{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T00:39:21Z","timestamp":1759970361236,"version":"build-2065373602"},"reference-count":27,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2025,1,15]],"date-time":"2025-01-15T00:00:00Z","timestamp":1736899200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Institute of Pharmaceutical Life Sciences, Aichi Gakuin University"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Oxazole, a versatile and significant heteroarene, serves as a bridge between synthetic organic chemistry and applications in the medicinal, pharmaceutical, and industrial fields. Polycyclic aromatic compounds with amino groups substituted at the 2-position of an oxazole, such as 2-aminonaphthoxazoles, are expected to be functional probes, but their synthetic methods are extremely limited. Herein, we describe electrochemical reactions of 3-amino-2-naphthol or 3-amino-2-anthracenol and isothiocyanates in DMSO, using a graphite electrode as an anode and a platinum electrode as a cathode in the presence of potassium iodide (KI), which afford N-arylnaphtho- and N-arylanthra[2,3-d]oxazol-2-amines via cyclodesulfurization. This reaction is the first example of synthesis of 2-aminoxazole-based polycyclic compounds using an electrochemical reaction. An examination of the spectroscopic properties of polycyclic oxazoles revealed that the \u03bbabs value of the tetracyclic oxazoles was redshifted relative to that of the tricyclic oxazoles. Moreover, synthesized naphthalene\/anthracene-fused tricyclic and tetracyclic oxazoles exhibited extended \u03c0-conjugated skeletons and fluoresced in the 340\u2013430 nm region in chloroform.<\/jats:p>","DOI":"10.3390\/molecules30020319","type":"journal-article","created":{"date-parts":[[2025,1,15]],"date-time":"2025-01-15T04:42:08Z","timestamp":1736916128000},"page":"319","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Synthesis and Optical Properties of N-Arylnaphtho- and Anthra[2,3-d]oxazol-2-amines"],"prefix":"10.3390","volume":"30","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8677-2807","authenticated-orcid":false,"given":"Yuki","family":"Murata","sequence":"first","affiliation":[{"name":"School of Pharmaceutical Sciences, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya 464-8650, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Masato","family":"Kawakubo","sequence":"additional","affiliation":[{"name":"School of Pharmaceutical Sciences, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya 464-8650, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ayumi","family":"Maruyama","sequence":"additional","affiliation":[{"name":"School of Pharmaceutical Sciences, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya 464-8650, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mio","family":"Matsumura","sequence":"additional","affiliation":[{"name":"School of Pharmaceutical Sciences, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya 464-8650, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9232-5205","authenticated-orcid":false,"given":"Shuji","family":"Yasuike","sequence":"additional","affiliation":[{"name":"School of Pharmaceutical Sciences, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya 464-8650, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1916","DOI":"10.2174\/1568026620666200624161151","article-title":"Current scenario of 1,3-oxazole derivatives for anticancer activity","volume":"20","author":"Yan","year":"2020","journal-title":"Curr. Top. Med. Chem."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"778","DOI":"10.1016\/j.ejmech.2014.11.064","article-title":"Benzoxazoles and oxazolopyridines in medicinal chemistry studies","volume":"97","author":"Demmer","year":"2015","journal-title":"Eur. J. Med. Chem."},{"key":"ref_3","first-page":"16","article-title":"Benzoxazole: The molecule of diverse pharmacological importance","volume":"7","author":"Kaur","year":"2015","journal-title":"Int. J. Pharm. Pharm. Sci."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1338","DOI":"10.1002\/ajoc.201500235","article-title":"Recent advances in the development of pharmacologically active compounds that contain a benzoxazole scaffold","volume":"4","author":"Singh","year":"2015","journal-title":"Asian J. Org. Chem."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1016\/j.dyepig.2016.07.012","article-title":"An overview on sensing materials depending on the electromagnetic spectra region applied","volume":"135","author":"Oliveira","year":"2016","journal-title":"Dye. Pigment."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1937","DOI":"10.1016\/j.bmc.2016.03.004","article-title":"Synthetic approaches to the 2014 new drugs","volume":"24","author":"Flick","year":"2016","journal-title":"Bioorg. Med. Chem."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"118","DOI":"10.4103\/0976-500X.155496","article-title":"Suvorexant: The first orexin receptor antagonist to treat insomnia","volume":"6","author":"Dubey","year":"2015","journal-title":"J. Pharmacol. Pharmacother."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"7580","DOI":"10.1016\/j.bmc.2010.08.047","article-title":"Synthesis and evaluation of benzoxazole derivatives as 5-lipoxygenase inhibitors","volume":"18","author":"Song","year":"2010","journal-title":"Bioorg. Med. Chem."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1592","DOI":"10.1016\/j.bmcl.2014.01.058","article-title":"2-Amino-7-substituted benzoxazole analogs as potent RSK2 inhibitors","volume":"24","author":"Costales","year":"2014","journal-title":"Bioorg. Med. Chem. Lett."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"5374","DOI":"10.1016\/j.bmc.2016.08.061","article-title":"Synthesis, biological evaluation and molecular docking study of N-arylbenzo[d]oxazol-2-amines as potential \u03b1-glucosidase inhibitors","volume":"24","author":"Wang","year":"2016","journal-title":"Bioorg. Med. Chem."