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<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">Front. Drug. Discov.</journal-id>
<journal-title>Frontiers in Drug Discovery</journal-title>
<abbrev-journal-title abbrev-type="pubmed">Front. Drug. Discov.</abbrev-journal-title>
<issn pub-type="epub">2674-0338</issn>
<publisher>
<publisher-name>Frontiers Media S.A.</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="publisher-id">1072448</article-id>
<article-id pub-id-type="doi">10.3389/fddsv.2022.1072448</article-id>
<article-categories>
<subj-group subj-group-type="heading">
<subject>Drug Discovery</subject>
<subj-group>
<subject>Review</subject>
</subj-group>
</subj-group>
</article-categories>
<title-group>
<article-title>Coumarin-1,2,3-triazole hybrids as leading-edge anticancer agents</article-title>
<alt-title alt-title-type="left-running-head">Mishra and Upadhyay</alt-title>
<alt-title alt-title-type="right-running-head">
<ext-link ext-link-type="uri" xlink:href="https://doi.org/10.3389/fddsv.2022.1072448">10.3389/fddsv.2022.1072448</ext-link>
</alt-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname>Mishra</surname>
<given-names>Krishna N.</given-names>
</name>
<uri xlink:href="https://loop.frontiersin.org/people/2062141/overview"/>
</contrib>
<contrib contrib-type="author" corresp="yes">
<name>
<surname>Upadhyay</surname>
<given-names>Harish C.</given-names>
</name>
<xref ref-type="corresp" rid="c001">&#x2a;</xref>
<uri xlink:href="https://loop.frontiersin.org/people/1984509/overview"/>
</contrib>
</contrib-group>
<aff>
<institution>Laboratory of Chemistry</institution>, <institution>Department of Applied Sciences</institution>, <institution>Rajkiya Engineering College (Affiliated with Dr. A.P.J. Abdul Kalam Technical University Lucknow)</institution>, <addr-line>Churk</addr-line>, <country>India</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/1192146/overview">Cristina Maccallini</ext-link>, University of Studies G. d&#x27;Annunzio Chieti and Pescara, Italy</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/1986898/overview">Marwa Balaha</ext-link>, Kafrelsheikh University, Egypt</p>
<p>
<ext-link ext-link-type="uri" xlink:href="https://loop.frontiersin.org/people/974819/overview">Afzal Basha Shaik</ext-link>, Jawaharlal Nehru Technological University, India</p>
</fn>
<corresp id="c001">&#x2a;Correspondence: Harish C. Upadhyay, <email>harishcu@gmail.com</email>
</corresp>
<fn fn-type="other">
<p>This article was submitted to Anti-Cancer Drugs, a section of the journal Frontiers in Drug Discovery</p>
</fn>
</author-notes>
<pub-date pub-type="epub">
<day>06</day>
<month>12</month>
<year>2022</year>
</pub-date>
<pub-date pub-type="collection">
<year>2022</year>
</pub-date>
<volume>2</volume>
<elocation-id>1072448</elocation-id>
<history>
<date date-type="received">
<day>17</day>
<month>10</month>
<year>2022</year>
</date>
<date date-type="accepted">
<day>22</day>
<month>11</month>
<year>2022</year>
</date>
</history>
<permissions>
<copyright-statement>Copyright &#xa9; 2022 Mishra and Upadhyay.</copyright-statement>
<copyright-year>2022</copyright-year>
<copyright-holder>Mishra and Upadhyay</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>Cancer is one of the most feared and dreaded diseases across the world. In clinical practice, a variety of anticancer agents of natural, semi-synthetic and synthetic origin exist, but they suffer from side effects and drug resistance, so they are insufficient to combat the disease. Coumarins are bicyclic benzene-pyrone-fused phytomolecules with a wide range of biological effects, including powerful anticancer activity on numerous cell lines. Additionally, they serve as an adaptable synthetic scaffold and research hub for medicinal chemists. On the other hand, triazoles are nitrogen-containing heterocycles having remarkable pharmacological effects including anticancer activities. Due to a better compatibility with the human metabolic system, the synthesis of nature inspired hybrid compounds as anticancer agents for a wide range of activity and fewer side effects is at the forefront of current research. In the last decade, huge research has been published on coumarin-1,2,3-triazole hybrids showing potent anticancer activities on various types of cancer. This review offers a recent, thorough literature compilation of contemporary research on the development of hybrid compounds based on coumarin-1,2,3-triazoles as potential anticancer leads throughout the previous 10 years.</p>
</abstract>
<abstract abstract-type="graphical">
<title>Graphical Abstract</title>
<p>
<graphic xlink:href="FDDSV_fddsv-2022-1072448_wc_abs1.tif" position="anchor"/>
</p>
</abstract>
<kwd-group>
<kwd>chemotherapy</kwd>
<kwd>drug resistance</kwd>
<kwd>hybrid molecules</kwd>
<kwd>coumarin</kwd>
<kwd>triazole</kwd>
<kwd>anticancer</kwd>
<kwd>anticytotoxic</kwd>
<kwd>apoptosis</kwd>
</kwd-group>
</article-meta>
</front>
<body>
<sec id="s1">
<title>Introduction</title>
<p>Cancer is the rapid creation of abnormal cells in the body, growing beyond their usual boundaries (<xref ref-type="bibr" rid="B8">Cooper and Hausman, 2007a</xref>; <xref ref-type="bibr" rid="B9">2007b</xref>). The cancer cells can spread to other organs by invading the adjoining parts of the body, the process is called metastasis, which may be considered as the primary cause of death due to cancer (<xref ref-type="bibr" rid="B9">Cooper and Hausman, 2007b</xref>). Most of the cancer occurs in the form of malignant tumors with a few notable exceptions, such as leukemia (<xref ref-type="bibr" rid="B8">Cooper and Hausman, 2007a</xref>; <xref ref-type="bibr" rid="B9">2007b</xref>). The common type of cancer, known as &#x201c;sarcoma&#x201d;, which affects the epithelial cells lining internal organs or the skin, includes lung cancer, skin cancer, pancreatic cancer, ovarian cancer, etc. The other forms of cancer are lymphoma, melanoma, myeloma and mixed type cancers (<xref ref-type="bibr" rid="B8">Cooper and Hausman, 2007a</xref>; <xref ref-type="bibr" rid="B41">New Global Cancer Data: GLOBOCAN, 2018</xref>). Across the world, the lung, prostate, colorectal, stomach and liver cancer are the most common types of cancer in men, whereas, breast, colorectal, lung, cervical and thyroid cancer are the most common among women (<xref ref-type="bibr" rid="B7">Bray et al., 2018</xref>; <xref ref-type="bibr" rid="B72">WHO, 2021</xref>). Out of total deaths across the globe in 2018, the one-sixth, accounting for an estimated 9.6 million were due to cancer (<xref ref-type="bibr" rid="B7">Bray et al., 2018</xref>). In United States, the projected new cancer cases and cancer deaths are 1,918,030 and 609,360 respectively, for the year 2022; specifying 350 deaths per day from lung cancer, the leading cause of cancer death (<xref ref-type="bibr" rid="B54">Siegel et al., 2022</xref>). In 2040, it is anticipated that there would be 29.5 million new instances of cancer per year and 16.4 million cancer-related deaths (<xref ref-type="bibr" rid="B40">National Cancer Institute, 2021</xref>). The common methods of cancer treatment are chemotherapy, radiation therapy or surgery with chemotherapy (<xref ref-type="bibr" rid="B51">Schirrmacher, 1985</xref>; <xref ref-type="bibr" rid="B81">Zugazagoitia et al., 2016</xref>). One or more ways of combinatorial treatment may be applied simultaneously based on the level of advancement in cancer. Some other therapies are hormone therapy, hyperthermia, immunotherapy, photodynamic therapy, stem cell transplant, surgery targeted therapy (<xref ref-type="bibr" rid="B51">Schirrmacher, 1985</xref>; <xref ref-type="bibr" rid="B81">Zugazagoitia et al., 2016</xref>). However, still the chemotherapy is the essential mode of cancer treatment. Although the burden of cancer is increasing globally, it is having a nearly unaffordable impact on the medical infrastructure in low- and middle-income nations, which is why the death rate from cancer is so high (<xref ref-type="bibr" rid="B61">Sung et al., 2021</xref>; <xref ref-type="bibr" rid="B54">Siegel et al., 2022</xref>).</p>
<p>Although there are many anticancer medications in use, the number of adverse effects and the emergence of resistance have rendered the current anticancer medications ineffective (<xref ref-type="bibr" rid="B41">New Global Cancer Data: GLOBOCAN, 2018</xref>). New chemotherapeutic drugs are always required for the treatment of diverse cancer kinds. The drugs based on natural products have always been a great choice for a medicinal chemist for the treatment of a variety of diseases and illness because of their syncing with human metabolic system (<xref ref-type="bibr" rid="B16">Dwivedi et al., 2014</xref>; <xref ref-type="bibr" rid="B50">Saxena et al., 2018</xref>; <xref ref-type="bibr" rid="B68">Upadhyay, 2019</xref>). More than half of the drugs approved by United States Food and Drug Administration (USFDA) are either natural product or their prototype in form of semi-synthetic or synthetic drug (<xref ref-type="bibr" rid="B66">Upadhyay et al., 2014</xref>, <xref ref-type="bibr" rid="B69">2020</xref>; <xref ref-type="bibr" rid="B43">Newman and Cragg, 2020</xref>; <xref ref-type="bibr" rid="B4">Atanasov et al., 2021</xref>). Only 37% of the 974 small molecules that were developed as novel anticancer drugs between 1981 and 2006 were actually synthetic; the remainder were either naturally occurring, their derivatives, or modelled after natural products (<xref ref-type="bibr" rid="B10">Cragg and Newman, 2009</xref>). Of the 175 small molecules used as anticancer medications between the years of the 1940s and 2010, 131 (74.8%) are non-synthetic and 85 (48.6%) are truly either natural compounds or directly derived from them (<xref ref-type="bibr" rid="B42">Newman and Cragg, 2012</xref>). In this way, natural ingredients have served as medications for practically all prevalent illnesses and disabilities either directly or indirectly, and the process is still ongoing (<xref ref-type="bibr" rid="B10">Cragg and Newman, 2009</xref>; <xref ref-type="bibr" rid="B42">Newman and Cragg, 2012</xref>). With improvements in anticancer drug development and discovery over the past few decades, the FDA has approved more than 100 drugs for cancer treatments (<xref ref-type="bibr" rid="B5">Blagosklonny, 2004</xref>; <xref ref-type="bibr" rid="B27">Kinch, 2014</xref>). Currently available plant-based anticancer drugs fall into four categories: vinca alkaloids (vinblastine, vincristine, and vindesine), epipodophyllotoxins (etoposide and teniposide), taxanes (paclitaxel and docetaxel), and camptothecin derivatives (camptotecin and irinotecan) (<xref ref-type="bibr" rid="B11">Desai et al., 2008</xref>; <xref ref-type="bibr" rid="B78">Zaid et al., 2017</xref>; <xref ref-type="bibr" rid="B77">Yedjou et al., 2019</xref>). Based on their modes of action, these drugs can be broadly divided into two basic categories: cytotoxic and targeted agents (<xref ref-type="bibr" rid="B35">Masui et al., 2013</xref>; <xref ref-type="bibr" rid="B73">Winkler et al., 2014</xref>).</p>
<p>Both coumarin and 1,2,3-triazole moieties are reported to possess a diverse range of pharmacological activities including anticancer, anti-HIV, antimalarial, anti-tubercular, anti-microbial, anti-inflammatory, antioxidant, antiviral, and diabetic activities (<xref ref-type="bibr" rid="B60">Stefanachi et al., 2018</xref>; <xref ref-type="bibr" rid="B6">Bozorov et al., 2019</xref>). In the past 10&#xa0;years, many biologically active pharmacophores with coumarin-1,2,3-triazole moiety have been created by synthetic chemists in an effort to obtain multi-targeted single molecules (<xref ref-type="bibr" rid="B18">Emami and Dadashpour, 2015</xref>; <xref ref-type="bibr" rid="B65">Upadhyay, 2021</xref>). The numerous advancements and uses of coumarin-1,2,3-triazole hybrid compounds as potential bioactive leads have already been outlined in a number of reviews (<xref ref-type="bibr" rid="B18">Emami and Dadashpour, 2015</xref>; <xref ref-type="bibr" rid="B19">Fan et al., 2018</xref>; <xref ref-type="bibr" rid="B2">Al-Warhi et al., 2020</xref>; <xref ref-type="bibr" rid="B59">Song et al., 2020</xref>; <xref ref-type="bibr" rid="B3">Alam, 2022</xref>). Significant work has been done in recent years on the design, synthesis, and assessment of numerous hybrid compounds based on coumarin-1,2,3-triazoles as anticancer agents, the compilation of which may generate important findings for the development of novel anticancer drugs. An effort has been made to outline recent advancements in the development of hybrid compounds based on coumarin-1,2,3-triazoles as anticancer agents in this stand-alone review. The original research articles were searched in the Pubmed and Google Scholar databases under the keywords &#x201c;Coumarin-1,2,3-triazole hybrid molecules as anticancer agents&#x201d;, &#x201c;Coumarin-1,2,3-triazole &#x2b; anticancer&#x2019;, Coumarin-1,2,3-triazole &#x2b; antiproliferative&#x201d; etc. The considered range of publication year was January 2012-July 2022, under which more than twenty-five original research articles on various coumarin-1,2,3-triazole hybrids with anticancer activity on a total of thirty-two cancer cell lines were finally taken in consideration. The current review will enable researchers to develop novel anticancer coumarin-1,2,3-triazole hybrids that are far more precise and have greater activity.</p>
