry</institution>, <institution>University of Allahabad</institution>, <addr-line>Prayagraj</addr-line>, <country>India</country>
</aff>
<aff id="aff5">
<sup>5</sup>
<institution>Department of Chemistry</institution>, <institution>Government Raza Post Graduate College</institution>, <addr-line>Rampur</addr-line>, <country>India</country>
</aff>
<aff id="aff6">
<sup>6</sup>
<institution>M. J. P. Rohilkhand University</institution>, <addr-line>Bareilly</addr-line>, <country>India</country>
</aff>
<aff id="aff7">
<sup>7</sup>
<institution>Department of Biotechnology</institution>, <institution>Era&#x2019;s Lucknow Medical College</institution>, <institution>Era University</institution>, <addr-line>Lucknow</addr-line>, <country>India</country>
</aff>
<aff id="aff8">
<sup>8</sup>
<institution>Faculty of Medicine</institution>, <institution>Ibn Sina National College</institution>, <addr-line>Jeddah</addr-line>, <country>Saudi Arabia</country>
</aff>
<aff id="aff9">
<sup>9</sup>
<institution>Department of Medicine</institution>, <institution>Jawaharlal Nehru Medical College and Hospital</institution>, <institution>Aligarh Muslim University (AMU)</institution>, <addr-line>Aligarh</addr-line>, <country>India</country>
</aff>
<aff id="aff10">
<sup>10</sup>
<institution>Departments of Biochemistry</institution>, <institution>Faculty of Science</institution>, <institution>King Abdulaziz University</institution>, <addr-line>Jeddah</addr-line>, <country>Saudi Arabia</country>
</aff>
<aff id="aff11">
<sup>11</sup>
<institution>Centre of Artificial Intelligence in Precision Medicine</institution>, <institution>King Abdulaziz University</institution>, <addr-line>Jeddah</addr-line>, <country>Saudi Arabia</country>
</aff>
<author-notes>
<fn fn-type="edited-by">
<p>
<bold>Edited by:</bold> <ext-link ext-link-type="uri" xlink:href="https://loop.frontiersin.org/people/1840762/overview">Asim Mansha</ext-link>, Government College University, Pakistan</p>
</fn>
<fn fn-type="edited-by">
<p>
<bold>Reviewed by:</bold> <ext-link ext-link-type="uri" xlink:href="https://loop.frontiersin.org/people/1734878/overview">Chang Liu</ext-link>, University of Rhode Island, United States</p>
<p>
<ext-link ext-link-type="uri" xlink:href="https://loop.frontiersin.org/people/983665/overview">Sidharth Mehan</ext-link>, Indo-Soviet Friendship College of Pharmacy, India</p>
</fn>
<corresp id="c001">&#x2a;Correspondence: Mohammad Imran Khan, <email>mikhan@kau.edu.sa</email>; Mohd Kamil Hussain, <email>mkhcdri@gmail.com</email>
</corresp>
<fn fn-type="equal" id="fn001">
<label>
<sup>&#x2020;</sup>
</label>
<p>These authors have contributed equally to this work and share first authorship</p>
</fn>
</author-notes>
<pub-date pub-type="epub">
<day>06</day>
<month>09</month>
<year>2023</year>
</pub-date>
<pub-date pub-type="collection">
<year>2023</year>
</pub-date>
<volume>14</volume>
<elocation-id>1231450</elocation-id>
<history>
<date date-type="received">
<day>30</day>
<month>05</month>
<year>2023</year>
</date>
<date date-type="accepted">
<day>18</day>
<month>08</month>
<year>2023</year>
</date>
</history>
<permissions>
<copyright-statement>Copyright &#xa9; 2023 Alhakamy, Saquib, Sanobar, Khan, Ansari, Arif, Irfan, Khan and Hussain.</copyright-statement>
<copyright-year>2023</copyright-year>
<copyright-holder>Alhakamy, Saquib, Sanobar, Khan, Ansari, Arif, Irfan, Khan and Hussain</copyright-holder>
<license xlink:href="http://creativecommons.org/licenses/by/4.0/">
<p>This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.</p>
</license>
</permissions>
<abstract>
<p>Twelve novel neo-tanshinlactone&#x2013;chalcone hybrid molecules were constructed through a versatile methodology involving the Horner&#x2013;Wadsworth&#x2013;Emmons (HWE) olefination of 4-formyl-<italic>2H</italic>-benzo [<italic>h</italic>]chromen-2-ones and phosphonic acid diethyl esters, as the key step, and evaluated for anticancer activity against a series of four breast cancers and their related cell lines, <italic>viz.</italic> MCF-7 (ER &#x2b; ve), MDA-MB-231 (ER-ve), HeLa (cervical cancer), and Ishikawa (endometrial cancer). The title compounds showed excellent to moderate <italic>in vitro</italic> anti-cancer activity in a range of 6.8&#x2013;19.2&#xa0;&#xb5;M (IC<sub>50</sub>). Compounds <bold>30 (</bold>IC<sub>50</sub> &#x3d; 6.8&#xa0;&#xb5;M and MCF-7; IC<sub>50</sub> &#x3d; 8.5&#xa0;&#xb5;M and MDA-MB-231) and <bold>31 (</bold>IC<sub>50</sub> &#x3d; 14.4 &#xb5;M and MCF-7; IC<sub>50</sub> &#x3d; 15.7&#xa0;&#xb5;M and MDA-MB-231) exhibited the best activity with compound <bold>30</bold> showing more potent activity than the standard drug tamoxifen. Compound <bold>30</bold> demonstrated a strong binding affinity with tumor necrosis factor &#x3b1; (TNF-&#x3b1;) in molecular docking studies. This is significant because TNF&#x3b1; is linked to MCF-7 cancer cell lines, and it enhances luminal breast cancer cell proliferation by upregulating aromatase. Additionally, virtual ADMET studies confirmed that hybrid compounds <bold>30</bold> and <bold>31</bold> met Lipinski&#x2019;s rule; displayed high bioavailability, excellent oral absorption, favorable albumin interactions, and strong penetration capabilities; and improved blood&#x2013;brain barrier crossing. Based on the aforementioned results, compound <bold>30</bold> has been identified as a potential anti-breast cancer lead molecule.</p>
</abstract>
<kwd-group>
<kwd>breast cancer</kwd>
<kwd>coumarins</kwd>
<kwd>chalcones</kwd>
<kwd>neo-tanshinlactone</kwd>
<kwd>hybrid molecules</kwd>
</kwd-group>
<custom-meta-wrap>
<custom-meta>
<meta-name>section-at-acceptance</meta-name>
<meta-value>Experimental Pharmacology and Drug Discovery</meta-value>
</custom-meta>
</custom-meta-wrap>
</article-meta>
</front>
<body>
<sec id="s1">
<title>1 Introduction</title>
<p>Breast carcinoma is the most commonly diagnosed cancer and the leading cause of death from cancer disease globally. In the year 2020, approximately 23 million new cases of breast cancer (11.7% of all cancer cases) were estimated worldwide (<xref ref-type="bibr" rid="B30">Siegel et al., 2020</xref>; <xref ref-type="bibr" rid="B31">Sung et al., 2021</xref>; <xref ref-type="bibr" rid="B25">Saquib et al., 2023</xref>). Despite the achievements and advances made in the chemotherapy of cancers during the past 20&#xa0;years, the emergence of drug resistance continues to be a major issue in cancer treatment. Increasing prevalence of drug resistance combined with issues of tissue selectivity and toxicity in cancer chemotherapy has necessitated further research toward the development of less toxic and more effective therapeutic anti-breast cancer agents (<xref ref-type="bibr" rid="B26">Saquib et al., 2019</xref>). The search for small-molecule inhibitors (SMIs) based on novel molecular scaffolds that exhibit unique medicinal properties is largely inspired by biologically relevant molecules, primarily natural products (NPs). The structural diversity of NPs provides a rich source of molecular scaffolds that can be used as starting points for the design and discovery of new SMIs. By studying the structural features of NPs, researchers can identify new therapeutic agents with improved pharmacokinetic properties, increased potency, and reduced toxicity. However, the full potential of NPs in the design of new scaffolds for drug discovery is currently limited by the scarcity of guiding synthetic strategies available for this purpose. In this milieu, molecular hybridization can be a very useful tool (<xref ref-type="bibr" rid="B15">Li and Vederas, 2009</xref>; <xref ref-type="bibr" rid="B38">Wetzel et al., 2011</xref>). This approach involves combining two or more pharmacophoric units to obtain novel compounds with enhanced therapeutic properties and is finding increasing applications in the fields of drug discovery and medicinal chemistry (<xref ref-type="bibr" rid="B19">Meunier, 2008</xref>; <xref ref-type="bibr" rid="B3">Bosquesi et al., 2011</xref>; <xref ref-type="bibr" rid="B28">Saquib et al., 2013</xref>; <xref ref-type="bibr" rid="B35">Tukulula et al., 2013</xref>; <xref ref-type="bibr" rid="B32">&#x160;venda et al., 2015</xref>) (<xref ref-type="fig" rid="F1">Figure 1</xref>) (<xref ref-type="bibr" rid="B33">Tietze et al., 2003</xref>).</p>
<fig id="F1" position="float">
<label>FIGURE 1</label>
<caption>
<p>Approaches for the construction of small natural product hybrid molecules.</p>
</caption>
<graphic xlink:href="fphar-14-1231450-g001.tif"/>
</fig>