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"2621","DOI":"10.1002\/slct.202100201","article-title":"Cyclodesulfurization: An enabling protocol for synthesis of various heterocycles","volume":"6","author":"Kadagathur","year":"2021","journal-title":"ChemstrySelect"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"e202400076","DOI":"10.1002\/ajoc.202400076","article-title":"Hypervalent iodine mediated synthesis of 2-aminobenzazoles and 2-aminobenzothiazoles","volume":"13","author":"Gu","year":"2024","journal-title":"Asian J. Org. Chem."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"e202400223","DOI":"10.1002\/ajoc.202400223","article-title":"HFIP-mediated cyclodesulfurization approach for the synthesis of 2-aminobenzoxazole and 2-aminobenzothiazole derivatives","volume":"13","author":"Kant","year":"2024","journal-title":"Asian J. Org. Chem."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"12600","DOI":"10.1039\/D0CC05387B","article-title":"Protection against chemical submission: Naked-eye detection of \u03b3-hydroxybutyric acid (GHB) in soft drinks and alcoholic beverages","volume":"56","author":"Costero","year":"2020","journal-title":"Chem. Commun."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"18","DOI":"10.1016\/j.jorganchem.2018.01.041","article-title":"One-pot reaction for the synthesis of N-substituted 2-aminobenzoxazoles using triphenylbismuth dichloride as cyclodesulfurization reagent","volume":"859","author":"Murata","year":"2018","journal-title":"J. Organomet. Chem."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"7425","DOI":"10.1039\/D0OB01431A","article-title":"A Cu2O\/TBAB-promoted approach to synthesize heteroaromatic 2-amines via one-pot cyclization of aryl isothiocyanates with ortho-substituted amines in water","volume":"18","author":"Zhang","year":"2020","journal-title":"Org. Biomol. Chem."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"154510","DOI":"10.1016\/j.tetlet.2023.154510","article-title":"Synthesis of 2-aminobenzoxazoles from elemental sulfur mediated cyclization of 2-aminophenols and aryl isothiocyanates","volume":"122","author":"Tran","year":"2023","journal-title":"Tetrahedron Lett."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"8047","DOI":"10.1039\/D1GC02533C","article-title":"Environment-friendly and efficient synthesis of 2-aminobenzo-xazoles and 2-aminobenzothiazoles catalyzed by Vitreoscilla hemoglobin incorporating a cobalt porphyrin cofactor","volume":"23","author":"Xu","year":"2021","journal-title":"Green Chem."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"2012","DOI":"10.1002\/ejoc.201901635","article-title":"Catalytic electrosynthesis of N,O-heterocycles\u2014Recent advances","volume":"2020","author":"Listratova","year":"2020","journal-title":"Eur. J. Org. Chem."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"2455","DOI":"10.1055\/s-0037-1611797","article-title":"Recent advances in electrochemistry for the synthesis of N-heterocycles","volume":"51","author":"Sbei","year":"2019","journal-title":"Synthesis"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"4485","DOI":"10.1021\/acs.chemrev.7b00271","article-title":"Use of electrochemistry in the synthesis of heterocyclic structures","volume":"118","author":"Jiang","year":"2018","journal-title":"Chem. Rev."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"5189","DOI":"10.1039\/D1GC01131F","article-title":"Electrochemical NaI\/NaCl-mediated one-pot synthesis of 2-aminobenzoxazoles in aqueous media via tandem addition\u2013cyclization","volume":"23","author":"Huynh","year":"2021","journal-title":"Green Chem."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"2375","DOI":"10.1039\/C8OB00063H","article-title":"Recent advances in iodine mediated electrochemical oxidative cross-coupling","volume":"16","author":"Liu","year":"2018","journal-title":"Org. Biomol. Chem."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"1915","DOI":"10.1021\/acs.analchem.5b04332","article-title":"Electrochemistry of iodide, iodine, and iodine monochloride in chloride containing nonhaloaluminate ionic liquids","volume":"88","author":"Bentlety","year":"2016","journal-title":"Anal. Chem."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"8781","DOI":"10.1039\/C8CC04543G","article-title":"Convenient synthesis of selenyl-indoles via iodide ion-catalyzed electrochemical C\u2013H selenation","volume":"54","author":"Zhang","year":"2018","journal-title":"Chem. Commun."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1107","DOI":"10.1351\/pac198860071107","article-title":"Reference materials for fluorescence measurement","volume":"60","author":"Eaton","year":"1988","journal-title":"Pure Appl. Chem."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"11474","DOI":"10.1021\/acs.langmuir.6b03055","article-title":"Self-assembled monolayers of pseudo-C2v-Symmetric, low-band-gap areneoxazolethiolates on gold surfaces","volume":"32","author":"Partes","year":"2016","journal-title":"Langmuir"}],"container-title":["Molecules"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1420-3049\/30\/2\/319\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,8]],"date-time":"2025-10-08T10:29:03Z","timestamp":1759919343000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1420-3049\/30\/2\/319"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,1,15]]},"references-count":27,"journal-issue":{"issue":"2","published-online":{"date-parts":[[2025,1]]}},"alternative-id":["molecules30020319"],"URL":"https:\/\/doi.org\/10.3390\/molecules30020319","relation":{},"ISSN":["1420-3049"],"issn-type":[{"type":"electronic","value":"1420-3049"}],"subject":[],"published":{"date-parts":[[2025,1,15]]}}}