<sec id="s1-1">
<title>Coumarin and 1,2,3-triazole: The scaffolds with broad range biological activities</title>
<p>Coumarin (2H-1-Benzopyran-2-one) are phenolic compounds which is association of <italic>&#x3b2;</italic>-pyrone rings with benzene, widely distributed in plants bacteria and fungi (<xref ref-type="bibr" rid="B1">Abyshev et al., 2006</xref>; <xref ref-type="bibr" rid="B25">Katsori and Hadjipavlou-Litina, 2014</xref>). Fundamentally, the benzopyrones have been split into two groups: benzo-&#x3b1;-pyrones, which are the primary class of coumarin, and benzo-<italic>&#x3b3;</italic>-pyrones, which mostly contain flavonoids (<xref ref-type="bibr" rid="B32">Lacy and O&#x2019;Kennedy, 2004</xref>; <xref ref-type="bibr" rid="B31">Lacy, 2005</xref>). In plants, most of the benzopyrones are reported to exist in the form of glycosides making them highly polar (<xref ref-type="bibr" rid="B36">Matos et al., 2015</xref>). Coumarins are a varied class of naturally occurring pharmacophores with a wide range of bioactivities <italic>viz.</italic> anti-inflammatory, antioxidant, antinociceptive, hepatoprotective, antithrombotic, antiviral, antimicrobial, antituberculosis, anticancer, antidepressant, antihyperlipidemic, anti-Alzheimer, anticholinesterase, and antiviral activities (<xref ref-type="bibr" rid="B67">Upadhyay et al., 2012</xref>; <xref ref-type="bibr" rid="B25">Katsori and Hadjipavlou-Litina, 2014</xref>; <xref ref-type="bibr" rid="B28">Kraljevi&#x107; et al., 2016</xref>; <xref ref-type="bibr" rid="B56">Singh et al., 2019</xref>; <xref ref-type="bibr" rid="B71">Wang et al., 2020</xref>). There are numerous clinically effective compounds, both natural and synthetic, containing coumarin scaffolds (<xref ref-type="bibr" rid="B18">Emami and Dadashpour, 2015</xref>; <xref ref-type="bibr" rid="B68">Upadhyay, 2019</xref>) (<xref ref-type="fig" rid="F1">Figure 1</xref>). Coumarins are reported to possess anticancer activity with minimal side effects (<xref ref-type="bibr" rid="B38">Musa et al., 2008</xref>; <xref ref-type="bibr" rid="B60">Stefanachi et al., 2018</xref>; <xref ref-type="bibr" rid="B47">Rawat and Vijaya Bhaskar Reddy, 2022</xref>). They have the ability to regulate a wide variety of cellular pathways involved in cancer, including those involved in kinase inhibition, cell cycle arrest, angiogenesis, heat shock protein (HSP90) inhibition, telomerase inhibition, antimitotic activity, carbonic anhydrase inhibition, monocarboxylate transporters inhibition, aromatase inhibition, and sulfatase inhibition, each of which can be explored for specific anticancer activity (<xref ref-type="bibr" rid="B64">Thakur et al., 2015</xref>; <xref ref-type="bibr" rid="B21">Goud et al., 2020</xref>; <xref ref-type="bibr" rid="B74">Wu et al., 2020</xref>).</p>
<fig id="F1" position="float">
<label>FIGURE 1</label>
<caption>
<p>Some notable drugs with coumarin moiety.</p>
</caption>
<graphic xlink:href="fddsv-02-1072448-g001.tif"/>
</fig>
<p>Nitrogen-based heterocyclic secondary metabolites are widely reported from plants, fungi, algae etc. Numerous heterocyclic compounds with nitrogen have been found to have a variety of pharmacological effects, including anti-cancer, anti-HIV, anti-malarial, anti-tubercular, anti-microbial, and antidiabetic properties (<xref ref-type="bibr" rid="B24">Joule, 2016</xref>; <xref ref-type="bibr" rid="B52">Shang et al., 2018</xref>; <xref ref-type="bibr" rid="B20">Gopalakrishnan et al., 2021</xref>). Because nitrogen can interact in a variety of ways with biological targets, both naturally occurring and synthesized nitrogen-based heterocyclic molecules have drawn the interest of medicinal chemists (<xref ref-type="bibr" rid="B26">Kerru et al., 2020</xref>; <xref ref-type="bibr" rid="B65">Upadhyay, 2021</xref>). The importance of nitrogen-based heterocycles can be judged not only in the form of approximately countless published research articles but also in the form of clinical molecules in the therapy of various diseases and debilities (<xref ref-type="bibr" rid="B26">Kerru et al., 2020</xref>; <xref ref-type="bibr" rid="B20">Gopalakrishnan et al., 2021</xref>). A lot of representative nitrogen heterocycles <italic>viz.</italic> Ciprofloxacin, Tazobactum, Cefatrizine (antibiotic); Oxiconazole, Clotrimazole (Antifungal); Celecoxib (Anti-inflammatory), Rimonabant (Anti-obesity), Difenamizole (Anti-analgesic), Fezolamine (Antidepressant), Bedaquiline (Anti-TB), Pitavastatin (Cholesterol-lowering agent), Gefitinib (Growth factor receptor (EGFR) tyrosine kinase inhibitor), Ezetimibe (Cholesterol absorption inhibitor), Clavulanic acid (&#x3b2;-Lactamase inhibitor) are in regular clinical practice (<xref ref-type="bibr" rid="B26">Kerru et al., 2020</xref>). Some of the noticeable nitrogen heterocycle-based molecules as anticancer drugs are Erlotinib, Lapatinib, Ibrutinib, Capecitabine, Folinic acid, Monastrol, Dacarbazine, and Carboxyamidotriazole (<xref ref-type="bibr" rid="B45">Perabo et al., 2004</xref>; <xref ref-type="bibr" rid="B48">Romero et al., 2004</xref>; <xref ref-type="bibr" rid="B14">Dorababu, 2020</xref>; <xref ref-type="bibr" rid="B26">Kerru et al., 2020</xref>; <xref ref-type="bibr" rid="B65">Upadhyay, 2021</xref>). Amongst all the nitrogen-based molecules, the 1,2,3-triazole is a privileged moiety in biologically active leads putting its importance in the field of medicinal chemistry (<xref ref-type="bibr" rid="B65">Upadhyay, 2021</xref>). <xref ref-type="fig" rid="F2">Figure 2</xref> shows a few examples of typical pharmaceuticals with a 1,2,3-triazole moiety. Due to the triazole unit&#x2019;s strong dipole properties driven by the presence of three nitrogen atoms, a wide range of biological targets can be bound to it with a high affinity (<xref ref-type="bibr" rid="B33">Liang et al., 2021</xref>). The 1,2,3-triazoles have been claimed to have a variety of pharmacological effects as well as anticancer effects through a variety of mechanisms of action (<xref ref-type="bibr" rid="B33">Liang et al., 2021</xref>; <xref ref-type="bibr" rid="B3">Alam, 2022</xref>). Their anticancer property is due to inhibition of the enzymes that contribute to the development of this deadly disease, such as the carbonic anhydrases (CAs), thymidylate synthase (TS), aromatase, tryptophan-2,3-dioxygenase (TDO), vascular endothelial growth factor receptor (VEGFR), and epidermal growth factor receptor (EGFR) (<xref ref-type="bibr" rid="B45">Perabo et al., 2004</xref>; <xref ref-type="bibr" rid="B33">Liang et al., 2021</xref>).</p>
<fig id="F2" position="float">
<label>FIGURE 2</label>
<caption>
<p>Some notable drugs with triazole moiety.</p>
</caption>
<graphic xlink:href="fddsv-02-1072448-g002.tif"/>
</fig>
</sec>
<sec id="s1-2">
<title>Coumarin-1,2,3-triazole hybrid molecules as anticancer agents</title>
<p>Combining biologically relevant moieties with different modes of action to create hybrid therapeutic molecules is a brilliant strategy that may lead to the development of drugs with improved pharmacological properties for the treatment of complicated disorders, such as cancer (<xref ref-type="bibr" rid="B53">Shaveta et al., 2016</xref>; <xref ref-type="bibr" rid="B37">Mohamed and Abuo-Rahma, 2020</xref>). Hybrid drugs can affect several targets involved in the growth of cancer cells at once, and as a result, they have received a lot of attention in recent years (<xref ref-type="bibr" rid="B75">Xu et al., 2019a</xref>; <xref ref-type="bibr" rid="B6">Bozorov et al., 2019</xref>; <xref ref-type="bibr" rid="B33">Liang et al., 2021</xref>; <xref ref-type="bibr" rid="B3">Alam, 2022</xref>). Recently there is a burst in the synthesis and assessment of coumarin-1,2,3-triazole based anticancer hybrid molecules. The major anticancer hybrid molecules covered in this review are simple coumarin-1,2,3-triazoles, chalcone-coumarin-1,2,3-triazoles, 1,2,3-triazole tethered C5-curcuminoid coumarin hybrids, 1,2,3-triazole tethered isatin-coumarin hybrids, morpholines linked coumarin-1,2,3-triazole hybrids, tetraethylene glycol-tethered isatin&#x2013;1,2,3-triazole&#x2013;coumarin hybrids, coumarin-1,2,3-triazole-podophyllotoxin hybrids, &#x3b1;, <italic>&#x3b2;</italic>-unsaturated carbonyl linked coumarin-triazole hybrids, and 1,2,3-triazole-coumarin-glycosyl hybrids.</p>
<p>Duan <italic>et al.</italic> Synthesised a series of coumarin-1,2,3-triazole-dithiocarbamate hybrids, which displayed good anticancer activity against human gastric carcinoma (MGC-803) and human breast cancer (MCF-7) cell lines, but all the derivatives were inactive against esophageal cancer (EC-109) cell line (IC<sub>50</sub> &#x3e; 128&#xa0;&#xb5;M). The substitution of coumarin moiety with 1,2,3-triazole-dithiocarbamate residue at position 4 (derivative <bold>1</bold>) led to potent anticancer activity against the MGC-803 (IC<sub>50</sub> 4.96&#xa0;&#xb5;M), MCF-7 (IC<sub>50</sub> 10.44&#xa0;&#xb5;M) and prostate cancer (PC-3) cell line (IC<sub>50</sub> 36.84&#xa0;&#xb5;M), while the substitution with same residue at position 7 led to molecules with decreased anticancer activity (derivatives <bold>2a-b</bold>) in range of 67.05 &#xb5;M&#x2013;90.38&#xa0;&#xb5;M (<xref ref-type="bibr" rid="B15">Duan et al., 2013</xref>). A series of chalcone-coumarin derivatives linked by the 1,2,3-triazole ring (<bold>3</bold>&#x2013;<bold>9</bold>) were prepared and assessed for cytotoxic activity against human liver bile duct (HuCCA-1), human hepatocellular (HepG2), adenocarcinomic human alveolar basal epithelial (A549) and human malignant T-lymphoblastic (MOLT-3) cancer cell lines by Pingaew <italic>et al.</italic> Most of the synthesized hybrids, except for hybrid <bold>5</bold>, exhibited cytotoxicity against MOLT-3 cell line without affecting normal cells. SAR study systematically disclosed the effect of substitution pattern in both rings (A &#x26; B) of chalcone moiety. The hybrids with, 3/4 triazole at ring A and 2,3-di-OMe at ring B show potent HepG2 inhibitory effect as evident from IC<sub>50</sub> values 15.70, 8.18 and 4.26&#xa0;&#xb5;M for compounds <bold>4</bold>, <bold>5</bold> and <bold>7</bold> respectively. Meantime, hybrids with 3/4 triazole at ring A and tri-OMe substitution at ring B (<bold>8</bold>, <bold>9</bold>) were shown to lose the cytotoxic effect against HuCCA-1, HepG2, A549 except for <bold>8</bold>, which showed IC<sub>50</sub> 6.13&#xa0;&#xb5;M against HuCCA-1 (<xref ref-type="bibr" rid="B46">Pingaew et al., 2014</xref>). A series of 4-(1,2,3-triazol-1-yl)-coumarin derivatives were synthesized and evaluated for their anticancer activity against MCF-7, A549, and colorectal (SW480) human cancer cell lines. Most of the molecules exhibited significant antiproliferative activities. Compounds <bold>10a-d</bold> exhibited IC<sub>50</sub> values of 9.45, &#x3e;50, 36.83 and 1.72 respectively against MCF-7 cell line, from which SAR may be established that&#x2013;CH<sub>2</sub>O&#x2013;bridge at C-4 position of 1,2,3-triazole nucleus on phenyl moiety is the best linker for cytotoxic activity (<xref ref-type="bibr" rid="B80">Zhang et al., 2014</xref>). Further, a close observation on 2/4 substituted phenoxy derivatives <bold>11&#x2013;23</bold> (IC<sub>50</sub> values 34.14, 28.91, 24.82, 12.67, 2.04, 1.92, 11.41, 7.00, 3.13, 5.84, 8.56, 4.62, and 5.89&#xa0;&#x3bc;M respectively against MCF-7 cell line) reveals that the anticancer action is enhanced by the presence of a hydrogen bond acceptor, such as a fluorine atom at the C-4 position of the phenoxy moiety and a methoxy group at the C-7 position of coumarin (<xref ref-type="bibr" rid="B80">Zhang et al., 2014</xref>). Amongst all, the 4-(4-((4-fluorophenoxy) methyl)-1,2,3-triazol-1-yl)-7-methoxycoumarin (<bold>23)</bold> was found potentially active against all the tested cancer cell lines with IC<sub>50</sub> values of 5.89, 1.99 and 0.52&#xa0;&#x3bc;M against MCF-7, SW480 and A549 respectively. In further studies, the compound <bold>23</bold> was found to possess ability to arrest the cell-cycle at G2/M phase (<xref ref-type="bibr" rid="B80">Zhang et al., 2014</xref>). A series of 2-(4-R-triazolyl)-substituted 3-oxo-2,3-dihydrofurocoumarins was synthesized and evaluated against acute lymphoblastic leukaemia (CEM-13), membrane-type 4 (MT-4), myeloid leukaemia (U-937) human cancer cell lines using MTT assays. Most of the synthesized hybrids were active against the tested cell lines. It was observed that the selective cytotoxic activity to cancer cell lines interestingly increased in hybrid <bold>24</bold> bearing the 4-hydroxy-3-methoxybenzamidomethyl moiety on the triazole ring which showed 50% cytotoxic dose (CTD50) values 9.00, 10.00 and 8.00&#xa0;&#xb5;M respectively against CEM-13, MT-4, U-937 cancer cell lines. The hybrid <bold>24</bold> showed higher binding affinity (-9.2&#xa0;kcal/mol) to active sites of the anticancer target PDE4B (Phosphodiesterase-4B), comparable to Rolipram (-8.3&#xa0;kcal/mol), the standard drug (<xref ref-type="bibr" rid="B34">Lipeeva et al., 2015</xref>). The structure of coumarin-1,2,3-triazole hybrids <bold>1</bold>&#x2013;<bold>24</bold> have been depicted in <xref ref-type="fig" rid="F3">Figure 3</xref>.</p>
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<label>FIGURE 3</label>