<p>2-Methoxyestradiol&#x2013;colchicine hybrids and estrone&#x2013;talaromycin hybrids are interesting examples of NP-based hybrid scaffolds. 2-Methoxyestradiol&#x2013;colchicine hybrids were found to be more active as compared to the parent molecules against the tubulin polymerization assembly. 2-Methoxyestradiol&#x2013;colchicine hybrid <bold>A</bold> inhibited polymerization of tubulin (IC<sub>50</sub> &#x3d; 2.1&#xa0;&#xb5;M) with greater potency as compared to parent molecules 2-methoxyestradiol (2-ME) (IC<sub>50</sub> &#x3d; 14.2&#xa0;&#xb5;M) and colchicine (IC<sub>50</sub> &#x3d; 11.2&#xa0;&#xb5;M) (<xref ref-type="bibr" rid="B20">Miller et al., 1997</xref>). The estrone&#x2013;talaromycin hybrid (<bold>B</bold>), which was designed through the <italic>de novo</italic> combination of fragments of talaromycin B and estrone nucleus, exhibited better cytotoxic activity as compared to talaromycin B (<xref ref-type="fig" rid="F2">Figure 2</xref>) (<xref ref-type="bibr" rid="B34">Tietze et al., 1998</xref>).</p>
<fig id="F2" position="float">
<label>FIGURE 2</label>
<caption>
<p>Design of biologically relevant natural product hybrids as anticancer agents.</p>
</caption>
<graphic xlink:href="fphar-14-1231450-g002.tif"/>
</fig>
<p>Several naturally occurring and synthetic coumarin derivatives have been reported to exhibit potent anti-cancer activity including anti-breast cancer activity (<xref ref-type="bibr" rid="B22">Musa et al., 2008</xref>; <xref ref-type="bibr" rid="B14">K&#xfc;peli Akkol et al., 2020</xref>). Neo-tanshinlactone, a benzocoumarin isolated from the underground stem of <italic>Salvia miltiorrhiza</italic>, inhibited the proliferation of MCF-7 cell lines more effectively than the anti-breast cancer drug tamoxifen (<xref ref-type="bibr" rid="B36">Wang et al., 2004</xref>; <xref ref-type="bibr" rid="B16">Lin et al., 2016</xref>). Likewise, chalcone is an important pharmacophore widely distributed in many natural products. Various natural and synthetic chalcones have been reported to show excellent biological activities including anticancer activity (<xref ref-type="bibr" rid="B17">Malek et al., 2011</xref>; <xref ref-type="bibr" rid="B39">Zhang et al., 2013</xref>; <xref ref-type="bibr" rid="B40">Zhuang et al., 2017</xref>). Moreover, a naturally occurring coumarin&#x2013;chalcone hybrid isolated from the leaves of <italic>Cyclosorus parasiticus</italic> have been found to be cytotoxic (<xref ref-type="bibr" rid="B24">Quadri-Spinelli et al., 2000</xref>; <xref ref-type="bibr" rid="B37">Wei et al., 2013</xref>).</p>
<p>The interesting pharmacological properties of the neo-tanshinlactone and the chalcone scaffolds inspired us to design the neo-tanshinlactone&#x2013;chalcone hybrid molecules (coumarin&#x2013;chalcone hybrids) by the <italic>de novo</italic> combination of both these scaffolds onto one template (<xref ref-type="fig" rid="F3">Figure 3</xref>).</p>
<fig id="F3" position="float">
<label>FIGURE 3</label>
<caption>
<p>Basis of work: combination of neo-tanshinlactone and the chalcone units to obtain neo-tanshinlactone&#x2013;chalcone hybrids. (a) (<xref ref-type="bibr" rid="B36">Wang et al., 2004</xref>); (b) (<xref ref-type="bibr" rid="B39">Zhang et al., 2013</xref>); (c) (<xref ref-type="bibr" rid="B17">Malek et al., 2011</xref>); and (d) (<xref ref-type="bibr" rid="B24">Quadri-Spinelli et al., 2000</xref>; <xref ref-type="bibr" rid="B37">Wei et al., 2013</xref>).</p>
</caption>
<graphic xlink:href="fphar-14-1231450-g003.tif"/>
</fig>
</sec>
<sec sec-type="results|discussion" id="s2">
<title>2 Results and discussion</title>
<p>The synthesis of the target hybrid molecules was envisaged by the coupling of <italic>&#x3b2;</italic>-aryl-<italic>&#x3b2;</italic>-ketophosphonates (<bold>13&#x2013;17</bold>) with the 4-formyl-2<italic>H</italic>-benzo [<italic>h</italic>]chromen-2-ones (<bold>24</bold>&#x2013;<bold>25</bold>) (<xref ref-type="fig" rid="F4">Figure 4</xref>) using the Horner&#x2013;Wadsworth&#x2013;Emmons (HWE) reaction, a versatile and efficient synthetic tool for the synthesis of diverse types of chalcone molecules and stilbene derivatives. The HWE reaction would allow us to synthesize a library of the target chalcones in quantitative yields. <italic>&#x3b2;</italic>-aryl-<italic>&#x3b2;</italic>-ketophosphonates (<bold>13</bold>&#x2013;<bold>17</bold>) were prepared by the Michaelis&#x2013;Arbuzov reaction of substituted phenacyl bromides and triethylphoshphite (<xref ref-type="fig" rid="F5">Figure 5</xref>) (<xref ref-type="bibr" rid="B4">Debrouwer et al., 2013</xref>; <xref ref-type="bibr" rid="B5">Dunny et al., 2013</xref>; <xref ref-type="bibr" rid="B27">Saquib et al., 2021</xref>). 4-Formyl-2<italic>H</italic>-benzo [<italic>h</italic>]chromen-2-ones, <bold>24</bold>&#x2013;<bold>25</bold>, on the other hand, were synthesized by the Riley oxidation of 4-methyl-2<italic>H</italic>-benzo [h]chromen-2-ones, <bold>22</bold>&#x2013;<bold>23</bold>, in quantitative yields, which, in turn, were synthesized in excellent yields through an acid-catalyzed Pechmann condensation of ethyl acetoacetate (EAA) and 2-naphthols, <bold>20&#x2013;21</bold>, at room temperature (<xref ref-type="fig" rid="F6">Figure 6</xref>).</p>
<fig id="F4" position="float">
<label>FIGURE 4</label>
<caption>
<p>Outline for the synthesis of neo-tanshinlactone&#x2013;chalcone hybrids.</p>
</caption>
<graphic xlink:href="fphar-14-1231450-g004.tif"/>
</fig>
<fig id="F5" position="float">
<label>FIGURE 5</label>
<caption>
<p>Preparation of <italic>&#x3b2;</italic>-aryl-<italic>&#x3b2;</italic>-ketophosphonates (<bold>13&#x2013;17</bold>) through the Michaelis&#x2013;Arbuzov reaction; reagent and conditions: (a) Br<sub>2</sub>, Et<sub>2</sub>O, and (b) P(OEt)<sub>3</sub>.</p>
</caption>
<graphic xlink:href="fphar-14-1231450-g005.tif"/>
</fig>
<fig id="F6" position="float">
<label>FIGURE 6</label>
<caption>
<p>Reagent and conditions for the synthesis of 4-formyl-<italic>2H</italic>-benzo [<italic>h</italic>]chromen-2-ones; (a) MeI (1equiv), anhyd. K<sub>2</sub>CO<sub>3</sub>, acetone; (b) Cat conc. H<sub>2</sub>SO<sub>4</sub>, RT; (c) SeO<sub>2</sub>, xylene, reflux.</p>
</caption>
<graphic xlink:href="fphar-14-1231450-g006.tif"/>
</fig>
<p>Finally, the olefination of &#x3b2;-aryl-&#x3b2;-ketophosphonates, <bold>13</bold>&#x2013;<bold>17</bold>, with 4-formyl-2H-benzo [h]chromen-2-ones, <bold>24</bold>&#x2013;<bold>25</bold>, in dry DMF/MeONa led to the synthesis of 2H-benzo [h]chromen-2-ones&#x2013;chalcone hybrids (neo-tanshinlactone&#x2013;chalcone hybrids), <bold>26&#x2013;37</bold>, in excellent yields (95%&#x2013;97%) (<xref ref-type="fig" rid="F7">Figure 7</xref>). The synthesized compounds <bold>26&#x2013;37</bold> were purified by recrystallization using ethyl acetate. We confirmed the structures of these compounds by NMR spectroscopy, mass spectrometry, and elemental analysis.</p>
<fig id="F7" position="float">
<label>FIGURE 7</label>
<caption>
<p>Reagents and conditions for the synthesis of neo-tanshinlactone&#x2013;chalcone hybrids; (a) NaOMe, Anhyd DMF, and RT.</p>
</caption>
<graphic xlink:href="fphar-14-1231450-g007.tif"/>
</fig>
</sec>
<sec id="s3">
<title>3 <italic>In vitro</italic> antiproliferative activities of the synthesized compounds</title>
<p>We conducted an <italic>in vitro</italic> MTT assay to evaluate the anti-cancer activity of the synthesized neo-tanshinlactone&#x2013;chalcone hybrid compounds, <bold>26</bold>&#x2013;<bold>37</bold>, against four human cancer cell lines, namely, MCF-7 (breast cancer), MDA-MB-231 (breast cancer), Ishikawa (endometrial cancer), and HeLa (cervical cancer). The toxicity of the hybrid molecules on the normal human embryonic kidney cell line HEK-293 was also evaluated.</p>
<p>From among the evaluated molecules, four compounds, i.e., <bold>26</bold>, <bold>30</bold>, <bold>31</bold>, and <bold>33</bold>, showed anti-cancer activity against MCF-7 cell lines. These compounds had methoxy substituents at the 3&#x2032;, 5&#x2032;, and 3&#x2032;, 4&#x2032;, and 5&#x2032; positions of the aroyl rings. Additionally, compounds <bold>26</bold>, <bold>30</bold>, and <bold>31</bold> also exhibited anti-cancer activity against MDA-MB-231 cell lines. Among these, <bold>30</bold> showed the highest anti-cancer activity against both MCF-7 and MDA-MB-231 cell lines with IC<sub>50</sub> values of 6.8&#xa0;&#xb5;M and 8.5&#xa0;&#xb5;M, respectively (<xref ref-type="table" rid="T1">Table 1</xref>; <xref ref-type="fig" rid="F8">Figures 8A,B</xref>). However, these compounds did not show activity against Ishikawa and HeLa cell lines (IC<sub>50</sub> &#x3e; 20&#xa0;&#xb5;M).</p>
<table-wrap id="T1" position="float">
<label>TABLE 1</label>
<caption>
<p>
<italic>In vitro</italic> anti-cancer activity and receptor-binding affinity of hybrid compounds, 26&#x2013;37, against various cancer cell lines.</p>
</caption>
<table>
<thead valign="top">
<tr>
<th rowspan="2" align="center">S. No.</th>
<th rowspan="2" align="center">Comp. no.</th>
<th colspan="5" align="center">IC<sub>50</sub> values (mean &#xb1; SEM, in &#x3bc;M)</th>
</tr>
<tr>
<th align="left">MCF-7</th>
<th align="left">MDA-MB-231</th>
<th align="left">Ishikawa</th>
<th align="left">HeLa</th>
<th align="left">HEK-293</th>
</tr>
</thead>
<tbody valign="top">
<tr>
<td align="center">1</td>
<td align="center">
<bold>26</bold>
</td>
<td align="center">
<bold>17.2 &#xb1; 1.75</bold>
</td>
<td align="center">
