{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,18]],"date-time":"2026-04-18T09:31:28Z","timestamp":1776504688220,"version":"3.51.2"},"reference-count":41,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,1,24]],"date-time":"2023-01-24T00:00:00Z","timestamp":1674518400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>The spectral properties of several azulene-oxazolone derivatives containing a phenyloxazolone moiety linked to a substituted azulene ring via a C=C double bond were studied in different solvents of varying polarity. The solvatochromism and the ability of azulene-oxazolone derivatives to recognize heavy metal ions were investigated. In order to estimate the contribution of the non-specific and specific solute\u2013solvent interactions, multiple linear regression analysis using Kamlet\u2013Taft, Catalan and Laurence parameters was applied. These azulene derivatives demonstrate positive solvatochromism. The methyl and isopropyl substituents at the seven-membered azulene ring determine the highest red shifts of the absorption maxima of these azulenyl-vinyl-oxazolones. According to Catalan and Laurence models, the solvent polarizability is a more significant parameter in describing the solvatochromic properties of the azulene-oxazolone derivatives. The azulene-oxazolone compounds under study showed a good response to heavy metal cations (Cd2+, Hg2+, Cu2+ and Pb2+).<\/jats:p>","DOI":"10.3390\/sym15020327","type":"journal-article","created":{"date-parts":[[2023,1,25]],"date-time":"2023-01-25T03:53:18Z","timestamp":1674618798000},"page":"327","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Solvent Effects and Metal Ion Recognition in Several Azulenyl-Vinyl-Oxazolones"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9432-5479","authenticated-orcid":false,"given":"Mihaela","family":"Homocianu","sequence":"first","affiliation":[{"name":"Petru Poni Institute of Macromolecular Chemistry, Grigore Ghica Voda Alley, 41A, 700487 Iasi, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anton","family":"Airinei","sequence":"additional","affiliation":[{"name":"Petru Poni Institute of Macromolecular Chemistry, Grigore Ghica Voda Alley, 41A, 700487 Iasi, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9226-0170","authenticated-orcid":false,"given":"Ovidiu-Teodor","family":"Matica","sequence":"additional","affiliation":[{"name":"Doctoral School of Chemical Engineering and Biotechnologies, Faculty of Chemical Engineering and Biotechnologies, University \u201cPolitehnica\u201d of Bucharest, Gheorghe Polizu 1-7, Sector 1, 011061 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mihaela","family":"Cristea","sequence":"additional","affiliation":[{"name":"\u201cC.D. Nenitzescu\u201d Institute of Organic and Supramolecular Chemistry, Romanian Academy, 060023 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eleonora-Mihaela","family":"Ungureanu","sequence":"additional","affiliation":[{"name":"Doctoral School of Chemical Engineering and Biotechnologies, Faculty of Chemical Engineering and Biotechnologies, University \u201cPolitehnica\u201d of Bucharest, Gheorghe Polizu 1-7, Sector 1, 011061 Bucharest, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"945","DOI":"10.1002\/cplu.201700039","article-title":"Application of azulene in constructing organic optoelectronic materials: New tricks for an old dog","volume":"82","author":"Xin","year":"2017","journal-title":"ChemPlusChem"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"3994","DOI":"10.1016\/j.tetlet.2018.09.053","article-title":"Conformational analysis of N-aryl-N-(2-azulenyl)acetamides","volume":"59","author":"Ito","year":"2018","journal-title":"Tetrahedron Lett."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1097","DOI":"10.1016\/j.cclet.2016.05.005","article-title":"Azulene-based organic functional molecules for optoelectronics","volume":"27","author":"Dong","year":"2016","journal-title":"Chin. 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