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<p>Structure of coumarin-1,2,3-triazole-dithiocarbamate hybrids (<bold>1</bold>,<bold>2</bold>), 1,2,3-triazole linked chalcone-coumarin hybrids (<bold>3</bold>&#x2013;<bold>9</bold>), 4-(1,2,3-triazol-1-yl)-coumarin hybrids (<bold>10</bold>&#x2013;<bold>23</bold>), and 2-(4-R-triazolyl)-substituted 3-oxo-2,3-dihydrofurocoumarin hybrid (<bold>24</bold>).</p>
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<p>A series of 1,2,3-triazole tethered coumarin 4-substituted alkyl, phenyl, alkylphenyl, dithiocarbamate, benzenesulfonamide, and benzofused heterocycle subunit were designed and synthesized by Kraljevic <italic>et al.</italic> for the evaluation of <italic>in vitro</italic> antiproliferative activity against human cancer cell lines A549, HepG2, CFPAC-1 (ductal pancreatic), HeLa (cervical cancer) and SW620 (colorectal cancer). Most of the compounds showed inhibitory effects against A549 and HeLa cell lines (IC<sub>50</sub> &#x2264; 30&#xa0;&#x3bc;M). It was noticed that there is a strong correlation between lipophilicity and antiproliferative activities, suggesting that lipophilic 1,2,3-triazole-coumarin hybrids with the subunits phenylethyl (<bold>25</bold>), 3,5-difluorophenyl (<bold>26</bold>), 5-iodoindole (<bold>27</bold>) and benzimidazole (<bold>28</bold> and <bold>29</bold>) (<xref ref-type="fig" rid="F4">Figure 4</xref>) may very well have cytostatic potential (<xref ref-type="bibr" rid="B28">Kraljevi&#x107; et al., 2016</xref>). The 7-methylcoumarin&#x2013;1,2,3-triazole&#x2013;2-methylbenzimidazole hybrid <bold>28</bold> showed maximum cytotoxicity against HepG2 cells with IC<sub>50</sub> value of 0.9&#xa0;&#x3bc;M with high selectivity (SI &#x3d; 50). The strong antiproliferative activity of <bold>28</bold> may be related to its suppression of 5-lipoxygenase (5-LO) activity and disruption of sphingolipid signalling by interfering with intracellular acid ceramidase (ASAH) activity (<xref ref-type="bibr" rid="B28">Kraljevi&#x107; et al., 2016</xref>). Singh <italic>et al.</italic> synthesized 1,2,3-triazole tethered C5-curcuminoid coumarin bifunctional hybrids and evaluated them against THP-1 (acute monocytic leukemia), COLO-205 (colon), HCT-116 (colon) and PC-3 human cancer cell lines. The hybrid compounds <bold>30a-b</bold> and <bold>31</bold> (<xref ref-type="fig" rid="F4">Figure 4</xref>) exhibited cytotoxicity against THP-1, COLO-205, and HCT-116 with IC<sub>50</sub> values ranging from 0.82 to 4.68, 2.34&#x2013;6.78, and 4.48&#x2013;9.95&#xa0;&#x3bc;M respectively. The hybrid compounds, however, had no effect on the prostate cancer cell line (PC-3). It has been observed that the anticancer effect depends on the presence of a two-carbon spacer between the coumarin and triazole molecule (<xref ref-type="bibr" rid="B55">Singh et al., 2016</xref>). In another strategy to design novel anticancer hybrid molecules, the authors synthesized a series of 1,2,3-triazole tethered isatin-coumarin hybrids by applying click chemistry approach and evaluated their cytotoxic potential. The compounds <bold>32&#x2013;44</bold> (<xref ref-type="fig" rid="F4">Figure 4</xref>) displayed significant cytotoxicity against THP-1 (IC<sub>50</sub> values 0.73, 1.99, 5.47, 6.43, 7.01, 8.57, 5.03, 5.76, 6.99, 7.14, 5.12, 7.10, 7.56&#xa0;&#xb5;M respectively), COLO-205 (IC<sub>50</sub> values 3.45, 6.67, 8.87, 10.53, 12.01, 12.97, 5.71, 8.88, 10.66, 12.99, 7.67, 9.11, 13.14 respectively), and HCT-116 (IC<sub>50</sub> values 3.04, 5.41, 5.77, 8.09, 8.99, 9.54, 5.18, 7.26, 9.66, 11.46, 8.05, 10.44, 12.76 respectively) human cancer cell lines. The most potent compound <bold>32</bold> displayed IC<sub>50</sub> 0.73, 3.45 and 3.04&#xa0;&#xb5;M against THP-1, COLO-205, and HCT-116 respectively, and also endowed with most prominent tubulin polymerization inhibition potential with an IC<sub>50</sub> value of 1.06&#xa0;&#x3bc;M. Compound <bold>33</bold> having fluoro substitution on isatin, exhibited IC<sub>50</sub> 1.99, 6.67, and 5.41&#xa0;&#xb5;M against THP-1, COLO-205, and HCT-116 respectively. SAR indicates that both increase in length of carbon-bridge connecting isatin moiety with triazole ring, and substitution on isatin retards the cytotoxic potential (<xref ref-type="bibr" rid="B57">Singh et al., 2017</xref>). Goud <italic>et. al</italic>. synthesized a series of morpholine linked coumarin-1,2,3-triazole hybrids and evaluated against five human cancer cell lines, namely, bone (MG-63), lung (A549), breast (MDA-MB-231), colon (HCT-15) and liver (HepG2), using MTT assay. Among the synthesized, compounds <bold>45&#x2013;53</bold> (<xref ref-type="fig" rid="F4">Figure 4</xref>) showed far better activity than the standard drug cisplatin against MG-63 and A549 cancer cell lines except <bold>47</bold> (IC<sub>50</sub> 19.47&#xa0;&#xb5;M) against MG-63. The compounds <bold>46</bold> and <bold>50</bold> showed better cytotoxic activity than cisplatin against MDA-MB-231, HCT-15, and HepG2 cancer cell lines than cisplatin. Among all, compound <bold>50</bold> was found most potent, showing IC<sub>50</sub> values 0.80, 2.97, 4.05, 3.93, and 7.19&#xa0;&#xb5;M against MG-63, A549, HCT-15, MDA-MB-231, and HepG2 respectively. Meantime, cisplatin showed IC<sub>50</sub> 17.42, 24.15, 19.45, 16.97, and 25.73&#xa0;&#xb5;M against MG-63, A549, HCT-15, MDA-MB-231, and HepG2 respectively. It was concluded that dimethylmorpholine derivatives with an electron-withdrawing group viz. <bold>50</bold> and <bold>51</bold> are more cytotoxic than simple morpholine derivatives like <bold>45</bold>, <bold>46,</bold> and <bold>48</bold>. The compound <bold>50</bold> induced sub-G1 phase arrest, increased apoptosis, and promoted the production of reactive oxygen species justifying the potential cytotoxic activity (<xref ref-type="bibr" rid="B22">Goud et al., 2019</xref>). <italic>In vitro</italic> anticancer activities of several isatin-1,2,3 triazole-tethered coumarin hybrids were investigated against HepG2, Hela, A549, DU145 (prostate cancer), SKOV3 (ovarian carcinoma), MCF-7, and drug-resistant MCF-7/DOX (doxorubicin-resistant MCF-7) human cancer cell lines. The hybrids <bold>54&#x2013;55</bold> (<xref ref-type="fig" rid="F4">Figure 4</xref>) showed weak to moderate (IC<sub>50</sub> 17.96 to <italic>&#x3e;</italic>50&#xa0;&#x3bc;M) <italic>in vitro</italic> anticancer activities. SAR indicated that hydrogen-bond donor&#x2013;NOH group at C-3, and electron-donating methyl group at C-5 positions of isatin motif could significantly enhance the anticancer activity as evident in case of hybrid <bold>55</bold> (<xref ref-type="bibr" rid="B13">Diao et al., 2019</xref>).</p>
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<label>FIGURE 4</label>
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<p>Structure of 1,2,3-triazole tethered coumarin 4-substituted hybrids (<bold>25</bold>&#x2013;<bold>29</bold>), 1,2,3-triazole tethered C5-curcuminoid coumarin hybrids (<bold>30</bold>&#x2013;<bold>31</bold>), isatin-1,2,3 triazole-4-coumarin hybrids (<bold>32</bold>&#x2013;<bold>44</bold>), morpholines linked coumarin-1,2,3-triazole hybrids (<bold>45</bold>&#x2013;<bold>53</bold>), isatin-1,2,3 triazole-7-coumarin hybrids (<bold>54</bold>&#x2013;<bold>55</bold>).</p>
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<p>Xu et al. synthesized a series of tetraethylene glycol-tethered isatin&#x2013;1,2,3-triazole&#x2013;coumarin hybrids and assessed for <italic>in vitro</italic> cytotoxic activities against seven human cancer cell lines, namely HepG2, Hela, A549, DU145 (prostate), SKOV3 (ovarian adenocarcinoma), MCF-7 and MCF-7/DOX. Weak to moderate anticancer activity were displayed by the hybrid compounds. The hybrids <bold>56&#x2013;58</bold> (<xref ref-type="fig" rid="F5">Figure 5</xref>) were found active against all the tested cell lines in a range of IC<sub>50</sub> values 20.09&#x2013;49.24&#xa0;&#xb5;M. The SAR indicated that the electron withdrawing group at C-5 position of isatin motif enhances the anticancer activity (<xref ref-type="bibr" rid="B76">Xu et al., 2019b</xref>). Hao <italic>et al.</italic> synthesized a series of coumarin-1,2,3-triazole-podophyllotoxin hybrid molecules using the click reaction, and evaluated for their cytotoxic potential against A549, HepG2, HeLa and LoVo (colorectal) cancer cell lines using the MTT assay. Most of the hybrids exhibited equivalent or slightly weaker cytotoxic activities in all the 4 cell lines compared with that of etoposide (VP-16), the standard drug. The hybrids <bold>59</bold> exhibited IC<sub>50</sub> 8.6, 9.3, 15.2, and 8.7; while <bold>60</bold> exhibited IC<sub>50</sub> 13.3, 13.6, 19.8, and 7.3&#xa0;&#x3bc;M against A549, HepG2, HeLa, and LoVo cells, respectively. Among all, hybrid <bold>61</bold> exhibited the most potent cytotoxicity, with IC<sub>50</sub> values of 17.5, 9.9, 9.7, and 4.9&#xa0;&#x3bc;M against A549, HepG2, HeLa, and LoVo cells, respectively, which was far better than the standard VP-16 (IC<sub>50</sub> 25.6, 10.5, 12.2, and 14.9&#xa0;&#x3bc;M against A549, HepG2, HeLa, and LoVo cells, respectively). Additional research showed that compound <bold>61</bold> entered into the DNA of LoVo cells, selectively inhibited Topo II&#x3b2; than Topo II&#x3b1;, arrested the cell cycle in the G1 phase, and disrupted microtubule organisation. It was observed that 1,2,3-triazole-4-methylamine is a more suitable linker than 1,2,3-triazole-4-methyloxy in this series conjugates (<xref ref-type="bibr" rid="B23">Hao et al., 2019</xref>). Narsimha et al. synthesized various hybrid molecules using 3-fluoro-4-morpholinophenyl-1,2,3-triazolyl moiety. Among them the hybrid having 7-hydroxy-4-methylcoumarin at fourth position of 1,2,3-triazole (<bold>62</bold>), exhibited potent activity against both MCF-7 and HeLa cell lines with IC<sub>50</sub> values 3.12 and 2.77 &#x3bc;M, respectively. The cytotoxic activity of <bold>62</bold> was comparable to the standard drug doxorubicin (IC<sub>50</sub> values 2.63&#xa0;&#x3bc;M in MCF-7 and 1.23&#xa0;&#x3bc;M in HeLa cells). The cytotoxic activity of the hybrid having 4-hydroxycoumarin at fourth position of 1,2,3-triazole (<bold>63</bold>) also exhibited significant cytotoxicity against the two cancer cell lines MCF-7 and HeLa with IC<sub>50</sub> values 5.19 and 12.42 &#x3bc;M, respectively. Both the compounds were almost inactive (IC<sub>50</sub> values 58.11 and 66.38&#xa0;&#x3bc;M respectively) against HEK-293 cancer cell lines (<xref ref-type="bibr" rid="B39">Narsimha et al., 2020</xref>). Coumarin-tagged <italic>&#x3b2;</italic>-lactam triazole hybrids (<bold>64a-b</bold>) showed moderate cytotoxic activity against MCF-7 cancer cell lines with IC<sub>50</sub> values of 53.55 and 58.62&#xa0;&#x3bc;M, respectively. Both the derivatives showed high binding affinity (binding energies &#x2212;11.3 and &#x2212;10.9&#xa0;kcal/mol respectively) with the target estrogen receptor-&#x3b1; (ER-&#x3b1;) (<xref ref-type="bibr" rid="B12">Dhawan et al., 2020</xref>). A range of bifunctional molecular hybrids based on uracil and coumarin, roped with 1,2,3-triazole moiety were synthesized and assessed against six human cancer cell lines, namely Colo-205, MCF-7, A549, PA-1 (ovarian), PC-3 (prostate) and Hela cells by Sulforhodamine B assay. The synthesized molecules (<bold>65&#x2013;68</bold>) were potentially active against MCF-7 cancer cell proliferation (<xref ref-type="bibr" rid="B49">Sanduja et al., 2020</xref>). The compounds <bold>65a</bold>-<bold>f</bold>, <bold>66a</bold>-<bold>e</bold>, <bold>67a</bold>-<bold>c</bold> and <bold>68a</bold>-<bold>b</bold> showed 50% cell growth inhibitory concentration (GI<sub>50</sub>) 1.55&#x2013;6.88&#xa0;&#xb5;M, even better than the standard drug 5-Fluorouracil (GI<sub>50</sub> 5.28&#xa0;&#xb5;M). The compounds <bold>67d</bold>, <bold>67e</bold>, <bold>68c</bold>, <bold>68d</bold>, and <bold>68e</bold> (<xref ref-type="fig" rid="F5">Figure 5</xref>) also exhibited potential activity against MCF-7 cancer cell line with GI<sub>50</sub> values 7.75, 9.77, 7.29, 9.33, and 12.24&#xa0;&#xb5;M respectively. Amongst all, <bold>65a</bold> (with a fluorine atom as R with two carbon chain length between triazole and coumarin moieties) was found to be a most potent hybrid (GI<sub>50</sub> &#x3d; 1.55&#xa0;&#xb5;M). The hybrid <bold>65a</bold> strongly inhibited the proliferation of MCF-7 cells by deferring the G2/M phase in cell cycle analysis studies. Further, in attempt to gain insight on interactions between <bold>65a</bold> and the tubulin protein, docking studies were performed. The results indicated that <bold>65a</bold> fit well at the interface of &#x3b1;2 and &#x3b2;1 subunits of tubulin (vinblastine binding site) and is stabilized by hydrogen bonding as well as van der Waal&#x2019;s interactions suggesting it a potential lead for the discovery and development of novel treatments of breast cancer (<xref ref-type="bibr" rid="B49">Sanduja et al., 2020</xref>). Noticeable that, hybrids with substituted uracil (electron withdrawing or electron donating) were more active than the hybrids with unsubstituted uracil. With the length of the chain increasing, the hybrid molecules&#x2019; activity reduced. Fluorine-substituted hybrids had the strong activity, and halogen substitution at C5 of uracil was found necessary for the activity (<xref ref-type="bibr" rid="B49">Sanduja et al., 2020</xref>). A series of &#x3b1;, <italic>&#x3b2;</italic>-unsaturated carbonyl linked coumarin-1,2,3-triazole hybrids, <bold>69&#x2013;71</bold> were synthesized by microwave irradiation conditions and were screened <italic>in vitro</italic> for their anticancer activity. The hybrid <bold>70</bold> was found most potent, exhibiting IC<sub>50</sub> 10.538 and 9.845&#xa0;&#xb5;M respectively against PC-3 and DU-145 cell lines. The hybrids <bold>69</bold> and <bold>71</bold> were equally effective against PC-3 cell lines (IC<sub>50</sub>16.254 and 16.652&#xa0;&#xb5;M respectively) (<xref ref-type="bibr" rid="B70">Vagish et al., 2021</xref>). <xref ref-type="fig" rid="F5">Figure 5</xref> shows the structure of the coumarin-1,2,3-triazole hybrids <bold>56</bold>&#x2013;<bold>71</bold>, and <xref ref-type="sec" rid="s6">Supplementary Tables S1, S2</xref> of the supplementary material contains <italic>in vitro</italic> cytotoxicity potential of these hybrids against various cancer cell lines.</p>