<bold>16.6 &#xb1; 1.25</bold>
</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
</tr>
<tr>
<td align="center">2</td>
<td align="center">27</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
<td align="center">17.4 <bold>&#xb1;</bold> 2.72</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
</tr>
<tr>
<td align="center">3</td>
<td align="center">28</td>
<td align="center">
<bold>18.6 &#xb1; 2.30</bold>
</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
</tr>
<tr>
<td align="center">4</td>
<td align="center">29</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
</tr>
<tr>
<td align="center">5</td>
<td align="center">30</td>
<td align="center">
<bold>6.8 &#xb1; 1.48</bold>
</td>
<td align="center">
<bold>8.5 &#xb1; 1.12</bold>
</td>
<td align="center">ND</td>
<td align="center">ND</td>
<td align="center">&#x3e;20</td>
</tr>
<tr>
<td align="center">6</td>
<td align="center">31</td>
<td align="center">
<bold>14.4 &#xb1; 1.68</bold>
</td>
<td align="center">
<bold>15.7 &#xb1; 1.01</bold>
</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
</tr>
<tr>
<td align="center">7</td>
<td align="center">32</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
<td align="center">ND</td>
<td align="center">ND</td>
<td align="center">&#x3e;20</td>
</tr>
<tr>
<td align="center">8</td>
<td align="center">33</td>
<td align="center">
<bold>16.3 &#xb1; 2.30</bold>
</td>
<td align="center">
<bold>&#x3e;</bold>20</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
</tr>
<tr>
<td align="center">9</td>
<td align="center">34</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
</tr>
<tr>
<td align="center">10</td>
<td align="center">35</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
</tr>
<tr>
<td align="center">11</td>
<td align="center">36</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
<td align="center">19.2 &#xb1; 3.12</td>
<td align="center">16.8 &#xb1; 3.14</td>
<td align="center">&#x3e;20</td>
</tr>
<tr>
<td align="center">12</td>
<td align="center">37</td>
<td align="center">&#x3e;20</td>
<td align="center">&#x3e;20</td>
<td align="center">18.6 &#xb1; 2.56</td>
<td align="center">17.2 &#xb1; 2.88</td>
<td align="center">&#x3e;20</td>
</tr>
<tr>
<td align="center">13</td>
<td align="center">TAM</td>
<td align="center">11.2 &#xb1; 2.36</td>
<td align="center">15.5 &#xb1; 2.64</td>
<td align="center">ND</td>
<td align="center">ND</td>
<td align="center">18.8 &#xb1; 2.22</td>
</tr>
</tbody>
</table>
<table-wrap-foot>
<fn>
<p>The bold values represent the IC<sub>50</sub> values of compounds showing significant anti-cancer activity.</p>
</fn>
</table-wrap-foot>
</table-wrap>
<fig id="F8" position="float">
<label>FIGURE 8</label>
<caption>
<p>
<bold>(A)</bold> Cytotoxicity assay of compounds <bold>26</bold>&#x2013;<bold>33</bold> in MCF-7 cells. <bold>(B)</bold> Cytotoxicity assay of <bold>26</bold>&#x2013;<bold>33</bold> in MCF-7 cells in MDA-MB-231 cells: results are expressed as mean &#xb1; SE; n &#x3d; 5; <italic>p</italic> values are a-p&#x3c;0.001, b-p&#x3c;0.01, c-p&#x3c;0.05, and d &#x3e; 0.05.</p>
</caption>
<graphic xlink:href="fphar-14-1231450-g008.tif"/>
</fig>
<p>Similarly, compound <bold>31</bold> also exhibited potent inhibitions against MCF-7 and MDA-MB-231 cell lines with IC<sub>50</sub> values of 14.4&#xa0;&#xb5;M and 15.7&#xa0;&#xb5;M, respectively, while compound <bold>26</bold> exhibited anti-cancer activity with IC<sub>50</sub> values of 17.2&#xa0;&#xb5;M and 16.6&#xa0;&#xb5;M, respectively, in both of these cell lines. Molecules <bold>34</bold>, <bold>35</bold>, <bold>36</bold>, and <bold>37</bold> having chloro substituents on the aroyl ring were found inactive against MCF-7 and MDA-MB-231 cell lines (IC<sub>50</sub> &#x3e; 20&#xa0;&#xb5;M); however, compounds <bold>36</bold> and <bold>37</bold> showed good antiproliferative activity against Ishikawa and HeLa cell lines. Molecule <bold>36</bold> showed anti-cancer activity against Ishikawa and HeLa cell lines and with IC<sub>50</sub> values of 19.2&#xa0;&#xb5;M and 16.8&#xa0;&#xb5;M, respectively, while compound <bold>37</bold> exhibited inhibition against Ishikawa and HeLa cell lines with IC<sub>50</sub> values of 18.6&#xa0;&#xb5;M and 17.2&#xa0;&#xb5;M, respectively. Molecules <bold>29</bold> and <bold>32</bold> having unsubstituted aroyl rings were found inactive (IC<sub>50</sub> &#x3e; 20&#xa0;&#xb5;M) against all the four cancer cell lines. The results of the assay showed that the synthesized compounds had significant anti-cancer activity against all the four cell lines.</p>
<p>Interestingly, all the evaluated compounds were found to be non-toxic to normal HEK-293 cells with an IC<sub>50</sub> value greater than 20&#xa0;&#xb5;M. This result indicates that the synthesized compounds, particularly compounds <bold>30</bold> and <bold>31</bold>, could be good candidates for further lead optimization.</p>
</sec>
<sec id="s4">
<title>4 Analysis of molecular docking</title>
<p>We conducted a molecular docking study for all the synthesized compounds, <bold>26&#x2013;37</bold>, to investigate their binding interactions with the target proteins of cancer cell lines. The target proteins such as tumor necrosis factor &#x3b1; (TNF-&#x3b1;), c-Jun N-terminal kinase (JNK), mitogen-activated protein kinase (MAPK), and nuclear factor-kB (Nf-kB) were selected based on their involvement in cell proliferation, which is a key hallmark of cancer. The docking scores of the compounds provided an estimate of their binding affinity to the target proteins. This study can help us understand how these compounds interact with cancer cells and thus potentially lead to the development of new cancer agents. The docking scores of the compounds are shown in <xref ref-type="table" rid="T2">Table 2</xref>. The binding affinities of all docked compounds were in complete agreement with the obtained <italic>in vitro</italic> results and showed that compounds <bold>30</bold> and <bold>31</bold> exhibited potent inhibitory activities against TNF-&#x3b1;, JNK, MAPK, and Nf-kB targets. Considering the effect of hydrogen bonds, hydrophobic, electrostatic, and pi&#x2013;pi interactions, the docking results revealed that all the compounds, <bold>6</bold>&#x2013;<bold>37</bold>, displayed significant docking scores ranging from &#x2212;7.508 to &#x2212;10.170&#xa0;kcal/mol against the TNF-&#x3b1; target, &#x2212;6.867 to &#x2212;7.516&#xa0;kcal/mol against the JNK target, &#x2212;3.936 to &#x2212;5.285&#xa0;kcal/mol against the MAPK target, and &#x2212;3.257 to &#x2212;4.507&#xa0;kcal/mol against the NF-kB target, respectively (<xref ref-type="bibr" rid="B18">Mendie and Hemalatha, 2022</xref>). Compound <bold>30</bold> demonstrated polar and hydrophobic interactions with Ser60 and Gln61, and Leu57, Ile58, Tyr119, Leu120, Tyr151, and Ile155 amino acids of TNF-&#x3b1; protein (<xref ref-type="fig" rid="F9">Figure 9A</xref>). Similarly, compound <bold>30</bold> displayed H-bonding with Met109, and polar and hydrophobic interactions with Ser32, Thr106, and Hie107, and Val30, Tyr35, Val38, Ala51, Leu74, Leu75, Ile84, Leu108, Phe169, Leu171, and Ala172 amino acids of the MAPK target (<xref ref-type="fig" rid="F9">Figure 9C</xref>). Compound <bold>30</bold> also exhibited H-bonding with Arg59 and Tyr82 along with pi&#x2013;pi, pi&#x2013;cation, polar, and hydrophobic interactions with Phe56, Lys80, Hie67, Asn139, Asn250, and Pro71 amino acids of the NF-kB target (<xref ref-type="fig" rid="F9">Figure 9D</xref>). On the other hand, compound <bold>31</bold> showed H-bonding with Asn109, and polar and hydrophobic interactions with Ser72, Gln75, Asn152, Gln155, Ser193, Thr226, Ile70, Ala74, Val74, Ala91, Met146, Leu148, Met149, and Ala151 amino acids of JNK protein (<xref ref-type="fig" rid="F9">Figure 9B</xref>). Additionally, tamoxifen (control drug) exhibited polar and hydrophobic interactions with Ser60 and Ser61, and Leu57, Ile58, Tyr59, Tyr119, Leu120, Val123, Tyr151, and Ile155 amino acids of TNF-&#x3b1; protein (<xref ref-type="fig" rid="F10">Figure 10A</xref>). Moreover, tamoxifen also showed polar and hydrophobic interactions with Ser72, Asn152, Gln155, Ser193, and Asn194, and Ile70, Val78, Ala91, Ile124, Leu148, Met149, and Ala151 amino acids of the JNK target (<xref ref-type="fig" rid="F10">Figure 10B</xref>). Tamoxifen showed salt bridge, pi&#x2013;cation, and hydrophobic interactions with Glu71 and Lys53, and Tyr35, Val38, Ala51, val52, Leu75, Ile84, Leu86, Leu104, Val105, Leu108, Met109, Leu167, Phe169, Leu171, and Ala172 amino acids of MAPK protein (<xref ref-type="fig" rid="F10">Figure 10C</xref>). Tamoxifen also displayed H-bonding, pi&#x2013;cation, polar and hydrophobic interactions with Ser74, Lys80, Hie67, Ser75, and Asn139, and Phe56, Pro71, Ala73, and Tyr82 amino acids of NF-kB protein (<xref ref-type="fig" rid="F10">Figure 10D</xref>) (<xref ref-type="bibr" rid="B7">Guerrero-Perilla et al., 2015</xref>).</p>
<table-wrap id="T2" position="float">
<label>TABLE 2</label>