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<label>FIGURE 5</label>
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<p>Structure of tetraethylene glycol-tethered isatin&#x2013;1,2,3-triazole&#x2013;coumarin hybrids (<bold>56</bold>&#x2013;<bold>58</bold>), coumarin-1,2,3-triazole-podophyllotoxin hybrids (<bold>59</bold>&#x2013;<bold>61</bold>), 3-fluoro-4-morpholinophenyl-1,2,3-triazolyl coumarin hybrids (<bold>62</bold>&#x2013;<bold>63</bold>), Coumarin-tagged <italic>&#x3b2;</italic>-lactam triazole hybrid (<bold>64</bold>), 1,2,3-triazole roped uracil-coumarin bifunctional hybrids (<bold>65</bold>&#x2013;<bold>68</bold>), &#x3b1;, <italic>&#x3b2;</italic>-unsaturated carbonyl linked coumarin-1,2,3-triazole hybrids (<bold>69</bold>&#x2013;<bold>71</bold>).</p>
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<p>The Zinc-binding enzymes called human carbonic anhydrases (hCAs) catalyse the reversible hydration of carbon dioxide to bicarbonate (<xref ref-type="bibr" rid="B29">Kumar et al., 2021</xref>). Various hCA isoforms have been isolated, and are reported to play crucial physiological roles. The over expressing of hCA isoforms, I, II, IX, and XII is found in maintaining neutral intracellular pH necessary for tumour cells to tolerate hypoxic conditions, hence, hCA inhibitors may be a good anticancer agent (<xref ref-type="bibr" rid="B44">Pastorek et al., 2008</xref>; <xref ref-type="bibr" rid="B58">Singh et al., 2018</xref>; <xref ref-type="bibr" rid="B62">Supuran, 2018</xref>; <xref ref-type="bibr" rid="B2">Al-Warhi et al., 2020</xref>). Many hCA IX/XII inhibitors belonging to the coumarin and sulfocoumarin classes completed a successful Phase I clinical trial for the treatment of advanced, metastatic solid tumors (<xref ref-type="bibr" rid="B44">Pastorek et al., 2008</xref>). In an attempt to search novel hCA inhibitors, a series of bis-coumarin derivatives linked with 1,2,3-triazole ring and alkyl chain (<bold>72a-d</bold>) (<xref ref-type="fig" rid="F6">Figure 6</xref>) were synthesized. The derivatives showed selective inhibitory activity against hCA isoforms IX and XII. Among them <bold>72c</bold> showed highest hCA IX inhibition (Ki &#x3d; 144.6&#xa0;nM) while <bold>72b</bold> showed the highest hCA XII inhibition (Ki &#x3d; 71.5&#xa0;nM). The derivatives showed potent <italic>in vitro</italic> cytotoxicity (IC<sub>50</sub> 0.383&#x2013;13.552&#xa0;&#xb5;M) against renal adenocarcinoma (769P), HepG2 and MDA-MB-231 cell lines. The derivative <bold>72a</bold> showed the strongest cytotoxic effect against HepG2 with an IC<sub>50</sub> value of 0.383 &#x3bc;M, which is almost 2-fold more than that of standard drug Doxorubicin (<xref ref-type="bibr" rid="B30">Kurt et al., 2019</xref>). The results were fully supported by <italic>in silico</italic> binding energies with hCA isoform in docking studies (<xref ref-type="bibr" rid="B30">Kurt et al., 2019</xref>). Another series of hybrids comprising coumarin-1,2,3-triazole-benzaldehyde and coumarin-1,2,3-triazole-sulphonamide were synthesized and evaluated for their hCA I, II, IX, and XII inhibition potential. All the coumarin-1,2,3-triazole-benzaldehyde hybrids (<bold>73&#x2013;76</bold>) (<xref ref-type="fig" rid="F6">Figure 6</xref>) were not inhibiting hCA I, II and XII (Ki &#x3e; 10,000&#xa0;nM) except <bold>73</bold> which showed strong inhibition to XII (Ki &#x3d; 60.9&#xa0;nM). The hybrid <bold>73</bold> was also a potential inhibitor of IX (Ki &#x3d; 127.5&#xa0;nM) and showed strong cytotoxic effect against HT-29 (human colorectal adenocarcinoma) cancer cell line exhibiting IC<sub>50</sub> value of 18.89&#xa0;&#xb5;M. The hybrids <bold>74</bold>, <bold>75</bold>, and <bold>76</bold> showed IC<sub>50</sub> values 13.3, 9.03, and 7.47&#xa0;&#xb5;M respectively against HT-29 cancer cell lines (<xref ref-type="bibr" rid="B79">Zengin Kurt et al., 2019</xref>). The coumarin-1,2,3-triazole-sulphonamide hybrids (<bold>77&#x2013;80</bold>) (<xref ref-type="fig" rid="F6">Figure 6</xref>) were found to be potential inhibitors of hCA II, IX, and XII at nanomolar levels of Ki. Further, hybrids, <bold>77</bold>, <bold>78</bold>, <bold>79</bold> and <bold>80</bold> showed IC<sub>50</sub> values 14.29, 23.34, 17.7, and 17.01&#xa0;&#xb5;M respectively. Noticeable that except <bold>80</bold>, rest of the derivatives were toxic to healthy HEK293T embryonic kidney cell lines, hence hybrid <bold>80</bold> may be a promising anticancer drug candidate (<xref ref-type="bibr" rid="B79">Zengin Kurt et al., 2019</xref>). Recently, a series of 6-coumarin-linked 4-anilinomethyl-1,2,3-triazole was synthesized and evaluated for their inhibitory potential against various hCA isoforms. Compounds <bold>81a-e</bold> (<xref ref-type="fig" rid="F6">Figure 6</xref>) exhibited the best inhibitory profiles (Ki &#x3c; 100&#xa0;nM) against both against CA IX, and XII (<xref ref-type="bibr" rid="B63">Thacker et al., 2021</xref>). New analogues of triazole-coumarin-glycosyl hybrids were synthesized and screened for their cytotoxic activities against Paca-2 (pancreatic), Mel-501 (female malignant), PC-3 (prostate) and A-375 (malignant human melanoma) cancer cell lines. The hybrids <bold>82&#x2013;84</bold> (<xref ref-type="fig" rid="F6">Figure 6</xref>) possessed potent cytotoxic activity showing 94.7&#x2013;99.6% inhibition of cell growth. The hybrid molecules <bold>82</bold>, <bold>83</bold>, and <bold>84</bold> exhibited IC<sub>50</sub> 14.6, 33.4 and 16.9&#xa0;&#xb5;M respectively against Paca-2, and 16.7, 65.1 and 4.1&#xa0;&#xb5;M respectively against Mel-501 cancer cell lines. The <italic>in vitro</italic> cytotoxicity of <bold>82</bold> and <bold>84</bold> against Paca-2 were far better than the standard drug Doxorubicin (IC<sub>50</sub> 19.4&#xa0;&#xb5;M) (<xref ref-type="bibr" rid="B17">El-Sayed et al., 2022</xref>). However, the results were much more promising for coumarin-tetrazole derivative synthesized by the authors which displayed potent cytotoxic activity, broad superior inhibitory activity and high <italic>in silico</italic> binding affinity against anticancer enzymes EGFR (epidermal growth factor receptor), VEGFR-2 (Vascular endothelial growth factor receptor 2) and Cyclin dependent kinase 2 (CDK-2)/cyclin A2 Kinases (<xref ref-type="bibr" rid="B17">El-Sayed et al., 2022</xref>).</p>
<fig id="F6" position="float">
<label>FIGURE 6</label>
<caption>
<p>Structure of 1,2,3-triazole linked bis-coumarin hybrid (<bold>72</bold>), coumarin-1,2,3-triazole-benzaldehyde hybrids (<bold>73</bold>&#x2013;<bold>76</bold>), coumarin-1,2,3-triazole-sulphonamide hybrids (<bold>77</bold>&#x2013;<bold>80</bold>), 6-coumarin-linked 4-anilinomethyl-1,2,3-triazole hybrid (<bold>81</bold>), 1,2,3-triazole-coumarin-glycosyl hybrids (<bold>82</bold>&#x2013;<bold>84</bold>).</p>
</caption>
<graphic xlink:href="fddsv-02-1072448-g006.tif"/>
</fig>
<p>Overall SAR could be established for most potent coumarin-1,2,3-triazole anticancer hybrids. Numerous attempts have been made for modifying different positions of coumarin nucleus resulting in a large number of compounds having a diverse mechanism of actions. Most of the efforts have been made onF modifications at positions 4 and 7 of coumarin moiety. Attachment of 1,2,3-triazole moiety at positions 4 and 7 of coumarin seems crucial for anticancer activity. A further substitution of triazole moiety by aromatic/heteroaromatic benzo-fused rings with methylene linker enhances the anticancer activity. The SAR for some of the pharmacophores with potential cytotoxic activity have been depicted in <xref ref-type="fig" rid="F7">Figure 7</xref>.</p>
<fig id="F7" position="float">
<label>FIGURE 7</label>
<caption>
<p>Structure activity relationship of some notable coumarin-1,2,3-triazole scaffolds.</p>
</caption>
<graphic xlink:href="fddsv-02-1072448-g007.tif"/>
</fig>
</sec>
</sec>
<sec sec-type="conclusion" id="s2">
<title>Conclusion</title>
<p>Millions of individuals worldwide are impacted by cancer each year, making it one of the major causes of mortality. Although both coumarin and 1,2,3-triazole moieties have proven anticancer properties, the single target drug therapies are insufficient for the treatment of cancer. The design of hybrid anticancer drugs by combining coumarin and 1,2,3-triazole moieties may produce a drug with a broader range of action acting simultaneously on multiple targets. Various coumarin-1,2,3-triazole hybrids discussed in this review have shown potential anticancer activities in terms of IC<sub>50</sub> comparable to standard clinical drugs against various cancer cell lines. The anticancer activity of potentially active hybrids has been further reported to be justified by selective inhibition of different enzymes such as EGFR, VEGFR-2 and CDK-2/cyclin A2 Kinases, Topo II&#x3b2;, and Topo II&#x3b1;, involved in the progression of cancer, arrest of the cell cycle in G1 phase, and disturbing microtubule organization. Due to much better anticancer activity than clinically used reference drugs and interesting preliminary reports on mode of action, great opportunity can be seen for some of the hybrids <italic>viz.</italic> <bold>46</bold>, <bold>50</bold>, <bold>61</bold>, <bold>65</bold>&#x2013;<bold>68</bold> reported in this review, hence further studies are recommended to explore them as a potential multi-targeted anticancer drug for clinical use. The present review represents an avenue for medicinal chemists to design and develop novel coumarin-1,2,3-triazole anticancer hybrids with better efficacy and fewer side effects.</p>
</sec>
</body>
<back>
<sec id="s3">
<title>Author contributions</title>
<p>KM and HU conceptualized, collected the information, designed and wrote the manuscript.</p>
</sec>
<ack>
<p>The authors thank Prof. Geetam Singh Tomar, Director, Rajkiya Engineering College Sonbhadra for the facilities and constructive support.</p>
</ack>
<sec sec-type="COI-statement" id="s4">
<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="s5">
<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>
<sec id="s6">
<title>Supplementary material</title>
<p>The Supplementary Material for this article can be found online at: <ext-link ext-link-type="uri" xlink:href="https://www.frontiersin.org/articles/10.3389/fddsv.2022.1072448/full#supplementary-material">https://www.frontiersin.org/articles/10.3389/fddsv.2022.1072448/full&#x23;supplementary-material</ext-link>
</p>
<supplementary-material xlink:href="DataSheet1.docx" id="SM1" mimetype="application/docx" xmlns:xlink="http://www.w3.org/1999/xlink"/>
</sec>
<ref-list>
<title>References</title>
<ref id="B1">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Abyshev</surname>
<given-names>A. Z.</given-names>
</name>
<name>
<surname>Gindin</surname>
<given-names>V. A.</given-names>
</name>
<name>
<surname>Semenov</surname>
<given-names>E. v.</given-names>
</name>
<name>
<surname>Agaev</surname>
<given-names>E. M.</given-names>
</name>
<name>
<surname>Abdulla-Zade</surname>
<given-names>A. A.</given-names>
</name>
<name>
<surname>Guseinov</surname>
<given-names>A. B.</given-names>
</name>
</person-group> (<year>2006</year>). <article-title>Structure and biological properties of 2H-1-benzopyran-2-one (coumarin) derivatives</article-title>. <source>Pharm. Chem. J.</source> <volume>40</volume>, <fpage>607</fpage>&#x2013;<lpage>610</lpage>. <pub-id pub-id-type="doi">10.1007/s11094-006-0203-7</pub-id>
</citation>
</ref>
<ref id="B2">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Al-Warhi</surname>
<given-names>T.</given-names>
</name>
<name>
<surname>Sabt</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Elkaeed</surname>
<given-names>E. B.</given-names>
</name>
<name>
<surname>Eldehna</surname>
<given-names>W. M.</given-names>
</name>
</person-group> (<year>2020</year>). <article-title>Recent advancements of coumarin-based anticancer agents: An up-to-date review</article-title>. <source>Bioorg. Chem.</source> <volume>103</volume>, <fpage>104163</fpage>. <pub-id pub-id-type="doi">10.1016/j.bioorg.2020.104163</pub-id>
</citation>
</ref>
<ref id="B3">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Alam</surname>
<given-names>M. M.</given-names>
</name>