<caption>
<p>Docking scores of compounds, 26&#x2013;37, against the target proteins which are involved in cell proliferation.</p>
</caption>
<table>
<thead valign="top">
<tr>
<th align="left">Comp no.</th>
<th align="center">TNF-&#x3b1; (6X81)</th>
<th align="center">JNK (1JNK)</th>
<th align="center">MAPK(1A9U)</th>
<th align="center">NF-KB (1SVC)</th>
</tr>
</thead>
<tbody valign="top">
<tr>
<td align="center">26</td>
<td align="center">&#x2212;9.148</td>
<td align="center">&#x2212;7.048</td>
<td align="center">&#x2212;4.90</td>
<td align="center">&#x2212;3.504</td>
</tr>
<tr>
<td align="center">27</td>
<td align="center">&#x2212;9.116</td>
<td align="center">&#x2212;6.945</td>
<td align="center">&#x2212;4.769</td>
<td align="center">&#x2212;4.199</td>
</tr>
<tr>
<td align="center">28</td>
<td align="center">&#x2212;7.452</td>
<td align="center">&#x2212;6.932</td>
<td align="center">NB</td>
<td align="center">&#x2212;3.976</td>
</tr>
<tr>
<td align="center">29</td>
<td align="center">&#x2212;7.529</td>
<td align="center">&#x2212;7.055</td>
<td align="center">&#x2212;4.006</td>
<td align="center">&#x2212;3.736</td>
</tr>
<tr>
<td align="center">
<bold>30</bold>
</td>
<td align="center">
<bold>&#x2212;10.170</bold>
</td>
<td align="center">&#x2212;6.966</td>
<td align="center">
<bold>&#x2212;5.285</bold>
</td>
<td align="center">
<bold>&#x2212;4.507</bold>
</td>
</tr>
<tr>
<td align="center">31</td>
<td align="center">&#x2212;7.771</td>
<td align="center">
<bold>&#x2212;7.516</bold>
</td>
<td align="center">&#x2212;3.936</td>
<td align="center">&#x2212;3.608</td>
</tr>
<tr>
<td align="center">32</td>
<td align="center">&#x2212;9.527</td>
<td align="center">&#x2212;7.074</td>
<td align="center">&#x2212;5.219</td>
<td align="center">&#x2212;4.429</td>
</tr>
<tr>
<td align="center">33</td>
<td align="center">&#x2212;7.086</td>
<td align="center">&#x2212;6.913</td>
<td align="center">&#x2212;5.284</td>
<td align="center">&#x2212;4.879</td>
</tr>
<tr>
<td align="center">34</td>
<td align="center">&#x2212;9.649</td>
<td align="center">&#x2212;7.491</td>
<td align="center">&#x2212;5.007</td>
<td align="center">&#x2212;4.324</td>
</tr>
<tr>
<td align="center">35</td>
<td align="center">&#x2212;7.779</td>
<td align="center">&#x2212;6.867</td>
<td align="center">&#x2212;5.154</td>
<td align="center">&#x2212;3.257</td>
</tr>
<tr>
<td align="center">36</td>
<td align="center">&#x2212;9.719</td>
<td align="center">&#x2212;7.014</td>
<td align="center">&#x2212;4.815</td>
<td align="center">&#x2212;4.003</td>
</tr>
<tr>
<td align="center">37</td>
<td align="center">&#x2212;7.508</td>
<td align="center">&#x2212;6.704</td>
<td align="center">&#x2212;4.878</td>
<td align="center">&#x2212;3.192</td>
</tr>
<tr>
<td align="center">Tamoxifen</td>
<td align="center">&#x2212;6.809</td>
<td align="center">&#x2212;6.544</td>
<td align="center">&#x2212;4.987</td>
<td align="center">&#x2212;3.162</td>
</tr>
</tbody>
</table>
<table-wrap-foot>
<fn>
<p>The bold values represent the IC<sub>50</sub> values of compounds showing significant anti-cancer activity.</p>
</fn>
</table-wrap-foot>
</table-wrap>
<fig id="F9" position="float">
<label>FIGURE 9</label>
<caption>
<p>Two-dimensional (2D) views of molecular docking: <bold>(A)</bold> molecular interactions of compound <bold>30</bold> within the pockets of the TNF-&#x3b1; target, <bold>(B)</bold> molecular interactions of compound <bold>31</bold> within the pockets of the JNK target, <bold>(C)</bold> molecular interactions of <bold>30</bold> within the pockets of the MAPK target, and <bold>(D)</bold> molecular interactions of compound <bold>30</bold> within the pockets of the NF-kB target.</p>
</caption>
<graphic xlink:href="fphar-14-1231450-g009.tif"/>
</fig>
<fig id="F10" position="float">
<label>FIGURE 10</label>
<caption>
<p>Two-dimensional (2D) views of molecular docking: <bold>(A)</bold> molecular interactions of tamoxifen within the pockets of the TNF-&#x3b1; target, <bold>(B)</bold> molecular interactions of tamoxifen within the pockets of the JNK target, <bold>(C)</bold> molecular interactions of tamoxifen within the pockets of the MAPK target, and <bold>(D)</bold> molecular interactions of tamoxifen within the pockets of the NF-kB target.</p>
</caption>
<graphic xlink:href="fphar-14-1231450-g010.tif"/>
</fig>
</sec>
<sec id="s5">
<title>5 Analysis of molecular dynamic simulation</title>
<p>After the analysis of the <italic>in vitro</italic> and docking studies, we found that compound <bold>30</bold>, as the most active derivative of neo-tanshinlactone, inhibited the cell proliferation of cancer cells via the suppression of the TNF-&#x3b1;, MAPK, and Nf-kB signaling pathways. Because of the highest binding, we performed MD simulation on compound <bold>30</bold> to study the stability within binding pockets of TNF-&#x3b1; target protein. A 100-ns trajectory was used to extract out RMSD, RMSF, RyG, and the number of hydrogen bonds of the ligand&#x2013;protein complex by applying the OPLS3 force field in the molecular system. In this experiment, we found that the RMSD value of the ligand varies from 0.512&#xa0;&#xc5; to 2.010&#xa0;&#xc5; (<xref ref-type="table" rid="T3">Table 3A</xref>) and it exhibited the conformational rotation in the active site of the protein. The RMSD value of the protein varies from 1.162&#xa0;&#xc5; to 2.402&#xa0;&#xc5; (<xref ref-type="table" rid="T3">Table 3</xref>). Initially, it showed an RMSD value 2.402 for 20&#xa0;ns time and then attained the equilibrium throughout the simulation. The RMSF value of C&#x3b1; protein deviated from 0.363&#xa0;&#xc5; to 3.987&#xa0;&#xc5; (<xref ref-type="table" rid="T3">Table 3A</xref>), but the residue Asn39 from the chain E fluctuated to 3.987&#xa0;&#xc5;, which is attributed to the stability for the whole simulation (<xref ref-type="bibr" rid="B11">Khan et al., 2022</xref>). In order to optimize the ligand properties, <bold>30</bold> was found to deviate up to 18.30&#xa0;ns, which had shown RMSD values in the range of 0.62&#xa0;&#xc5; to 1.38&#xa0;&#xc5; and then attained equilibrium at 0.41&#xa0;&#xc5;. The rGyr value of the ligand was calculated from 4.295&#xa0;&#xc5; to 4.850&#xa0;&#xc5;, followed by the achievement of the equilibrium point at 4.5&#xa0;&#xc5;. Similarly, MolSA, SASA, and PSA were computed for the ranges 369.444 &#xc5;<sup>2</sup>&#x2013;393.097 &#xc5;<sup>2</sup>, 0.000 &#xc5;<sup>2</sup>&#x2013;11.171 &#xc5;<sup>2</sup>, and 118.929 &#xc5;<sup>2</sup>&#x2013;146.046 &#xc5;<sup>2</sup>. As shown in <xref ref-type="fig" rid="F11">Figure 11</xref>, these properties of compound <bold>30</bold> showed that it remains stable throughout the MD simulation. The protein&#x2013;ligand interactions of the stable <bold>30</bold>-TNF-&#x3b1; complex were analyzed by a histogram, as shown in <xref ref-type="fig" rid="F11">Figure 11F</xref>. The protein&#x2013;ligand interactions were distinguished by including hydrogen, ionic, and hydrophobic bonds, and water bridges. We observed that compound <bold>30</bold> showed five hydrogen bonds with chain D: Tyr151, chain E: Gln61, chain E: Gly122, chain E: Tyr151, and chain F: Gly122 amino acids of the TNF-&#x3b1; target (<xref ref-type="table" rid="T4">Table 4</xref>). On the other hand, throughout the MD simulation, it formed a very stable intermolecular hydrogen bond with chain E: Tyr151, which contributed to more than 99% stability of the compound <bold>30</bold>-TNF-&#x3b1; complex. Despite the hydrogen bonds, compound <bold>30</bold> also showed 14 hydrophobic interactions with chain D: Leu57, chain D: Tyr59, chain D: Tyr119, chain D: Tyr151, chain D: Ile155, chain E: Leu57, chain E: Tyr59, chain E: Tyr119, chain E: Val123, chain F: Leu57, chain F: Tyr59, chain F: Tyr119, chain F: Val123, and chain F: Ile155 residues (<xref ref-type="table" rid="T3">Table 3B</xref>) (<xref ref-type="bibr" rid="B1">Abdalla et al., 2021</xref>; <xref ref-type="bibr" rid="B12">Kumar et al., 2022</xref>).</p>
<table-wrap id="T3" position="float">
<label>TABLE 3</label>
<caption>
<p>A) MD simulation parameters of the 30-TNF-&#x3b1; complex and B) ligand interaction with amino acids of TNF-&#x3b1; (PDB: 6X81.</p>
</caption>
<table>
<thead valign="top">
<tr>
<td align="center">
<bold>A</bold>
</td>
<td align="left">
<bold>Parameter</bold>
</td>
<td align="center">
<bold>Target receptor</bold>
</td>
</tr>
</thead>
<tbody valign="top">
<tr>
<td rowspan="7" align="center"/>
<td align="center">RMSD of the ligand (&#xc5;)</td>
<td align="center">0.512&#x2013;2.010</td>
</tr>
<tr>
<td align="center">RMSD of C&#x3b1; (&#xc5;)</td>
<td align="center">1.162&#x2013;2.402</td>
</tr>
<tr>
<td align="center">RMSF of C&#x3b1; protein (&#xc5;)</td>
<td align="center">0.363&#x2013;3.987</td>
</tr>
<tr>
<td align="center">rGyr (&#xc5;<sup>2</sup>)</td>
<td align="center">4.295&#x2013;4.850</td>
</tr>
<tr>
<td align="center">MolSA (&#xc5;<sup>2</sup>)</td>
<td align="center">369.444&#x2013;393.097</td>
</tr>
<tr>