</person-group> (<year>2022</year>). <article-title>1, 2, 3-triazole hybrids as anticancer agents: A review</article-title>. <source>Arch. Pharm.</source> <volume>355</volume>, <fpage>e2100158</fpage>. <pub-id pub-id-type="doi">10.1002/ardp.202100158</pub-id>
</citation>
</ref>
<ref id="B4">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Atanasov</surname>
<given-names>A. G.</given-names>
</name>
<name>
<surname>Zotchev</surname>
<given-names>S. B.</given-names>
</name>
<name>
<surname>Dirsch</surname>
<given-names>V. M.</given-names>
</name>
<name>
<surname>Orhan</surname>
<given-names>I. E.</given-names>
</name>
<name>
<surname>Banach</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Rollinger</surname>
<given-names>J. M.</given-names>
</name>
<etal/>
</person-group> (<year>2021</year>). <article-title>Natural products in drug discovery: Advances and opportunities</article-title>. <source>Nat. Rev. Drug Discov.</source> <volume>20</volume>, <fpage>200</fpage>&#x2013;<lpage>216</lpage>. <pub-id pub-id-type="doi">10.1038/s41573-020-00114-z</pub-id>
</citation>
</ref>
<ref id="B5">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Blagosklonny</surname>
<given-names>M. v.</given-names>
</name>
</person-group> (<year>2004</year>). <article-title>Analysis of FDA approved anticancer drugs reveals the future of cancer therapy</article-title>. <source>Cell Cycle</source> <volume>3</volume>, <fpage>1033</fpage>&#x2013;<lpage>1040</lpage>. <pub-id pub-id-type="doi">10.4161/cc.3.8.1023</pub-id>
</citation>
</ref>
<ref id="B6">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Bozorov</surname>
<given-names>K.</given-names>
</name>
<name>
<surname>Zhao</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Aisa</surname>
<given-names>H. A.</given-names>
</name>
</person-group> (<year>2019</year>). <article-title>1, 2, 3-Triazole-containing hybrids as leads in medicinal chemistry: A recent overview</article-title>. <source>Bioorg. Med. Chem.</source> <volume>27</volume>, <fpage>3511</fpage>&#x2013;<lpage>3531</lpage>. <pub-id pub-id-type="doi">10.1016/j.bmc.2019.07.005</pub-id>
</citation>
</ref>
<ref id="B7">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Bray</surname>
<given-names>F.</given-names>
</name>
<name>
<surname>Ferlay</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Soerjomataram</surname>
<given-names>I.</given-names>
</name>
<name>
<surname>Siegel</surname>
<given-names>R. L.</given-names>
</name>
<name>
<surname>Torre</surname>
<given-names>L. A.</given-names>
</name>
<name>
<surname>Jemal</surname>
<given-names>A.</given-names>
</name>
</person-group> (<year>2018</year>). <article-title>Global cancer statistics 2018: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries</article-title>. <source>Ca. Cancer J. Clin.</source> <volume>68</volume>, <fpage>394</fpage>&#x2013;<lpage>424</lpage>. <pub-id pub-id-type="doi">10.3322/caac.21492</pub-id>
</citation>
</ref>
<ref id="B8">
<citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname>Cooper</surname>
<given-names>G. M.</given-names>
</name>
<name>
<surname>Hausman</surname>
<given-names>R. E.</given-names>
</name>
</person-group> (<year>2007a</year>). <source>The cell: A molecular approach</source>. <edition>2nd Edition</edition>.</citation>
</ref>
<ref id="B9">
<citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname>Cooper</surname>
<given-names>G. M.</given-names>
</name>
<name>
<surname>Hausman</surname>
<given-names>R. E.</given-names>
</name>
</person-group> (<year>2007b</year>). <source>The development and causes of cancer. The cell: A molecular approach</source>.</citation>
</ref>
<ref id="B10">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Cragg</surname>
<given-names>G. M.</given-names>
</name>
<name>
<surname>Newman</surname>
<given-names>D. J.</given-names>
</name>
</person-group> (<year>2009</year>). <article-title>Nature: A vital source of leads for anticancer drug development</article-title>. <source>Phytochem. Rev.</source> <volume>8</volume>, <fpage>313</fpage>&#x2013;<lpage>331</lpage>. <pub-id pub-id-type="doi">10.1007/s11101-009-9123-y</pub-id>
</citation>
</ref>
<ref id="B11">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Desai</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Qazi</surname>
<given-names>G.</given-names>
</name>
<name>
<surname>Ganju</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>El-Tamer</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Singh</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Saxena</surname>
<given-names>A.</given-names>
</name>
<etal/>
</person-group> (<year>2008</year>). <article-title>Medicinal plants and cancer chemoprevention</article-title>. <source>Curr. Drug Metab.</source> <volume>9</volume>, <fpage>581</fpage>&#x2013;<lpage>591</lpage>. <pub-id pub-id-type="doi">10.2174/138920008785821657</pub-id>
</citation>
</ref>
<ref id="B12">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Dhawan</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Awolade</surname>
<given-names>P.</given-names>
</name>
<name>
<surname>Kisten</surname>
<given-names>P.</given-names>
</name>
<name>
<surname>Cele</surname>
<given-names>N.</given-names>
</name>
<name>
<surname>Pillay</surname>
<given-names>A. S.</given-names>
</name>
<name>
<surname>Saha</surname>
<given-names>S. T.</given-names>
</name>
<etal/>
</person-group> (<year>2020</year>). <article-title>Synthesis, cytotoxicity and antimicrobial evaluation of new coumarin-tagged &#x3b2;-lactam triazole hybrid</article-title>. <source>Chem. Biodivers.</source> <volume>17</volume>, <fpage>e1900462</fpage>. <pub-id pub-id-type="doi">10.1002/cbdv.201900462</pub-id>
</citation>
</ref>
<ref id="B13">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Diao</surname>
<given-names>Q. P.</given-names>
</name>
<name>
<surname>Guo</surname>
<given-names>H.</given-names>
</name>
<name>
<surname>Wang</surname>
<given-names>G. Q.</given-names>
</name>
</person-group> (<year>2019</year>). <article-title>Design, synthesis, and <italic>in vitro</italic> anticancer activities of diethylene glycol tethered isatin-1, 2, 3-triazole-coumarin hybrids</article-title>. <source>J. Heterocycl. Chem.</source> <volume>56</volume>, <fpage>1667</fpage>&#x2013;<lpage>1671</lpage>. <pub-id pub-id-type="doi">10.1002/jhet.3538</pub-id>
</citation>
</ref>
<ref id="B14">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Dorababu</surname>
<given-names>A.</given-names>
</name>
</person-group> (<year>2020</year>). <article-title>Report on recently (2017&#x2013;20) designed quinoline-based human cancer cell growth inhibitors</article-title>. <source>ChemistrySelect</source> <volume>5</volume>, <fpage>13902</fpage>&#x2013;<lpage>13915</lpage>. <pub-id pub-id-type="doi">10.1002/slct.202003888</pub-id>
</citation>
</ref>
<ref id="B15">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Duan</surname>
<given-names>Y. C.</given-names>
</name>
<name>
<surname>Ma</surname>
<given-names>Y. C.</given-names>
</name>
<name>
<surname>Zhang</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Shi</surname>
<given-names>X. J.</given-names>
</name>
<name>
<surname>Wang</surname>
<given-names>M. M.</given-names>
</name>
<name>
<surname>Ye</surname>
<given-names>X. W.</given-names>
</name>
<etal/>
</person-group> (<year>2013</year>). <article-title>Design and synthesis of novel 1, 2, 3-triazole-dithiocarbamate hybrids as potential anticancer agents</article-title>. <source>Eur. J. Med. Chem.</source> <volume>62</volume>, <fpage>11</fpage>&#x2013;<lpage>19</lpage>. <pub-id pub-id-type="doi">10.1016/j.ejmech.2012.12.046</pub-id>
</citation>
</ref>
<ref id="B16">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Dwivedi</surname>
<given-names>G. R.</given-names>
</name>
<name>
<surname>Upadhyay</surname>
<given-names>H. C.</given-names>
</name>
<name>
<surname>Yadav</surname>
<given-names>D. K.</given-names>
</name>
<name>
<surname>Singh</surname>
<given-names>V.</given-names>
</name>
<name>
<surname>Srivastava</surname>
<given-names>S. K.</given-names>
</name>
<name>
<surname>Khan</surname>
<given-names>F.</given-names>
</name>
<etal/>
</person-group> (<year>2014</year>). <article-title>4-Hydroxy-&#x3b1;-tetralone and its derivative as drug resistance reversal agents in multi drug resistant <italic>Escherichia coli</italic>
</article-title>. <source>Chem. Biol. Drug Des.</source> <volume>83</volume>, <fpage>482</fpage>&#x2013;<lpage>492</lpage>. <pub-id pub-id-type="doi">10.1111/cbdd.12263</pub-id>
</citation>
</ref>
<ref id="B17">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>El-Sayed</surname>
<given-names>W. A.</given-names>
</name>
<name>
<surname>Alminderej</surname>
<given-names>F. M.</given-names>
</name>
<name>
<surname>Mounier</surname>
<given-names>M. M.</given-names>
</name>
<name>
<surname>Nossier</surname>
<given-names>E. S.</given-names>
</name>
<name>
<surname>Saleh</surname>
<given-names>S. M.</given-names>
</name>
<name>
<surname>Kassem</surname>
<given-names>A. F.</given-names>
</name>
</person-group> (<year>2022</year>). <article-title>Novel 1, 2, 3-triazole-coumarin hybrid glycosides and their tetrazolyl analogues: Design, anticancer evaluation and molecular docking targeting EGFR, VEGFR-2 and CDK-2</article-title>. <source>Molecules</source> <volume>27</volume>, <fpage>2047</fpage>. <pub-id pub-id-type="doi">10.3390/molecules27072047</pub-id>
</citation>
</ref>
<ref id="B18">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Emami</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Dadashpour</surname>
<given-names>S.</given-names>
</name>
</person-group> (<year>2015</year>). <article-title>Current developments of coumarin-based anti-cancer agents in medicinal chemistry</article-title>. <source>Eur. J. Med. Chem.</source> <volume>102</volume>, <fpage>611</fpage>&#x2013;<lpage>630</lpage>. <pub-id pub-id-type="doi">10.1016/j.ejmech.2015.08.033</pub-id>
</citation>
</ref>
<ref id="B19">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Fan</surname>
<given-names>Y. L.</given-names>
</name>
<name>
<surname>Ke</surname>
<given-names>X.</given-names>
</name>
<name>
<surname>Liu</surname>
<given-names>M.</given-names>
</name>
</person-group> (<year>2018</year>). <article-title>Coumarin&#x2013;triazole hybrids and their biological activities</article-title>. <source>J. Heterocycl. Chem.</source> <volume>55</volume>, <fpage>791</fpage>&#x2013;<lpage>802</lpage>. <pub-id pub-id-type="doi">10.1002/jhet.3112</pub-id>
</citation>
</ref>
<ref id="B20">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Gopalakrishnan</surname>
<given-names>A. K.</given-names>
</name>
<name>
<surname>Angamaly</surname>
<given-names>S. A.</given-names>
</name>
<name>
<surname>Velayudhan</surname>
<given-names>M. P.</given-names>
</name>
</person-group> (<year>2021</year>). <article-title>An insight into the biological properties of imidazole-based schiff bases: A review</article-title>. <source>ChemistrySelect</source> <volume>6</volume>, <fpage>10918</fpage>&#x2013;<lpage>10947</lpage>. <pub-id pub-id-type="doi">10.1002/slct.202102619</pub-id>
</citation>
</ref>
<ref id="B21">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Goud</surname>
<given-names>N. S.</given-names>
</name>
<name>
<surname>Kumar</surname>
<given-names>P.</given-names>
</name>
<name>
<surname>Bharath</surname>
<given-names>R. D.</given-names>
</name>
</person-group> (<year>2020</year>). <article-title>Recent developments of target based coumarin derivatives as potential anticancer agents</article-title>. <source>Mini Rev. Med. Chem.</source> <volume>20</volume>, <fpage>1754</fpage>&#x2013;<lpage>1766</lpage>. <pub-id pub-id-type="doi">10.2174/1389557520666200510000718</pub-id>
</citation>
</ref>
<ref id="B22">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Goud</surname>
<given-names>N. S.</given-names>
</name>
<name>
<surname>Pooladanda</surname>
<given-names>V.</given-names>
</name>
<name>
<surname>Mahammad</surname>
<given-names>G. S.</given-names>
</name>
<name>
<surname>Jakkula</surname>
<given-names>P.</given-names>
</name>
<name>
<surname>Gatreddi</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Qureshi</surname>
<given-names>I. A.</given-names>
</name>
<etal/>
</person-group> (<year>2019</year>). <article-title>Synthesis and biological evaluation of morpholines linked coumarin&#x2013;triazole hybrids as anticancer agents</article-title>. <source>Chem. Biol. Drug Des.</source> <volume>94</volume>, <fpage>1919</fpage>&#x2013;<lpage>1929</lpage>. <pub-id pub-id-type="doi">10.1111/cbdd.13578</pub-id>
</citation>
</ref>
<ref id="B23">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Hao</surname>
<given-names>S. Y.</given-names>
</name>
<name>
<surname>Feng</surname>
<given-names>S. L.</given-names>
</name>
<name>
<surname>Wang</surname>
<given-names>X. R.</given-names>
</name>
<name>
<surname>Wang</surname>
<given-names>Z.</given-names>
</name>
<name>
<surname>Chen</surname>
<given-names>S. W.</given-names>
</name>
<name>
<surname>Hui</surname>
<given-names>L.</given-names>
</name>
</person-group> (<year>2019</year>). <article-title>Novel conjugates of podophyllotoxin and coumarin: Synthesis, cytotoxicities, cell cycle arrest, binding CT DNA and inhibition of Topo II&#x3b2;</article-title>. <source>Bioorg. Med. Chem. Lett.</source> <volume>29</volume>, <fpage>2129</fpage>&#x2013;<lpage>2135</lpage>. <pub-id pub-id-type="doi">10.1016/j.bmcl.2019.06.063</pub-id>