<td align="center">SASA (&#xc5;<sup>2</sup>)</td>
<td align="center">0.000&#x2013;11.171</td>
</tr>
<tr>
<td align="center">PSA (&#xc5;<sup>2</sup>)</td>
<td align="center">118.929&#x2013;146.046</td>
</tr>
</tbody>
</table>
<table>
<thead valign="top">
<tr>
<td align="center">
<bold>B</bold>
</td>
<td align="left"/>
<td align="left"/>
</tr>
</thead>
<tbody valign="top">
<tr>
<td align="left"/>
<td align="center">H-bonds</td>
<td align="center">D: Tyr151, E: Gln61, E: Gly122, E: Tyr151, and F: Gly122</td>
</tr>
<tr>
<td align="left"/>
<td align="center">Hydrophobic bonds</td>
<td align="center">D: Leu57, D: Tyr59, D: Tyr119, D: Tyr151, D: Ile155, E: Leu57, E: Tyr59, E: Tyr119, E: Val123, F: Leu57, F: Tyr59, F: Tyr119, F: Val123, and F: Ile155</td>
</tr>
</tbody>
</table>
</table-wrap>
<fig id="F11" position="float">
<label>FIGURE 11</label>
<caption>
<p>
<bold>(A)</bold> RMSD of compound 30 (red) and TNF-&#x3b1; (gray), <bold>(B)</bold> RMSF of TNF-&#x3b1;, <bold>(C)</bold> contact of compound 30 with residues, <bold>(D)</bold> properties of the ligand, <bold>(E)</bold> interactions of compound 30 with residues via the bar chart, and <bold>(F)</bold> histogram of the no. of contacts between the ligand and amino acids of TNF-&#x3b1;.</p>
</caption>
<graphic xlink:href="fphar-14-1231450-g011.tif"/>
</fig>
<table-wrap id="T4" position="float">
<label>TABLE 4</label>
<caption>
<p>Pharmacological parameters of compounds 26&#x2013;37.</p>
</caption>
<table>
<thead valign="top">
<tr>
<th align="center">Parameter</th>
<th align="center">26</th>
<th align="center">27</th>
<th align="center">28</th>
<th align="center">29</th>
<th align="center">30</th>
<th align="center">31</th>
<th align="center">32</th>
<th align="center">33</th>
<th align="center">34</th>
<th align="center">35</th>
<th align="center">36</th>
<th align="center">37</th>
</tr>
</thead>
<tbody valign="top">
<tr>
<td align="center">
<bold>MW</bold>
</td>
<td align="center">386.4</td>
<td align="center">356.3</td>
<td align="center">386.4</td>
<td align="center">356.3</td>
<td align="center">416.4</td>
<td align="center">416.4</td>
<td align="center">326.3</td>
<td align="center">446.4</td>
<td align="center">360.7</td>
<td align="center">390.8</td>
<td align="center">395.20</td>
<td align="center">425.26</td>
</tr>
<tr>
<td align="center">
<bold>HBD</bold>
</td>
<td align="center">-</td>
<td align="center">-</td>
<td align="center">-</td>
<td align="center">-</td>
<td align="center">-</td>
<td align="center">-</td>
<td align="center">-</td>
<td align="center">-</td>
<td align="center">-</td>
<td align="center">-</td>
<td align="center">-</td>
<td align="center">-</td>
</tr>
<tr>
<td align="center">
<bold>HBA</bold>
</td>
<td align="center">6</td>
<td align="center">5</td>
<td align="center">6</td>
<td align="center">5</td>
<td align="center">6</td>
<td align="center">6</td>
<td align="center">4</td>
<td align="center">7</td>
<td align="center">4</td>
<td align="center">5</td>
<td align="center">4</td>
<td align="center">5</td>
</tr>
<tr>
<td align="center">
<bold>PSA</bold>
</td>
<td align="center">82.53</td>
<td align="center">74.41</td>
<td align="center">81.24</td>
<td align="center">73.06</td>
<td align="center">89.38</td>
<td align="center">89.49</td>
<td align="center">66.20</td>
<td align="center">96.44</td>
<td align="center">66.20</td>
<td align="center">73.06</td>
<td align="center">66.22</td>
<td align="center">73.07</td>
</tr>
<tr>
<td align="center">
<bold>LogP</bold>
</td>
<td align="center">3.85</td>
<td align="center">3.78</td>
<td align="center">3.90</td>
<td align="center">3.84</td>
<td align="center">3.97</td>
<td align="center">4.01</td>
<td align="center">3.72</td>
<td align="center">4.12</td>
<td align="center">4.23</td>
<td align="center">4.34</td>
<td align="center">4.67</td>
<td align="center">4.78</td>
</tr>
<tr>
<td align="center">
<bold>LogS</bold>
</td>
<td align="center">&#x2212;5.07</td>
<td align="center">&#x2212;4.88</td>
<td align="center">&#x2212;5.16</td>
<td align="center">&#x2212;5.00</td>
<td align="center">&#x2212;5.32</td>
<td align="center">&#x2212;5.28</td>
<td align="center">&#x2212;4.74</td>
<td align="center">&#x2212;5.57</td>
<td align="center">&#x2212;5.51</td>
<td align="center">&#x2212;5.77</td>
<td align="center">&#x2212;6.15</td>
<td align="center">&#x2212;6.41</td>
</tr>
<tr>
<td align="center">
<bold>Caco cell</bold>
</td>
<td align="center">785.81</td>
<td align="center">784.88</td>
<td align="center">785.84</td>
<td align="center">786.10</td>
<td align="center">786.69</td>
<td align="center">786.00</td>
<td align="center">785.49</td>
<td align="center">786.42</td>
<td align="center">785.47</td>
<td align="center">786.08</td>
<td align="center">784.31</td>
<td align="center">784.94</td>
</tr>
<tr>
<td align="center">
<bold>logBB</bold>
</td>
<td align="center">&#x2212;1.01</td>
<td align="center">&#x2212;0.91</td>
<td align="center">&#x2212;1.01</td>
<td align="center">&#x2212;0.92</td>
<td align="center">&#x2212;1.11</td>
<td align="center">&#x2212;1.09</td>
<td align="center">&#x2212;0.82</td>
<td align="center">&#x2212;1.20</td>
<td align="center">&#x2212;0.67</td>
<td align="center">&#x2212;0.77</td>
<td align="center">&#x2212;0.55</td>
<td align="center">&#x2212;0.65</td>
</tr>
<tr>
<td align="center">
<bold>MDCK cell</bold>
</td>
<td align="center">381.24</td>
<td align="center">380.75</td>
<td align="center">381.25</td>
<td align="center">381.39</td>
<td align="center">381.70</td>
<td align="center">381.34</td>
<td align="center">381.07</td>
<td align="center">381.56</td>
<td align="center">939.63</td>
<td align="center">940.41</td>
<td align="center">1956.63</td>
<td align="center">1958.24</td>
</tr>
<tr>
<td align="center">
<bold>HSA</bold>
</td>
<td align="center">0.249</td>
<td align="center">0.27</td>
<td align="center">0.26</td>
<td align="center">0.29</td>
<td align="center">0.24</td>
<td align="center">0.26</td>
<td align="center">0.29</td>
<td align="center">0.25</td>
<td align="center">0.42</td>
<td align="center">0.41</td>
<td align="center">0.54</td>
<td align="center">0.53</td>
</tr>
<tr>
<td align="center">
<bold>HOA</bold>
</td>
<td align="center">3</td>
<td align="center">3</td>
<td align="center">3</td>
<td align="center">3</td>
<td align="center">3</td>
<td align="center">3</td>
<td align="center">3</td>
<td align="center">3</td>
<td align="center">3</td>
<td align="center">3</td>
<td align="center">3</td>
<td align="center">3</td>
</tr>
<tr>
<td align="center">
<bold>%HOA</bold>
</td>
<td align="center">100</td>
<td align="center">100</td>
<td align="center">100</td>
<td align="center">100</td>
<td align="center">100</td>
<td align="center">100</td>
<td align="center">100</td>
<td align="center">100</td>
<td align="center">100</td>
<td align="center">100</td>
<td align="center">100</td>
<td align="center">100</td>
</tr>
</tbody>
</table>
<table-wrap-foot>
<fn id="Tfn1">
<label>
<sup>a</sup>
</label>
<p>
<bold>MW</bold>, molecular weight (130&#x2013;725); <bold>HBD</bold>, hydrogen bond donor (0&#x2013;6); <bold>HBA</bold>, hydrogen bond acceptor (2&#x2013;20); <bold>PSA</bold>, polar surface area (7&#x2013;200&#x212b;2); <bold>LogP</bold>, lipophilicity (&#x2212;2.0&#x2013;6.5); <bold>Log S</bold>, solubility (&#x2212;6.5-0.5&#xa0;mol/dm3); <bold>Caco cell</bold>, colon cancer cell (&#x3c;25 poor and &#x3e;500 high); <bold>LogBB</bold>, brain barrier (&#x2212;3.0&#x2013;1.2); <bold>MDCK cell</bold>, Madin&#x2013;Darby canin kidney cell (&#x3c;25 poor an &#x3e;500 high); <bold>HSA</bold>, human serum albumin (&#x2212;1.5&#x2013;1.5); <bold>HOA</bold>, human oral absorption (1 for low, 2 for medium, and 3 for high); <bold>%HOA</bold>, percentage of human oral absorption.</p>
</fn>
</table-wrap-foot>
</table-wrap>
</sec>
<sec id="s6">
<title>6 Pharmacological parameters of compounds</title>
<p>Preliminary screening of the hybrid compounds showed that none of the compounds violated the rule of five (Lipinski&#x2019;s rule), and all of them showed high bioavailability. Consequently, we studied the pharmacological properties of compounds <bold>30</bold> and <bold>31</bold>, which showed the highest molecular docking score, in detail. Both the compounds exhibited 100% human oral absorption and good interactions with serum albumin 0.24 and 0.26 within the range (&#x2212;1.5 to &#x2b;1.5), respectively. Furthermore, they demonstrated high penetration capabilities with values of 786.69&#xa0;nm/s and 786.00&#xa0;nm/s against Caco, and 381.70&#xa0;nm/s and 381.34&#xa0;nm/s against MDCK cells, respectively. Moreover, compounds <bold>30</bold> and <bold>31</bold> showed a significantly improved capability to cross the blood&#x2013;brain barrier with values of &#x2212;1.11 and &#x2212;1.09, which were lower than the specified criterion from &#x2212;3.0 to 1.2 (<xref ref-type="table" rid="T4">Table 4</xref>). Considering the aforementioned results, we can say that compounds <bold>30</bold> and <bold>31</bold> have all the attributes to be potent therapeutic agents (<xref ref-type="bibr" rid="B13">Kumar et al., 2023</xref>)<bold>.</bold>
</p>
</sec>
<sec id="s7">
<title>7 Critical analysis, current study limitations, and future perspective</title>
<p>Although the aforementioned strategy enabled us to synthesize a diverse library of the target hybrid molecules, we could not synthesize coumarin&#x2013;chalcone hybrids containing phenolic rings in the chalcone motif using the HWE strategy. The synthesis of the phenolic ring containing hybrid molecules may have been possible if the Claisen&#x2013;Schmidt reaction was used instead of the present strategy. However, our efforts to couple the &#x3b2;-aryl-&#x3b2;-ketophosphonates with the 4-formyl-2H-benzo [h]chromen-2-ones to obtain the target hybrid molecules using the Claisen&#x2013;Schmidt reaction were not successful. Considering the potential usefulness of the coumarin&#x2013;chalcone hybrids as novel anti-breast cancer compounds, we are now concentrating our efforts toward finding a new synthetic protocol which will enable us to synthesize newer derivatives of the aforementioned hybrid molecules and evaluate their anti-breast cancer activity in our search for more potent and less toxic anti-breast cancer agents.</p>
</sec>
<sec sec-type="conclusion" id="s8">
<title>8 Conclusion</title>
<p>In summary, a library of 12 coumarin&#x2013;chalcone hybrid compounds, <bold>26</bold>&#x2013;<bold>37</bold>, were constructed, based on the molecular hybridization concept, via a practical and effective synthetic route which involved the HWE coupling of 4-formyl-2H-benzo [h]chromen-2-ones with phosphonic acid diethyl esters. The <italic>in vitro</italic> anti-cancer activity of the synthesized hybrid molecules was evaluated using an MTT assay, wherein they were found to exhibit potent to moderate anti-cancer activity against a panel of four cancer cell lines, including two breast cancer (MCF-7, ER &#x2b; ve and MDA-MB-231, ER-ve), one cervical cancer (HeLa), and one endometrial cancer (Ishikawa) cell lines. Among these, molecules <bold>30</bold> and <bold>31</bold> were found to be the most potent, with compound <bold>30</bold> demonstrating superior activity against both ER &#x2b; ve (IC<sub>50</sub> &#x3d; 6.8&#xa0;&#xb5;M, MCF-7) and ER-ve (IC<sub>50</sub> &#x3d; 8.5&#xa0;&#xb5;M, MDA-MB-231) breast cancer cell lines as compared to the standard drug tamoxifen. The toxicity of the molecules, <bold>26</bold>&#x2013;<bold>37</bold>, was also evaluated on the normal human embryonic kidney cell line HEK-293, and interestingly, none of the screened molecules exhibited any toxicity against normal HEK-293 cells. Compound <bold>30</bold> also demonstrated a strong binding affinity with the tumor necrosis factor &#x3b1; (TNF-&#x3b1;) in molecular docking studies. This is significant because TNF&#x3b1; is associated with MCF-7 cancer cell lines. Virtual ADMET studies validated the compliance of hybrid compounds <bold>30</bold> and <bold>31</bold> with Lipinski&#x2019;s rule. Moreover, they exhibited high bioavailability, excellent oral absorption, favorable albumin interactions, strong penetration capabilities, and improved blood&#x2013;brain barrier crossing, indicating their potential as potent therapeutic agents. Thus, compound <bold>30</bold> could be considered a potential anti-breast cancer lead molecule, possibly by targeting TNF&#x3b1;.</p>
</sec>
<sec id="s9">
<title>9 Experiments</title>
<sec id="s9-1">
<title>9.1 Chemistry</title>
<p>All the chemicals were procured from Across Organics and Sigma-Aldrich, and were used without further purification. The IR spectra of the compounds were recorded using a Perkin&#x2013;Elmer Spectrum GX FTIR spectrometer. <sup>1</sup>H NMR and <sup>13</sup>C NMR spectra were recorded using the Bruker DRX-300 (300&#xa0;MHz for <sup>1</sup>H and at 75&#xa0;MHz for <sup>13</sup>C) or DPX-200 (at 50&#xa0;MHz for <sup>13</sup>C) spectrometer using CDCl<sub>3</sub>, DMSO-<italic>d</italic>
<sub>6</sub>, or TFA-d<sub>1</sub> (see the Supporting Information). Chemical shifts (&#x3b4;) are reported in parts per million (ppm), using TMS as an internal standard. ESI&#x2013;MS spectra were recorded using an LCQ advantage ion-trap mass spectrometer (Finnigan Thermo Fisher Scientific), and high-resolution mass spectra (ESI&#x2013;HRMS) were recorded using an Agilent 6520 ESI-QTOP mass spectrometer.</p>
<sec id="s9-1-1">
<title>9.1.1 General procedure for the synthesis of 2-bromo-1-(aryl) ethan-1-ones (7&#x2013;12)</title>
<p>A solution of bromine (7.50 mmol; 1.0 equiv), dissolved in Et<sub>2</sub>O (15&#xa0;mL), was added to the stirred solution of the respective substituted acetophenones (7.5&#xa0;mmol) in Et<sub>2</sub>O (15&#xa0;mL) in a 50-mL round bottom flask at 0&#xb0;C, and the mixture was stirred for 2&#xa0;h at room temperature. After the completion of the reaction, it was quenched with the saturated NaHCO<sub>3</sub> solution (100&#xa0;mL) and extracted with Et<sub>2</sub>O (3 &#xd7; 40&#xa0;ml). The combined organic layers were dried over anhydrous Na<sub>2</sub>SO<sub>4</sub> and concentrated <italic>in vacuo</italic> to obtain the crude mixture which was subsequently crystallized from EtOH to obtain the pure compounds <bold>9</bold> and <bold>10</bold>. Compounds <bold>7</bold>, <bold>8</bold>, <bold>11</bold>, and <bold>12</bold>, on the other hand, are commercially available.<list list-type="simple">
<list-item>
<p>
<bold>2-Bromo-1-(3,5-dimethoxyphenyl)ethan-1-one (9)</bold>: white crystal (87%); <sup>1</sup>H NMR (400&#xa0;MHz; CDCl<sub>3</sub>), 7.24 (d, <italic>J</italic> &#x3d; 2.6 Hz, 2H), 6.78 (d, <italic>J</italic> &#x3d; 2.4 Hz, 1H), 4.79 (s, 2H), and 3.89 (s, 6H).</p>
</list-item>
<list-item>
<p>
<bold>2-Bromo-1-(3,4,5-trimethoxyphenyl)ethan-1-one (10)</bold>: white crystals (85%); <sup>1</sup>H NMR (400&#xa0;MHz; CDCl<sub>3</sub>), 7.18 (s, 2H), 4.37 (s, 2H), 3.88 (s, 3H), and 3.84 (s, 6H).</p>
</list-item>
</list>
</p>
</sec>
<sec id="s9-1-2">
<title>9.1.2 General procedure for the synthesis of diethyl 2-oxo-2-arylethylphosphonates (13&#x2013;18)</title>
<p>Respective 2-bromo-1-(aryl)-ethan-1-ones (<bold>7&#x2013;12</bold>, 5&#xa0;mmol) and triethylphoshphite (40&#xa0;mmol) were dissolved in acetonitrile (10&#xa0;mL) using a round bottom flask and heated to 80&#xb0;C for 2&#xa0;h. After completion of the reaction, DCM (15&#xa0;mL) and water (30&#xa0;mL) were added to the reaction mixture, and it was extracted with DCM (3 &#xd7; 40&#xa0;mL). The combined organic layers were dried using Na<sub>2</sub>SO<sub>4</sub> and concentrated <italic>in vacuo</italic>. The crude residue so obtained was purified through column chromatography to yield pure phosphonates (<bold>13&#x2013;18</bold>). The analytical data on the phosphonates were found to be in agreement with those reported in the literature (<xref ref-type="bibr" rid="B4">Debrouwer et al., 2013</xref>; <xref ref-type="bibr" rid="B5">Dunny et al., 2013</xref>).</p>
<p>
<bold>Diethyl (2-oxo-2-phenylethyl)phosphonate (13)</bold>: viscous oil (82%); <sup>1</sup>H NMR (400&#xa0;MHz, CDCl<sub>3</sub>): <italic>&#x3b4;</italic> &#x3d; 8.04 (d, <italic>J</italic> &#x3d; 8.2 Hz, 2H), 7.58 (t, <italic>J</italic> &#x3d; 8.2 Hz, 1H), 7.49 (t, <italic>J</italic> &#x3d; 8.2 Hz, 2H), 4.1&#x2013;4.15 (m, 4H), 3.67 (d, <italic>J</italic> &#x3d; 23.1 Hz, 2H), and 1.25 (t, <italic>J</italic> &#x3d; 7.2 Hz, 6H); <sup>13</sup>C NMR (75&#xa0;MHz, CDCl<sub>3</sub>): <italic>&#x3b4;</italic> &#x3d; 192.0 (d, <italic>J</italic> &#x3d; 6.7&#xa0;Hz), 137.2, 134.4, 130.0, 129.4, 62.6 (d, <italic>J</italic> &#x3d; 6.6&#xa0;Hz), 38.5 (d, <italic>J</italic> &#x3d; 129.1&#xa0;Hz), and 16.6 (d, <italic>J</italic> &#x3d; 6.2&#xa0;Hz); ESI&#x2013;MS (m/z): 256; found 257 [M &#x2b; H].<sup>&#x2b;</sup>
</p>
<p>
<bold>Diethyl (2-(4-methoxyphenyl)-2-oxoethyl)phosphonate (14)</bold>: viscous oil (84%); <sup>1</sup>H NMR (300&#xa0;MHz, CDCl<sub>3</sub>): <italic>&#x3b4;</italic> &#x3d; 8.01 (d, <italic>J</italic> &#x3d; 9.0 Hz, 2H), 7.54 (t, <italic>J</italic> &#x3d; 9. 0&#xa0;Hz, 1H), 7.46 (t, <italic>J</italic> &#x3d; 8.2 Hz, 2H), 4.02&#x2013;4.08 (m, 4H), 3.62 (d, <italic>J</italic> &#x3d; 22.8 Hz, 2H), and 1.24 (t, <italic>J</italic> &#x3d; 6.8 Hz, 6H); ESI&#x2013;MS (m/z): 286; found 287 [M &#x2b; H].<sup>&#x2b;</sup>
</p>
<p>
<bold>Diethyl (2-(3,5-dimethoxyphenyl)-2-oxoethyl)phosphonate (15)</bold>: viscous oil (85%); <sup>1</sup>H NMR (400&#xa0;MHz; CDCl<sub>3</sub>), 7.62 (d, <italic>J</italic> &#x3d; 2.7 Hz, 2H), 6.78 (d, <italic>J</italic> &#x3d; 2.6 Hz, 1H), 4.2&#x2013;4.10 (m, 4H), 3.89 (s, 6H), 3.64 (d, <italic>J</italic> &#x3d; 23.1 Hz, 2H), and 1.29 (t, <italic>J</italic> &#x3d; 7.2 Hz, 6H); ESI&#x2013;MS (m/z): 316; found 17 [M &#x2b; H].<sup>&#x2b;</sup>
</p>
<p>