</citation>
</ref>
<ref id="B24">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Joule</surname>
<given-names>J. A.</given-names>
</name>
</person-group> (<year>2016</year>). <article-title>Natural products containing nitrogen heterocycles&#x2014;some highlights 1990&#x2013;2015</article-title>. <source>Adv. Heterocycl. Chem.</source> <volume>119</volume>, <fpage>81</fpage>&#x2013;<lpage>106</lpage>. <pub-id pub-id-type="doi">10.1016/BS.AIHCH.2015.10.005</pub-id>
</citation>
</ref>
<ref id="B25">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Katsori</surname>
<given-names>A. M.</given-names>
</name>
<name>
<surname>Hadjipavlou-Litina</surname>
<given-names>D.</given-names>
</name>
</person-group> (<year>2014</year>). <article-title>Coumarin derivatives: An updated patent review (2012-2014)</article-title>. <source>Expert Opin. Ther. Pat.</source> <volume>24</volume>, <fpage>1323</fpage>&#x2013;<lpage>1347</lpage>. <pub-id pub-id-type="doi">10.1517/13543776.2014.972368</pub-id>
</citation>
</ref>
<ref id="B26">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Kerru</surname>
<given-names>N.</given-names>
</name>
<name>
<surname>Gummidi</surname>
<given-names>L.</given-names>
</name>
<name>
<surname>Maddila</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Gangu</surname>
<given-names>K. K.</given-names>
</name>
<name>
<surname>Jonnalagadda</surname>
<given-names>S. B.</given-names>
</name>
</person-group> (<year>2020</year>). <article-title>A review on recent advances in nitrogen-containing molecules and their biological applications</article-title>. <source>Molecules</source> <volume>25</volume>, <fpage>E1909</fpage>. <pub-id pub-id-type="doi">10.3390/molecules25081909</pub-id>
</citation>
</ref>
<ref id="B27">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Kinch</surname>
<given-names>M. S.</given-names>
</name>
<name>
<surname>Patridge</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Plummer</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Hoyer</surname>
<given-names>D.</given-names>
</name>
</person-group> (<year>2014</year>). <article-title>An analysis of FDA-approved drugs for infectious disease: Antibacterial agents</article-title>. <source>Drug Discov. Today</source> <volume>19</volume>, <fpage>1283</fpage>&#x2013;<lpage>1287</lpage>. <pub-id pub-id-type="doi">10.1016/j.drudis.2014.07.005</pub-id>
</citation>
</ref>
<ref id="B28">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Kraljevi&#x107;</surname>
<given-names>T. G.</given-names>
</name>
<name>
<surname>Harej</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Sedi&#x107;</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Paveli&#x107;</surname>
<given-names>S. K.</given-names>
</name>
<name>
<surname>Stepani&#x107;</surname>
<given-names>V.</given-names>
</name>
<name>
<surname>Drenjan&#x10d;evi&#x107;</surname>
<given-names>D.</given-names>
</name>
<etal/>
</person-group> (<year>2016</year>). <article-title>Synthesis, <italic>in vitro</italic> anticancer and antibacterial activities and <italic>in silico</italic> studies of new 4-substituted 1, 2, 3-triazole&#x2013;coumarin hybrids</article-title>. <source>Eur. J. Med. Chem.</source> <volume>124</volume>, <fpage>794</fpage>&#x2013;<lpage>808</lpage>. <pub-id pub-id-type="doi">10.1016/j.ejmech.2016.08.062</pub-id>
</citation>
</ref>
<ref id="B29">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Kumar</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Rulhania</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Jaswal</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Monga</surname>
<given-names>V.</given-names>
</name>
</person-group> (<year>2021</year>). <article-title>Recent advances in the medicinal chemistry of carbonic anhydrase inhibitors</article-title>. <source>Eur. J. Med. Chem.</source> <volume>209</volume>, <fpage>112923</fpage>. <pub-id pub-id-type="doi">10.1016/j.ejmech.2020.112923</pub-id>
</citation>
</ref>
<ref id="B30">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Kurt</surname>
<given-names>B. Z.</given-names>
</name>
<name>
<surname>Dag</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Do&#x11f;an</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>Durdagi</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Angeli</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Nocentini</surname>
<given-names>A.</given-names>
</name>
<etal/>
</person-group> (<year>2019</year>). <article-title>Synthesis, biological activity and multiscale molecular modeling studies of bis-coumarins as selective carbonic anhydrase IX and XII inhibitors with effective cytotoxicity against hepatocellular carcinoma</article-title>. <source>Bioorg. Chem.</source> <volume>87</volume>, <fpage>838</fpage>&#x2013;<lpage>850</lpage>. <pub-id pub-id-type="doi">10.1016/j.bioorg.2019.03.003</pub-id>
</citation>
</ref>
<ref id="B31">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Lacy</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>O&#x27;Kennedy</surname>
<given-names>R.</given-names>
</name>
</person-group> (<year>2005</year>). <article-title>Studies on coumarins and coumarin-related compounds to determine their therapeutic role in the treatment of cancer</article-title>. <source>Curr. Pharm. Des.</source> <volume>10</volume>, <fpage>3797</fpage>&#x2013;<lpage>3811</lpage>. <pub-id pub-id-type="doi">10.2174/1381612043382693</pub-id>
</citation>
</ref>
<ref id="B32">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Lacy</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>O&#x2019;Kennedy</surname>
<given-names>R.</given-names>
</name>
</person-group> (<year>2004</year>). <article-title>Studies on coumarins and coumarin-related compounds to determine their therapeutic role in the treatment of cancer</article-title>. <source>Curr. Pharm. Des.</source> <volume>10</volume>, <fpage>3797</fpage>&#x2013;<lpage>3811</lpage>. <pub-id pub-id-type="doi">10.2174/1381612043382693</pub-id>
</citation>
</ref>
<ref id="B33">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Liang</surname>
<given-names>T.</given-names>
</name>
<name>
<surname>Sun</surname>
<given-names>X.</given-names>
</name>
<name>
<surname>Li</surname>
<given-names>W.</given-names>
</name>
<name>
<surname>Hou</surname>
<given-names>G.</given-names>
</name>
<name>
<surname>Gao</surname>
<given-names>F.</given-names>
</name>
</person-group> (<year>2021</year>). <article-title>1, 2, 3-triazole-containing compounds as anti&#x2013;lung cancer agents: Current developments, mechanisms of action, and structure&#x2013;activity relationship</article-title>. <source>Front. Pharmacol.</source> <volume>12</volume>, <fpage>661173</fpage>. <pub-id pub-id-type="doi">10.3389/fphar.2021.661173</pub-id>
</citation>
</ref>
<ref id="B34">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Lipeeva</surname>
<given-names>A. v.</given-names>
</name>
<name>
<surname>Pokrovsky</surname>
<given-names>M. A.</given-names>
</name>
<name>
<surname>Baev</surname>
<given-names>D. S.</given-names>
</name>
<name>
<surname>Shakirov</surname>
<given-names>M. M.</given-names>
</name>
<name>
<surname>Bagryanskaya</surname>
<given-names>I. Y.</given-names>
</name>
<name>
<surname>Tolstikova</surname>
<given-names>T. G.</given-names>
</name>
<etal/>
</person-group> (<year>2015</year>). <article-title>Synthesis of 1 H -1, 2, 3-triazole linked aryl(arylamidomethyl) - dihydrofurocoumarin hybrids and analysis of their cytotoxicity</article-title>. <source>Eur. J. Med. Chem.</source> <volume>100</volume>, <fpage>119</fpage>&#x2013;<lpage>128</lpage>. <pub-id pub-id-type="doi">10.1016/j.ejmech.2015.05.016</pub-id>
</citation>
</ref>
<ref id="B35">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Masui</surname>
<given-names>K.</given-names>
</name>
<name>
<surname>Gini</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>Wykosky</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Zanca</surname>
<given-names>C.</given-names>
</name>
<name>
<surname>Mischel</surname>
<given-names>P. S.</given-names>
</name>
<name>
<surname>Furnari</surname>
<given-names>F. B.</given-names>
</name>
<etal/>
</person-group> (<year>2013</year>). <article-title>A tale of two approaches: Complementary mechanisms of cytotoxic and targeted therapy resistance may inform next-generation cancer treatments</article-title>. <source>Carcinogenesis</source> <volume>34</volume>, <fpage>725</fpage>&#x2013;<lpage>738</lpage>. <pub-id pub-id-type="doi">10.1093/carcin/bgt086</pub-id>
</citation>
</ref>
<ref id="B36">
<citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname>Matos</surname>
<given-names>M. J.</given-names>
</name>
<name>
<surname>Santana</surname>
<given-names>L.</given-names>
</name>
<name>
<surname>Uriarte</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Abreu</surname>
<given-names>O. A.</given-names>
</name>
<name>
<surname>Molina</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Yordi</surname>
<given-names>E. G.</given-names>
</name>
</person-group> (<year>2015</year>). &#x201c;<article-title>Coumarins &#x2014; an important class of phytochemicals</article-title>,&#x201d; in <source>Phytochemicals - isolation, characterisation and role in human health</source>. <pub-id pub-id-type="doi">10.5772/59982</pub-id>
</citation>
</ref>
<ref id="B37">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Mohamed</surname>
<given-names>M. F. A.</given-names>
</name>
<name>
<surname>Abuo-Rahma</surname>
<given-names>G. E. D. A.</given-names>
</name>
</person-group> (<year>2020</year>). <article-title>Molecular targets and anticancer activity of quinoline-chalcone hybrids: Literature review</article-title>. <source>RSC Adv.</source> <volume>10</volume>, <fpage>31139</fpage>&#x2013;<lpage>31155</lpage>. <pub-id pub-id-type="doi">10.1039/d0ra05594h</pub-id>
</citation>
</ref>
<ref id="B38">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Musa</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Cooperwood</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Khan</surname>
<given-names>M. O.</given-names>
</name>
</person-group> (<year>2008</year>). <article-title>A review of coumarin derivatives in pharmacotherapy of breast cancer</article-title>. <source>Curr. Med. Chem.</source> <volume>15</volume>, <fpage>2664</fpage>&#x2013;<lpage>2679</lpage>. <pub-id pub-id-type="doi">10.2174/092986708786242877</pub-id>
</citation>
</ref>
<ref id="B39">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Narsimha</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Nukala</surname>
<given-names>S. K.</given-names>
</name>
<name>
<surname>Savitha Jyostna</surname>
<given-names>T.</given-names>
</name>
<name>
<surname>Ravinder</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Srinivasa Rao</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Vasudeva Reddy</surname>
<given-names>N.</given-names>
</name>
</person-group> (<year>2020</year>). <article-title>One-pot synthesis and biological evaluation of novel 4-[3-fluoro-4-(morpholin-4-yl)]phenyl-1H-1, 2, 3-triazole derivatives as potent antibacterial and anticancer agents</article-title>. <source>J. Heterocycl. Chem.</source> <volume>57</volume>, <fpage>1655</fpage>&#x2013;<lpage>1665</lpage>. <pub-id pub-id-type="doi">10.1002/jhet.3890</pub-id>
</citation>
</ref>
<ref id="B40">
<citation citation-type="book">
<collab>National Cancer Institute</collab> (<year>2021</year>). <source>Cancer statistics - national cancer Institute</source>. <comment>Availableat: <ext-link ext-link-type="uri" xlink:href="https://www.cancer.gov/about-cancer/understanding/statistics.%20October%203">https://www.cancer.gov/about-cancer/understanding/statistics. October 3</ext-link>
</comment>.</citation>
</ref>
<ref id="B41">
<citation citation-type="book">
<collab>New Global Cancer Data: GLOBOCAN</collab> (<year>2018</year>). <source>New global cancer Data: GLOBOCAN 2018. The global cancer observatory</source>.</citation>
</ref>
<ref id="B42">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Newman</surname>
<given-names>D. J.</given-names>
</name>
<name>
<surname>Cragg</surname>
<given-names>G. M.</given-names>
</name>
</person-group> (<year>2012</year>). <article-title>Natural products as sources of new drugs over the 30 years from 1981 to 2010</article-title>. <source>J. Nat. Prod.</source> <volume>75</volume>, <fpage>311</fpage>&#x2013;<lpage>335</lpage>. <pub-id pub-id-type="doi">10.1021/np200906s</pub-id>
</citation>
</ref>
<ref id="B43">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Newman</surname>
<given-names>D. J.</given-names>
</name>
<name>
<surname>Cragg</surname>
<given-names>G. M.</given-names>
</name>
</person-group> (<year>2020</year>). <article-title>Natural products as sources of new drugs over the nearly four decades from 01/1981 to 09/2019</article-title>. <source>J. Nat. Prod.</source> <volume>83</volume>, <fpage>770</fpage>&#x2013;<lpage>803</lpage>. <pub-id pub-id-type="doi">10.1021/acs.jnatprod.9b01285</pub-id>
</citation>
</ref>
<ref id="B44">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Pastorek</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Pastorekova</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Zatovicova</surname>
<given-names>M.</given-names>
</name>
</person-group> (<year>2008</year>). <article-title>Cancer-associated carbonic anhydrases and their inhibition</article-title>. <source>Curr. Pharm. Des.</source> <volume>14</volume>, <fpage>685</fpage>&#x2013;<lpage>698</lpage>. <pub-id pub-id-type="doi">10.2174/138161208783877893</pub-id>
</citation>
</ref>
<ref id="B45">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Perabo</surname>
<given-names>F. G. E.</given-names>
</name>
<name>
<surname>Wirger</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Kamp</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Lindner</surname>
<given-names>H.</given-names>
</name>
<name>
<surname>Schmidt</surname>
<given-names>D. H.</given-names>
</name>
<name>
<surname>M&#xfc;ller</surname>
<given-names>S. C.</given-names>
</name>
<etal/>
</person-group> (<year>2004</year>). <article-title>Carboxyamido-triazole (CAI), a signal transduction inhibitor induces growth inhibition and apoptosis in bladder cancer cells by modulation of Bcl-2</article-title>. <source>Anticancer Res.</source> <volume>24</volume>, <fpage>2869</fpage>&#x2013;<lpage>2877</lpage>.</citation>
</ref>
<ref id="B46">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Pingaew</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Saekee</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Mandi</surname>
<given-names>P.</given-names>
</name>
<name>
<surname>Nantasenamat</surname>
<given-names>C.</given-names>
</name>
<name>
<surname>Prachayasittikul</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Ruchirawat</surname>
<given-names>S.</given-names>
</name>
<etal/>
</person-group> (<year>2014</year>). <article-title>Synthesis, biological evaluation and molecular docking of novel chalcone-coumarin hybrids as anticancer and antimalarial agents</article-title>. <source>Eur. J. Med. Chem.</source> <volume>85</volume>, <fpage>65</fpage>&#x2013;<lpage>76</lpage>. <pub-id pub-id-type="doi">10.1016/j.ejmech.2014.07.087</pub-id>
</citation>
</ref>
<ref id="B47">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Rawat</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Vijaya Bhaskar Reddy</surname>
<given-names>A.</given-names>
</name>
</person-group> (<year>2022</year>). <article-title>Recent advances on anticancer activity of coumarin derivatives</article-title>. <source>Eur. J. Med. Chem. Rep.</source> <volume>5</volume>, <fpage>100038</fpage>. <pub-id pub-id-type="doi">10.1016/j.ejmcr.2022.100038</pub-id>
</citation>
</ref>
<ref id="B48">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Romero</surname>
<given-names>D. H.</given-names>
</name>
<name>
<surname>Heredia</surname>
<given-names>V. E. T.</given-names>
</name>
<name>
<surname>Garc&#xed;a-Barradas</surname>
<given-names>O.</given-names>
</name>
<name>
<surname>L&#xf3;pez</surname>
<given-names>M. E. M.</given-names>
</name>
<name>
<surname>Pav&#xf3;n</surname>
<given-names>E. S.</given-names>
</name>
<name>
<surname>Narasimhan</surname>
<given-names>B.</given-names>
</name>
<etal/>
</person-group> (<year>2004</year>). <article-title>Recent advancement in imidazole as anti cancer agents : A review</article-title>. <source>Phosphorus Sulfur Silicon Relat. Elem.</source> <pub-id pub-id-type="doi">10.1016/j.tet.2004.03.016</pub-id>
</citation>
</ref>
<ref id="B49">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Sanduja</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Gupta</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Singh</surname>
<given-names>H.</given-names>
</name>
<name>
<surname>Pagare</surname>
<given-names>P. P.</given-names>
</name>
<name>
<surname>Rana</surname>
<given-names>A.</given-names>
</name>
</person-group> (<year>2020</year>). <article-title>Uracil-coumarin based hybrid molecules as potent anti-cancer and anti-bacterial agents</article-title>. <source>J. Saudi Chem. Soc.</source> <volume>24</volume>, <fpage>251</fpage>&#x2013;<lpage>266</lpage>. <pub-id pub-id-type="doi">10.1016/j.jscs.2019.12.001</pub-id>
</citation>
</ref>
<ref id="B50">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Saxena</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Upadhyay</surname>
<given-names>H. C.</given-names>
</name>
<name>
<surname>Cheema</surname>
<given-names>H. S.</given-names>
</name>
<name>
<surname>Srivastava</surname>
<given-names>S. K.</given-names>
</name>
<name>
<surname>Darokar</surname>
<given-names>M. P.</given-names>
</name>
<name>
<surname>Bawankule</surname>
<given-names>D. U.</given-names>
</name>
</person-group> (<year>2018</year>). <article-title>Antimalarial activity of phytol derivatives: <italic>In vitro</italic> and <italic>in vivo</italic> study</article-title>. <source>Med. Chem. Res.</source> <volume>27</volume>, <fpage>1345</fpage>&#x2013;<lpage>1354</lpage>. <pub-id pub-id-type="doi">10.1007/s00044-017-2132-2</pub-id>
</citation>
</ref>
<ref id="B51">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Schirrmacher</surname>
<given-names>V.</given-names>
</name>
</person-group> (<year>1985</year>). <article-title>Cancer metastasis: Experimental approaches, theoretical concepts, and impacts for treatment strategies</article-title>. <source>Adv. Cancer Res.</source> <volume>43</volume>, <fpage>1</fpage>&#x2013;<lpage>73</lpage>. <pub-id pub-id-type="doi">10.1016/S0065-230X(08)60942-2</pub-id>
</citation>
</ref>
<ref id="B52">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Shang</surname>
<given-names>X. F.</given-names>
</name>
<name>
<surname>Morris-Natschke</surname>
<given-names>S. L.</given-names>
</name>
<name>
<surname>Yang</surname>
<given-names>G. Z.</given-names>
</name>
<name>
<surname>Liu</surname>
<given-names>Y. Q.</given-names>
</name>
<name>
<surname>Guo</surname>
<given-names>X.</given-names>
</name>
<name>
<surname>Xu</surname>
<given-names>X. S.</given-names>
</name>
<etal/>
</person-group> (<year>2018</year>). <article-title>Biologically active quinoline and quinazoline alkaloids part II</article-title>. <source>Med. Res. Rev.</source> <volume>38</volume>, <fpage>1614</fpage>&#x2013;<lpage>1660</lpage>. <pub-id pub-id-type="doi">10.1002/med.21492</pub-id>
</citation>
</ref>
<ref id="B53">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Shaveta</surname>
</name>
<name>
<surname>Mishra</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Singh</surname>
<given-names>P.</given-names>
</name>
</person-group> (<year>2016</year>). <article-title>Hybrid molecules: The privileged scaffolds for various pharmaceuticals</article-title>. <source>Eur. J. Med. Chem.</source> <volume>124</volume>, <fpage>500</fpage>&#x2013;<lpage>536</lpage>. <pub-id pub-id-type="doi">10.1016/j.ejmech.2016.08.039</pub-id>
</citation>
</ref>
<ref id="B54">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Siegel</surname>
<given-names>R. L.</given-names>
</name>
<name>
<surname>Miller</surname>
<given-names>K. D.</given-names>
</name>
<name>
<surname>Fuchs</surname>
<given-names>H. E.</given-names>
</name>
<name>
<surname>Jemal</surname>
<given-names>A.</given-names>
</name>
</person-group> (<year>2022</year>). <article-title>Cancer statistics, 2022</article-title>. <source>Ca. Cancer J. Clin.</source> <volume>72</volume>, <fpage>7</fpage>&#x2013;<lpage>33</lpage>. <pub-id pub-id-type="doi">10.3322/caac.21708</pub-id>
</citation>
</ref>
<ref id="B55">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Singh</surname>
<given-names>H.</given-names>
</name>
<name>
<surname>Kumar</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Nepali</surname>
<given-names>K.</given-names>
</name>
<name>
<surname>Gupta</surname>
<given-names>M. K.</given-names>
</name>
<name>
<surname>Saxena</surname>
<given-names>A. K.</given-names>
</name>
<name>
<surname>Sharma</surname>
<given-names>S.</given-names>
</name>
<etal/>
</person-group> (<year>2016</year>). <article-title>Triazole tethered C5-curcuminoid-coumarin based molecular hybrids as novel antitubulin agents: Design, synthesis, biological investigation and docking studies</article-title>. <source>Eur. J. Med. Chem.</source> <volume>116</volume>, <fpage>102</fpage>&#x2013;<lpage>115</lpage>. <pub-id pub-id-type="doi">10.1016/j.ejmech.2016.03.050</pub-id>
</citation>
</ref>
<ref id="B56">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Singh</surname>
<given-names>H.</given-names>
</name>
<name>
<surname>Singh</surname>
<given-names>J. V.</given-names>
</name>
<name>
<surname>Bhagat</surname>
<given-names>K.</given-names>
</name>
<name>
<surname>Gulati</surname>
<given-names>H. K.</given-names>
</name>
<name>
<surname>Sanduja</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Kumar</surname>
<given-names>N.</given-names>
</name>
<etal/>
</person-group> (<year>2019</year>). <article-title>Rational approaches, design strategies, structure activity relationship and mechanistic insights for therapeutic coumarin hybrids</article-title>. <source>Bioorg. Med. Chem.</source> <volume>27</volume>, <fpage>3477</fpage>&#x2013;<lpage>3510</lpage>. <pub-id pub-id-type="doi">10.1016/j.bmc.2019.06.033</pub-id>
</citation>
</ref>
<ref id="B57">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Singh</surname>
<given-names>H.</given-names>
</name>
<name>
<surname>Singh</surname>
<given-names>J. v.</given-names>
</name>
<name>
<surname>Gupta</surname>
<given-names>M. K.</given-names>
</name>
<name>
<surname>Saxena</surname>
<given-names>A. K.</given-names>
</name>
<name>
<surname>Sharma</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Nepali</surname>
<given-names>K.</given-names>
</name>
<etal/>
</person-group> (<year>2017</year>). <article-title>Triazole tethered isatin-coumarin based molecular hybrids as novel antitubulin agents: Design, synthesis, biological investigation and docking studies</article-title>. <source>Bioorg. Med. Chem. Lett.</source> <volume>27</volume>, <fpage>3974</fpage>&#x2013;<lpage>3979</lpage>. <pub-id pub-id-type="doi">10.1016/j.bmcl.2017.07.069</pub-id>
</citation>
</ref>
<ref id="B58">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Singh</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Lomelino</surname>
<given-names>C. L.</given-names>
</name>
<name>
<surname>Mboge</surname>
<given-names>M. Y.</given-names>
</name>
<name>
<surname>Frost</surname>
<given-names>S. C.</given-names>
</name>
<name>
<surname>McKenna</surname>
<given-names>R.</given-names>
</name>
</person-group> (<year>2018</year>). <article-title>Cancer drug development of carbonic anhydrase inhibitors beyond the active site</article-title>. <source>Molecules</source> <volume>23</volume>, <fpage>E1045</fpage>. <pub-id pub-id-type="doi">10.3390/molecules23051045</pub-id>
</citation>
</ref>
<ref id="B59">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Song</surname>
<given-names>X. F.</given-names>
</name>
<name>
<surname>Fan</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Liu</surname>
<given-names>L.</given-names>
</name>
<name>
<surname>Liu</surname>
<given-names>X. F.</given-names>
</name>
<name>
<surname>Gao</surname>
<given-names>F.</given-names>
</name>
</person-group> (<year>2020</year>). <article-title>Coumarin derivatives with anticancer activities: An update</article-title>. <source>Arch. Pharm.</source> <volume>353</volume>, <fpage>e2000025</fpage>. <pub-id pub-id-type="doi">10.1002/ardp.202000025</pub-id>
</citation>
</ref>
<ref id="B60">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Stefanachi</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Leonetti</surname>
<given-names>F.</given-names>
</name>
<name>
<surname>Pisani</surname>
<given-names>L.</given-names>
</name>
<name>
<surname>Catto</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Carotti</surname>
<given-names>A.</given-names>
</name>
</person-group> (<year>2018</year>). <article-title>Coumarin: A natural, privileged and versatile scaffold for bioactive compounds</article-title>. <source>Molecules</source> <volume>23</volume>, <fpage>E250</fpage>. <pub-id pub-id-type="doi">10.3390/molecules23020250</pub-id>
</citation>
</ref>
<ref id="B61">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Sung</surname>
<given-names>H.</given-names>
</name>
<name>
<surname>Ferlay</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Siegel</surname>
<given-names>R. L.</given-names>
</name>
<name>
<surname>Laversanne</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Soerjomataram</surname>
<given-names>I.</given-names>
</name>
<name>
<surname>Jemal</surname>
<given-names>A.</given-names>
</name>
<etal/>
</person-group> (<year>2021</year>). <article-title>Global cancer statistics 2020: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries</article-title>. <source>Ca. Cancer J. Clin.</source> <volume>71</volume>, <fpage>209</fpage>&#x2013;<lpage>249</lpage>. <pub-id pub-id-type="doi">10.3322/caac.21660</pub-id>
</citation>
</ref>
<ref id="B62">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Supuran</surname>
<given-names>C. T.</given-names>
</name>
</person-group> (<year>2018</year>). <article-title>Carbonic anhydrase inhibitors as emerging agents for the treatment and imaging of hypoxic tumors</article-title>. <source>Expert Opin. Investig. Drugs</source> <volume>27</volume>, <fpage>963</fpage>&#x2013;<lpage>970</lpage>. <pub-id pub-id-type="doi">10.1080/13543784.2018.1548608</pub-id>
</citation>
</ref>
<ref id="B63">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Thacker</surname>
<given-names>P. S.</given-names>
</name>
<name>
<surname>Tiwari</surname>