<bold>Diethyl (2-oxo-2-(3,4,5-trimethoxyphenyl)ethyl)phosphonate (16)</bold>: viscous oil (80%) <sup>1</sup>H NMR (400&#xa0;MHz; CDCl<sub>3</sub>), 7.58 (s, 2H), 4.2&#x2013;4.12 (m, 4H), 3.89 (s, 6H), 3.87 (s, 3H), 3.62 (d, <italic>J</italic> &#x3d; 23.4 Hz, 2H), and 1.25 (t, <italic>J</italic> &#x3d; 7.1 Hz, 6H); ESI&#x2013;MS (m/z): 346; found 347 [M &#x2b; H].<sup>&#x2b;</sup>
</p>
</sec>
<sec id="s9-1-3">
<title>9.1.3 General procedure for the synthesis of benzocoumarin&#x2013;chalcone hybrids (26&#x2013;37)</title>
<p>A volume of 6&#xa0;mmol of NaOMe was added dropwise to a solution of the respective phosphonates (<bold>13&#x2013;18</bold>, 2&#xa0;mmol<bold>)</bold> in dry DMF (5&#xa0;mL) at 0&#xb0;C. The resulting mixture was stirred at the same temperature for 1&#xa0;h, followed by the dropwise addition of benzocoumarin-4-carbaldehyde (2<bold>4&#x2013;25</bold>, 2.0&#xa0;mmol) in DMF (5&#xa0;mL), and the reaction mixture was allowed to stir at room temperature for an additional 4&#xa0;h. On the completion of the reaction, the reaction mixture was quenched with ice water and allowed to stand for 2&#xa0;h. The solid that precipitated out was filtered, washed with Et<sub>2</sub>O, and crystallized from hot EtOAc to provide the desired benzocoumarin&#x2013;chalcone hybrid compounds (<bold>26&#x2013;37</bold>) as pure compounds.</p>
<p>
<bold>(E)-4-(3-(3,5-Dimethoxyphenyl)-3-oxoprop-1-en-1-yl)-2H-benzo[h]chromen-2-one (26)</bold>: light yellow solid (95%); mp272&#x2013;273&#xb0;C; Anal. (%) for C<sub>24</sub>H<sub>18</sub>O<sub>5</sub>: Calcd., C, 74.60; H, 4.70; found, C, 74.78; H, 4.69; IR (KBr) &#x3bd;/cm<sup>-1</sup>; <sup>1</sup>H NMR (300&#xa0;MHz, CDCl<sub>3</sub>&#x2b; DMSO-<italic>d</italic>
<sub>6</sub>) <italic>&#x3b4;</italic> 8.54 (brs, 1H), 8.12 (d, <italic>J</italic> &#x3d; 15.2 Hz, 1H), 7.92 (brs, 1H), 7.81&#x2013;7.76 (m, 3H), 7.69&#x2013;7.67 (m, 2H), 7.22 (s, 2H), 6.89 (s, 1H), 6.73 (s, 1H), and 3.88 (s, 6H); <sup>13</sup>C NMR (CDCl<sub>3,</sub> 75&#xa0;MHz) <italic>&#x3b4;</italic> 188.4, 161.1, 160.6, 151.2, 149.8, 138.8, 136.8, 135.0, 130.0, 129.1, 127.7, 124.6, 123.2, 122.7, 120.1, 112.4, 106.5, 106.1, and 55.7; ESI&#x2013;MS: (m/z); 386, found [M &#x2b; H ]<sup>&#x2b;</sup> 387; HRMS-ESI: C<sub>24</sub>H<sub>19</sub>O<sub>5</sub> [M &#x2b; H]<sup>&#x2b;</sup>calcd 387.1232, found 387.1343.</p>
<p>
<bold>(E)-4-(3-(4-Methoxyphenyl)-3-oxoprop-1-enyl)-2<italic>H</italic>-benzo[<italic>h</italic>]chromen-2-one (27)</bold>: light yellow solid (93%); mp 255&#x2013;252&#xb0;C; IR (KBr) 3040, 1704, 1574, 1465, 1235, 1120, and 812 &#x3bd;/cm<sup>-1</sup>, <sup>1</sup>H NMR (300&#xa0;MHz, CDCl<sub>3</sub>) <italic>&#x3b4;</italic> 8.64&#x2013;8.61 (m, 1H), 8.19&#x2013;8.08 (m, 3H), 7.92&#x2013;7.91 (m, 1H), 7.77&#x2013;7.68 (m, 5H), 7.05 (d, <italic>J</italic> &#x3d; 8.7 Hz, 2H), 6.78 (s, 1H), and 3.94 (s, 3H); <sup>13</sup>C NMR (CDCl<sub>3,</sub> 75&#xa0;MHz) <italic>&#x3b4;</italic> 186.9, 164.6, 160.7, 151.1, 150.0, 135.9, 135.0, 131.2, 129.9, 129.0, 127.7,127.4, 124.6, 123.2, 122.7, 120.2, 114.2, 113.5,112.2, and 55.6; ESI&#x2013;MS: (m/z); 356, found [M &#x2b; H ]<sup>&#x2b;</sup> 357; HRMS-ESI: C<sub>23</sub>H<sub>17</sub>O<sub>4</sub> [M &#x2b; H]<sup>&#x2b;</sup>calcd 357.1127, found 357.1132.</p>
<p>
<bold>(E)-7-Methoxy-4-(3-(4-methoxyphenyl)-3-oxoprop-1-enyl)-2<italic>H</italic>-benzo[<italic>h</italic>]chromen-2-one (28)</bold>: light yellow solid (92%); mp 236&#x2013;237&#xb0;C; Anal. (%) for C<sub>24</sub>H<sub>18</sub>O<sub>5</sub>: Calcd., C, 74.60; H, 4.70; found, C, 74.44; H, 4.75; IR (KBr) 1730, 1604, 1386, 1262, 1177, and 1052 &#x3bd;/cm<sup>-1</sup>, <sup>1</sup>H NMR (300&#xa0;MHz, TFA-<italic>d</italic>
<sub>1</sub>) <italic>&#x3b4;</italic> 8.27&#x2013;8.16 (m, 5H), 7.92 (d, <italic>J</italic> &#x3d; 15.5 Hz, 1H), 7.73 (d, <italic>J</italic> &#x3d; 8.9 Hz, 1H), 7.6 (s, 1H), 7.15&#x2013;7.13 (m, 4H), 4.06 (s, 3H), and 4.01 (s, 3H); <sup>13</sup>C NMR (TFA-<italic>d</italic>
<sub>1,</sub> 75&#xa0;MHz) <italic>&#x3b4;</italic> 165.2, 154.9, 153.3, 136.5, 132.2, 130.9, 128.6, 128.2, 127.4, 123.4, 120.4, 117.8, 116.5, 115.2, 114.3, 114.1, 112.8, 111.5, 109.6, 108.7, 55.0, and 54.6; ESI&#x2013;MS: (m/z); 386, found [M &#x2b; H ]<sup>&#x2b;</sup> 387; HRMS-ESI: C<sub>24</sub>H<sub>19</sub>O<sub>5</sub> [M &#x2b; H]<sup>&#x2b;</sup>calcd 387.1232, found 387.1338.</p>
<p>
<bold>(E)-7-Methoxy-4-(3-oxo-3-phenylprop-1-en-1-yl)-2H-benzo[h]chromen-2-one (29)</bold>: light yellow solid; yield: 92%, mp 180&#x2013;182&#xb0;C; <sup>1</sup>H NMR (300&#xa0;MHz, CDCl<sub>3</sub>) <italic>&#x3b4;</italic> 8.28&#x2013;8.24 (m, 2H), 7.89 (d, <italic>J</italic> &#x3d; 8.8 Hz, 1H), 7.77&#x2013;7.66 (m, 3H), 7.58&#x2013;7.49 (m, 4H), 7.41 (d, <italic>J</italic> &#x3d; 15.9 Hz, 1H),7.12 (d, <italic>J</italic> &#x3d; 7.7 Hz, 1H), 6.81 (s, 1H), and 4.04 (s, 3H); <sup>13</sup>C NMR (CDCl<sub>3,</sub> 75&#xa0;MHz) <italic>&#x3b4;</italic> 188.6, 162.1, 156.21, 152.2, 151.4,138.4, 136.2, 128.4, 129.1, 128.6, 127.8, 126.9, 124.8, 121.2, 119.6, 118.8, 114.6, 114.6, 110.2, 106.4, and 55.8; ESI&#x2013;MS: (m/z); 328, found [M &#x2b; H ]<sup>&#x2b;</sup> 329; HRMS-ESI: [M &#x2b; H]<sup>&#x2b;</sup> for C<sub>23</sub>H<sub>17</sub>O<sub>4</sub> calcd 357.1127, found 357.1119.</p>
<p>
<bold>(E)-4-(3-(3,5-Dimethoxyphenyl)-3-oxoprop-1-en-1-yl)-7-methoxy-2H-benzo[h]chromen-2-one (30)</bold>: light yellow solid (97%); mp 258&#x2013;259&#xb0;C; Anal. (%) for C<sub>25</sub>H<sub>20</sub>O<sub>6</sub>: Calcd., C, 72.11; H, 4.84; found, C, 72.24; H, 4.82; IR (KBr), 2952, 1728, 1668,1578, 1458,1352, and 1245 &#x3bd;/cm<sup>-1</sup>, <sup>1</sup>H NMR (300&#xa0;MHz, TFA-<italic>d</italic>
<sub>1</sub>) <italic>&#x3b4;</italic> 8.14&#x2013;8.09 (m, 3H), 7.88 (d, <italic>J</italic> &#x3d; 7.8 Hz, 1H), 7.70&#x2013;7.50 (m, 3H), 7.44 (s, 1H), 6.98 (d, <italic>J</italic> &#x3d; 8.5 Hz, 2H), 6.81(s 1H), 3.88 (s, 3H), and 3.80 (s, 6H); <sup>13</sup>C NMR (TFA-<italic>d</italic>
<sub>1,</sub> 75&#xa0;MHz) <italic>&#x3b4;</italic> 193.0, 160.1,154.8, 153.0, 150.2, 137.8, 137.5, 130.6, 128.1, 123.4, 120.4, 117.8, 116.6, 115.2, 109.9, and 55.1, ESI&#x2013;MS: (m/z); 416, found [M &#x2b; H ]<sup>&#x2b;</sup> 417; HRMS-ESI: C<sub>25</sub>H<sub>21</sub>O<sub>6</sub> [M &#x2b; H]<sup>&#x2b;</sup>calcd 417.1338, found 417.1349.</p>
<p>
<bold>(E)-4-(3-Oxo-3-(3,4,5-trimethoxyphenyl)prop-1-enyl)-2<italic>H</italic>-benzo[<italic>h</italic>]chromen-2-one (31)</bold>: light yellow solid (97%); mp 266&#x2013;267&#xb0;C; Anal. (%) for C<sub>25</sub>H<sub>20</sub>O<sub>6</sub>: Calcd., C, 72.11; H, 4.84; found, C, 72.29; H, 4.80; IR (KBr) 3064, 1709,1613, 1468, 1377, 1226, and 1078. 967 &#x3bd;/cm<sup>-1</sup>, <sup>1</sup>H NMR (300&#xa0;MHz, CDCl<sub>3</sub>) <italic>&#x3b4;</italic> 8.58&#x2013;8.55 (m, 1H), 8.16 (d, <italic>J</italic> &#x3d; 15.3 Hz, 1H), 7.90&#x2013;7.88 (m, 1H), 7.73&#x2013;7.66 (m, 5H), 7.35 (s, 2H), 6.79 (s, 1H), and 3.99 (s, 9H); <sup>13</sup>C NMR (CDCl<sub>3,</sub> 75&#xa0;MHz) <italic>&#x3b4;</italic> 187.3, 160.7, 153.3, 151.1, 149.8, 143.3, 136.5, 135.0, 132.1, 129.6, 129.1, 127.7,127.4, 124.6, 123.2, 122.6, 120.0, 113.4, 112.3, 106.2, 61.0, and 56.4; ESI&#x2013;MS: (m/z); 416, found [M &#x2b; H ]<sup>&#x2b;</sup> 417; HRMS-ESI: C<sub>25</sub>H<sub>21</sub>O<sub>6</sub> [M &#x2b; H]<sup>&#x2b;</sup>calcd 417.1338, found 417.1344.</p>
<p>
<bold>(E)-4-(3-Oxo-3-phenylprop-1-enyl)-2<italic>H</italic>-benzo[<italic>h</italic>]chromen-2-one (32)</bold>: light yellow (95%) solid; mp 245&#x2013;246&#xb0;C; Anal. (%) for C<sub>22</sub>H<sub>14</sub>O<sub>3</sub>: Calcd., C, 80.97; H, 4.32; found, C, 80.78; H, 4.36; IR (KBr) 3434, 2940, 1709, 1584, 1460, 1237, 1126, and 814 &#x3bd;/cm<sup>-1</sup>, <sup>1</sup>H NMR (300&#xa0;MHz, CDCl<sub>3</sub>) <italic>&#x3b4;</italic> 8.61&#x2013;8.59 (m, 1H), 8.20&#x2013;8.08 (m, 3H), 7.91&#x2013;7.90 (m, 1H), 7.75&#x2013;7.68 (m, 6H), 7.61&#x2013;7.56 (m, 2H), and 6.77 (s, 1H); <sup>13</sup>C NMR (CDCl<sub>3,</sub> 75&#xa0;MHz) <italic>&#x3b4;</italic> 188.7, 160.6, 151.1, 149.8, 136.9, 136.7, 135.0, 133.8, 129.9, 129.1, 128.7, 127.7, 127.4, 124.6, 123.2, 122.7, 120.1, 113.3, and 112.4; ESI&#x2013;MS: (m/z); 326, found [M &#x2b; H ]<sup>&#x2b;</sup> 327; HRMS-ESI: C<sub>22</sub>H<sub>15</sub>O<sub>3</sub> [M &#x2b; H]<sup>&#x2b;</sup>calcd 327.1021, found 327.1032.</p>
<p>
<bold>(E)-7-Methoxy-4-(3-oxo-3-(3,4,5-trimethoxyphenyl)prop-1-enyl)-2<italic>H</italic>-benzo[<italic>h</italic>] chromen-2-one (33)</bold>: light yellow solid (94%); mp &#x3e; 260&#xb0;C; Anal. (%) for C<sub>26</sub>H<sub>22</sub>O<sub>7</sub>: Calcd., C, 69.95; H, 4.97; found, C, 69.78; H, 4.96; IR (KBr) 3434, 2941, 1733, 1663,1588, 1461,1344, and 1241 &#x3bd;/cm<sup>-1</sup>, <sup>1</sup>H NMR (300&#xa0;MHz, CDCl<sub>3</sub>) <italic>&#x3b4;</italic> 8.18&#x2013;8.10 (m, 3H), 7.74&#x2013;7.67 (m, 2H), 7.60&#x2013;7.53 (m, 1H), 7.35 (s, 2H), 7.02 (d, <italic>J</italic> &#x3d; 7.7 Hz, 1H), 6.82 (s, 1H), 4.04 (s, 3H), and 3.99 (s, 9H); <sup>13</sup>C NMR (CDCl<sub>3</sub>, 75&#xa0;MHz) <italic>&#x3b4;</italic> 187.4, 161.2, 155.1, 153.3, 150.7, 150.0, 143.3, 136.5, 132.1, 129.6, 127.8, 127.0, 124.2, 119.1, 119.0, 114.4, 113.8, 112.3, 107.1, 106.2, 61.40, 56.4, and 55.7; ESI&#x2013;MS: (m/z); 446, found [M &#x2b; H ]<sup>&#x2b;</sup> 447; HRMS-ESI: [M &#x2b; H]<sup>&#x2b;</sup> C<sub>26</sub>H<sub>23</sub>O<sub>7</sub> [M &#x2b; H]<sup>&#x2b;</sup>calcd 447.1444, found 447.1448.</p>