<given-names>P. L.</given-names>
</name>
<name>
<surname>Angeli</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Srikanth</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Swain</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>Arifuddin</surname>
<given-names>M.</given-names>
</name>
<etal/>
</person-group> (<year>2021</year>). <article-title>Synthesis and biological evaluation of coumarin-linked 4-anilinomethyl-1, 2, 3-triazoles as potent inhibitors of carbonic anhydrases ix and xiii involved in tumorigenesis</article-title>. <source>Metabolites</source> <volume>11</volume>, <fpage>225</fpage>. <pub-id pub-id-type="doi">10.3390/metabo11040225</pub-id>
</citation>
</ref>
<ref id="B64">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Thakur</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Singla</surname>
<given-names>R.</given-names>
</name>
<name>
<surname>Jaitak</surname>
<given-names>V.</given-names>
</name>
</person-group> (<year>2015</year>). <article-title>Coumarins as anticancer agents: A review on synthetic strategies, mechanism of action and SAR studies</article-title>. <source>Eur. J. Med. Chem.</source> <volume>101</volume>, <fpage>476</fpage>&#x2013;<lpage>495</lpage>. <pub-id pub-id-type="doi">10.1016/j.ejmech.2015.07.010</pub-id>
</citation>
</ref>
<ref id="B65">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Upadhyay</surname>
<given-names>H. C.</given-names>
</name>
</person-group> (<year>2021</year>). <article-title>Coumarin-1, 2, 3-triazole hybrid molecules: An emerging scaffold for combating drug resistance</article-title>. <source>Curr. Top. Med. Chem.</source> <volume>21</volume>, <fpage>737</fpage>&#x2013;<lpage>752</lpage>. <pub-id pub-id-type="doi">10.2174/1568026621666210303145759</pub-id>
</citation>
</ref>
<ref id="B66">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Upadhyay</surname>
<given-names>H. C.</given-names>
</name>
<name>
<surname>Dwivedi</surname>
<given-names>G. R.</given-names>
</name>
<name>
<surname>Roy</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Sharma</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Darokar</surname>
<given-names>M. P.</given-names>
</name>
<name>
<surname>Srivastava</surname>
<given-names>S. K.</given-names>
</name>
</person-group> (<year>2014</year>). <article-title>Phytol derivatives as drug resistance reversal agents</article-title>. <source>ChemMedChem</source> <volume>9</volume>, <fpage>1860</fpage>&#x2013;<lpage>1868</lpage>. <pub-id pub-id-type="doi">10.1002/cmdc.201402027</pub-id>
</citation>
</ref>
<ref id="B67">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Upadhyay</surname>
<given-names>H. C.</given-names>
</name>
<name>
<surname>Jaiswal</surname>
<given-names>N.</given-names>
</name>
<name>
<surname>Tamrakar</surname>
<given-names>A. K.</given-names>
</name>
<name>
<surname>Srivastava</surname>
<given-names>A. K.</given-names>
</name>
<name>
<surname>Gupta</surname>
<given-names>N.</given-names>
</name>
<name>
<surname>Srivastava</surname>
<given-names>S. K.</given-names>
</name>
</person-group> (<year>2012</year>). <article-title>Antihyperglycemic agents from Ammannia multiflora</article-title>. <source>Nat. Product. Commun.</source> <volume>7</volume>, <fpage>1934578X1200700</fpage>&#x2013;<lpage>900</lpage>. <pub-id pub-id-type="doi">10.1177/1934578x1200700724</pub-id>
</citation>
</ref>
<ref id="B68">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Upadhyay</surname>
<given-names>H. C.</given-names>
</name>
</person-group> (<year>2019</year>). <article-title>Medicinal chemistry of alternative therapeutics: Novelty and hopes with genus ammannia</article-title>. <source>Curr. Top. Med. Chem.</source> <volume>19</volume>, <fpage>784</fpage>&#x2013;<lpage>794</lpage>. <pub-id pub-id-type="doi">10.2174/1568026619666190412101047</pub-id>
</citation>
</ref>
<ref id="B69">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Upadhyay</surname>
<given-names>H. C.</given-names>
</name>
<name>
<surname>Singh</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Prakash</surname>
<given-names>O.</given-names>
</name>
<name>
<surname>Khan</surname>
<given-names>F.</given-names>
</name>
<name>
<surname>Srivastava</surname>
<given-names>S. K.</given-names>
</name>
<name>
<surname>Bawankule</surname>
<given-names>D. U.</given-names>
</name>
</person-group> (<year>2020</year>). <article-title>QSAR, ADME and docking guided semi-synthesis and <italic>in vitro</italic> evaluation of 4-hydroxy-&#x3b1;-tetralone analogs for anti-inflammatory activity</article-title>. <source>SN Appl. Sci.</source> <volume>2</volume>, <fpage>2069</fpage>. <pub-id pub-id-type="doi">10.1007/s42452-020-03798-5</pub-id>
</citation>
</ref>
<ref id="B70">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Vagish</surname>
<given-names>C. B.</given-names>
</name>
<name>
<surname>Kumara</surname>
<given-names>K.</given-names>
</name>
<name>
<surname>Vivek</surname>
<given-names>H. K.</given-names>
</name>
<name>
<surname>Bharath</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Lokanath</surname>
<given-names>N. K.</given-names>
</name>
<name>
<surname>Ajay Kumar</surname>
<given-names>K.</given-names>
</name>
</person-group> (<year>2021</year>). <article-title>Coumarin-triazole hybrids: Design, microwave-assisted synthesis, crystal and molecular structure, theoretical and computational studies and screening for their anticancer potentials against PC-3 and DU-145</article-title>. <source>J. Mol. Struct.</source> <volume>1230</volume>, <fpage>129899</fpage>. <pub-id pub-id-type="doi">10.1016/j.molstruc.2021.129899</pub-id>
</citation>
</ref>
<ref id="B71">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Wang</surname>
<given-names>G.</given-names>
</name>
<name>
<surname>Sun</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Wu</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>Liu</surname>
<given-names>J.</given-names>
</name>
</person-group> (<year>2020</year>). <article-title>Coumarins as potential anti-drug resistant cancer agents: A mini review</article-title>. <source>Curr. Top. Med. Chem.</source> <volume>21</volume>, <fpage>1725</fpage>&#x2013;<lpage>1736</lpage>. <pub-id pub-id-type="doi">10.2174/1568026620999201113110041</pub-id>
</citation>
</ref>
<ref id="B72">
<citation citation-type="other">
<collab>WHO</collab> (<year>2021</year>). <comment>WHO &#x7c; Cancer - Fact sheet N&#xb0;297</comment>.</citation>
</ref>
<ref id="B73">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Winkler</surname>
<given-names>G. C.</given-names>
</name>
<name>
<surname>Barle</surname>
<given-names>E. L.</given-names>
</name>
<name>
<surname>Galati</surname>
<given-names>G.</given-names>
</name>
<name>
<surname>Kluwe</surname>
<given-names>W. M.</given-names>
</name>
</person-group> (<year>2014</year>). <article-title>Functional differentiation of cytotoxic cancer drugs and targeted cancer therapeutics</article-title>. <source>Regul. Toxicol. Pharmacol.</source> <volume>70</volume>, <fpage>46</fpage>&#x2013;<lpage>53</lpage>. <pub-id pub-id-type="doi">10.1016/j.yrtph.2014.06.012</pub-id>
</citation>
</ref>
<ref id="B74">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Wu</surname>
<given-names>Y.</given-names>
</name>
<name>
<surname>Xu</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Liu</surname>
<given-names>Y.</given-names>
</name>
<name>
<surname>Zeng</surname>
<given-names>Y.</given-names>
</name>
<name>
<surname>Wu</surname>
<given-names>G.</given-names>
</name>
</person-group> (<year>2020</year>). <article-title>A review on anti-tumor mechanisms of coumarins</article-title>. <source>Front. Oncol.</source> <volume>10</volume>, <fpage>592853</fpage>. <pub-id pub-id-type="doi">10.3389/fonc.2020.592853</pub-id>
</citation>
</ref>
<ref id="B75">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Xu</surname>
<given-names>Z.</given-names>
</name>
<name>
<surname>Zhao</surname>
<given-names>S. J.</given-names>
</name>
<name>
<surname>Liu</surname>
<given-names>Y.</given-names>
</name>
</person-group> (<year>2019a</year>). <article-title>1, 2, 3-Triazole-containing hybrids as potential anticancer agents: Current developments, action mechanisms and structure-activity relationships</article-title>. <source>Eur. J. Med. Chem.</source> <volume>183</volume>, <fpage>111700</fpage>. <pub-id pub-id-type="doi">10.1016/j.ejmech.2019.111700</pub-id>
</citation>
</ref>
<ref id="B76">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Xu</surname>
<given-names>Z.</given-names>
</name>
<name>
<surname>Zhao</surname>
<given-names>S. J.</given-names>
</name>
<name>
<surname>Lv</surname>
<given-names>Z. S.</given-names>
</name>
<name>
<surname>Gao</surname>
<given-names>F.</given-names>
</name>
<name>
<surname>Wang</surname>
<given-names>Y. L.</given-names>
</name>
<name>
<surname>Zhang</surname>
<given-names>F.</given-names>
</name>
<etal/>
</person-group> (<year>2019b</year>). <article-title>Design, synthesis, and evaluation of tetraethylene glycol-tethered isatin&#x2013;1, 2, 3-triazole&#x2013;coumarin hybrids as novel anticancer agents</article-title>. <source>J. Heterocycl. Chem.</source> <volume>56</volume>, <fpage>1127</fpage>&#x2013;<lpage>1132</lpage>. <pub-id pub-id-type="doi">10.1002/jhet.3475</pub-id>
</citation>
</ref>
<ref id="B77">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Yedjou</surname>
<given-names>C. G.</given-names>
</name>
<name>
<surname>Mbemi</surname>
<given-names>A. T.</given-names>
</name>
<name>
<surname>Noubissi</surname>
<given-names>F.</given-names>
</name>
<name>
<surname>Tchounwou</surname>
<given-names>S. S.</given-names>
</name>
<name>
<surname>Tsabang</surname>
<given-names>N.</given-names>
</name>
<name>
<surname>Payton</surname>
<given-names>M.</given-names>
</name>
<etal/>
</person-group> (<year>2019</year>). <article-title>Prostate cancer disparity, chemoprevention, and treatment by specific medicinal plants</article-title>. <source>Nutrients</source> <volume>11</volume>, <fpage>E336</fpage>. <pub-id pub-id-type="doi">10.3390/nu11020336</pub-id>
</citation>
</ref>
<ref id="B78">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Zaid</surname>
<given-names>H.</given-names>
</name>
<name>
<surname>Silbermann</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Amash</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Gincel</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Abdel-Sattar</surname>
<given-names>E.</given-names>
</name>
<name>
<surname>Sarikahya</surname>
<given-names>N. B.</given-names>
</name>
</person-group> (<year>2017</year>). <article-title>Medicinal plants and natural active compounds for cancer chemoprevention/chemotherapy</article-title>. <source>Evid. Based. Complement. Altern. Med.</source> <volume>2017</volume>, <fpage>7952417</fpage>. <pub-id pub-id-type="doi">10.1155/2017/7952417</pub-id>
</citation>
</ref>
<ref id="B79">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Zengin Kurt</surname>
<given-names>B.</given-names>
</name>
<name>
<surname>Sonmez</surname>
<given-names>F.</given-names>
</name>
<name>
<surname>Ozturk</surname>
<given-names>D.</given-names>
</name>
<name>
<surname>Akdemir</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Angeli</surname>
<given-names>A.</given-names>
</name>
<name>
<surname>Supuran</surname>
<given-names>C. T.</given-names>
</name>
</person-group> (<year>2019</year>). <article-title>Synthesis of coumarin-sulfonamide derivatives and determination of their cytotoxicity, carbonic anhydrase inhibitory and molecular docking studies</article-title>. <source>Eur. J. Med. Chem.</source> <volume>183</volume>, <fpage>111702</fpage>. <pub-id pub-id-type="doi">10.1016/j.ejmech.2019.111702</pub-id>
</citation>
</ref>
<ref id="B80">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Zhang</surname>
<given-names>W.</given-names>
</name>
<name>
<surname>Li</surname>
<given-names>Z.</given-names>
</name>
<name>
<surname>Zhou</surname>
<given-names>M.</given-names>
</name>
<name>
<surname>Wu</surname>
<given-names>F.</given-names>
</name>
<name>
<surname>Hou</surname>
<given-names>X.</given-names>
</name>
<name>
<surname>Luo</surname>
<given-names>H.</given-names>
</name>
<etal/>
</person-group> (<year>2014</year>). <article-title>Synthesis and biological evaluation of 4-(1, 2, 3-triazol-1-yl)coumarin derivatives as potential antitumor agents</article-title>. <source>Bioorg. Med. Chem. Lett.</source> <volume>24</volume>, <fpage>799</fpage>&#x2013;<lpage>807</lpage>. <pub-id pub-id-type="doi">10.1016/j.bmcl.2013.12.095</pub-id>
</citation>
</ref>
<ref id="B81">
<citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname>Zugazagoitia</surname>
<given-names>J.</given-names>
</name>
<name>
<surname>Guedes</surname>
<given-names>C.</given-names>
</name>
<name>
<surname>Ponce</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Ferrer</surname>
<given-names>I.</given-names>
</name>
<name>
<surname>Molina-Pinelo</surname>
<given-names>S.</given-names>
</name>
<name>
<surname>Paz-Ares</surname>
<given-names>L.</given-names>
</name>
</person-group> (<year>2016</year>). <article-title>Current challenges in cancer treatment</article-title>. <source>Clin. Ther.</source> <volume>38</volume>, <fpage>1551</fpage>&#x2013;<lpage>1566</lpage>. <pub-id pub-id-type="doi">10.1016/j.clinthera.2016.03.026</pub-id>
</citation>
</ref>
</ref-list>
</back>
</article>