</sec>
</sec>
<sec id="s9-2">
<title>9.2 Biology</title>
<sec id="s9-2-1">
<title>9.2.1 Cell culture</title>
<p>MCF-7, MDA-MB231, and HEK293 cell lines were purchased from ATCC (Manassas, VA, United States). Ishikawa cell lines were obtained from the European Collection of Cell Cultures. They were maintained in Dulbecco&#x2019;s modified Eagle medium (DMEM) supplemented with 10% fetal bovine serum (FBS). Cells were cultured at 37&#xb0;C and 5% CO<sub>2</sub>. Before the experiments, cells were cultured in phenol red-free DMEM supplemented with 10% charcoal stripped fetal bovine serum.</p>
</sec>
<sec id="s9-2-2">
<title>9.2.2 Cell proliferation assay (MTT assay) in cancer cell lines and normal cell lines</title>
<p>The synthesized hybrid compounds were tested for their anti-cancer activity using the MTT reduction assay on 2.5 &#xd7; 10<sup>3</sup> cells per well that were seeded in 100&#xa0;&#xb5;L DMEM supplemented with 10% FBS in each well of 96-well microculture plates. After seeding, the cells were incubated for 24&#xa0;h at 37&#xb0;C in a CO<sub>2</sub> incubator. The required concentrations of the compounds were achieved by diluting the solutions in the culture medium. The media was removed from the wells after 48&#xa0;h, and 100&#xa0;&#xb5;L of MTT (0.5&#xa0;mg/mL) was added to each well. The plates were then incubated for an additional 3&#xa0;h. After carefully removing the supernatant from each well, the formazan crystals were dissolved in 100&#xa0;&#xb5;L of DMSO. The absorbance was then recorded at a wavelength of 540&#xa0;nm (<xref ref-type="bibr" rid="B27">Saquib et al., 2021</xref>; <xref ref-type="bibr" rid="B8">Gupta et al., 2022</xref>; <xref ref-type="bibr" rid="B10">Iqbal et al., 2023</xref>)</p>
</sec>
</sec>
<sec id="s9-3">
<title>9.3 Molecular docking studies</title>
<p>Molecular docking is used to predict the possible binding abilities of ligands within the pockets of amino acid residues of target protein receptors. To find out the possible binding modes, the calculation of docking scores was carried out for all synthesized compounds, <bold>26&#x2013;37</bold>, against four&#xa0;cell proliferating proteins, namely, NF-k&#x3b2;, TNF-&#x3b1;, MAPK, and JNK, using the Glide module of Maestro version 12.6.144 (Schr&#xf6;dinger 2020&#x2013;4 LCC, New York, United States) software. The chemical structures of compounds, <bold>26</bold>&#x2013;<bold>37</bold>, were drawn using ChemDraw Professional 15.0 software, and the 2D structures were saved in the mol format (<xref ref-type="table" rid="T1">Table 1</xref>). Ligands were prepared using the LigPrep module of Maestro version 12.6.144 (Schr&#xf6;dinger 2020&#x2013;4 LCC, New York, United States) software. The minimization of all ligands corrected the bond length and angle, and generated the possible conformers by using the OPLS force field. All the feasible protonation and ionization states were itemized for each compound using Epik pH 7.0&#xb1;2.0 and then saved in the Maestro format (<xref ref-type="bibr" rid="B6">Fadaka et al., 2022</xref>). The crystal structure of protein receptors, namely, TNF-&#x3b1;, (PDB ID 6X81), JNK (1JNK), MAPK (1A9U), and NF-kB (1SVC), having the resolution of 2.81&#xa0;&#xc5;, were obtained from the RCSB PDB database (<ext-link ext-link-type="uri" xlink:href="https://www.rcsb.org/">https://www.rcsb.org/</ext-link>) and then prepared by using the protein preparation wizard module of Maestro version 12.6.144 (Schr&#xf6;dinger 2020&#x2013;4 LCC, New York, United States) software. The refinement of the protein structure was carried out by the removal of the heteroatom and water molecules, followed by the assignment of the bond order with added hydrogen atoms using the OPLS force field and minimized the receptor (<xref ref-type="bibr" rid="B23">Pattar et al., 2020</xref>). In order to identify the top-ranked potential receptor-binding sites in protein, the active sites were predicted for ligand binding to the receptor using the sitemap module of Maestro version 12.6.144 (Schr&#xf6;dinger 2020&#x2013;4 LCC, New York, United States) software (<xref ref-type="bibr" rid="B9">Halgren, 2009</xref>). The grid box was centroid over the active site of the protein, which was predicted by the sitemap with the van der Waals scaling factor of 1.0&#xa0;&#xc5;, and the partial charge cut-off was 0.25&#xa0;&#xc5; (<xref ref-type="bibr" rid="B29">Sharma et al., 2016</xref>). For molecular docking, the softened potential was considered by the van der Waal radii scaling factor of 0.80&#xa0;&#xc5; with a 0.15-&#xc5; partial charge cut-off for non-polar parts of ligands. After docking, we saved the best pose of the ligand&#x2013;protein complex based on the docking scores (<xref ref-type="bibr" rid="B2">Ansari et al., 2022</xref>).</p>
</sec>
<sec id="s9-4">
<title>9.4 Molecular dynamic simulation</title>
<p>The molecular dynamic simulation study was conducted to check the stability of the ligand&#x2013;protein complex. The MD simulation was implemented using the Desmond module of Maestro version 12.6.144 (Schr&#xf6;dinger 2020&#x2013;4 LCC, New York, United States) software. The best pose of the docked ligand&#x2013;protein complex was immersed into the TIP3P water solvent model and generated the orthorhombic boundary with the shape size of 10&#xa0;&#xc5; &#xd7; 10 &#xc5; X10 &#xc5;. The system was neutralized by Na<sup>&#x2b;</sup>/Cl<sup>&#x2212;</sup> ions at 0.15 M salt concentration, and the whole system was minimized by applying the OPLS3 force field. The MD simulation was performed in an NPT ensemble at 300&#xa0;K and 1.013&#xa0;bar pressure over the 100-ns simulation. To maintain the temperature and pressure, we used the Nose&#x2013;Hoover chain thermostat and Martyna&#x2013;Tobias&#x2013;Klein barostat method, respectively. The RESPA (reversible reference system propagator algorithm) integrator was used with time to accelerate the simulation of each 2.0&#xa0;fs step with the PME (particle&#x2013;mesh Ewald) method for the calculation of the long-range electrostatic interaction. Finally, the energy was evaluated at every 100.0&#xa0;ps interval after analyzing the simulation trajectory (<xref ref-type="bibr" rid="B2">Ansari et al., 2022</xref>).</p>
</sec>
<sec id="s9-5">
<title>9.5 Pharmacological properties</title>
<p>The pharmacological properties of <bold>26</bold>&#x2013;<bold>37</bold> compounds were assessed using the QikProp v6.8 tool of Maestro 12.6.144 (Schr&#xf6;dinger 2020&#x2013;4 LCC, New York, United States) software. The QikProp v6.8 tool analyzes a number of significant factors, such as molecular weight (MW), hydrogen bond donor (HBD), hydrogen bond acceptor (HBA), polar surface area (PSA), lipophilicity (LogP), aqueous solubility (LogS), Caco cell permeability, MSCK permeability, human serum albumin (HSA), and human oral absorption (HOA), that are useful in predicting drug-like candidate properties (<xref ref-type="bibr" rid="B21">Mohan et al., 2022</xref>)</p>
</sec>
</sec>
</body>
<back>
<sec sec-type="data-availability" id="s10">
<title>Data availability statement</title>
<p>The original contributions presented in the study are included in the article/Supplementary material; further inquiries can be directed to the corresponding authors.</p>
</sec>
<sec id="s11">
<title>Author contributions</title>
<p>NA and MS conceived and designed the synthesis, helped with performing the reactions, performed the analysis, and wrote the paper; MK and WA performed molecular docking and dynamic simulation, DA performed the analysis and helped with writing the paper; MI helped with the anti-cancer screening of the compounds and the analysis of the screening results; MK and MH conceived and designed the synthesis, helped with performing the reactions, performed the analysis, and wrote the paper. All authors contributed to the article and approved the submitted version.</p>
</sec>
<sec id="s12">
<title>Funding</title>
<p>This project was funded by the Deanship of Scientific Research (DSR) at King Abdulaziz University, Jeddah, under Grant No. (RG-5-166-38). The authors, therefore, thank the DSR for technical and financial support.</p>
</sec>
<ack>
<p>The authors are thankful to their respective institutions for technical and administrative support.</p>
</ack>
<sec sec-type="COI-statement" id="s13">
<title>Conflict of interest</title>
<p>The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.</p>
</sec>
<sec sec-type="disclaimer" id="s14">
<title>Publisher&#x2019;s note</title>
<p>All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors, and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.</p>
</sec>
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