{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,4]],"date-time":"2026-03-04T21:28:29Z","timestamp":1772659709248,"version":"3.50.1"},"reference-count":35,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2020,5,28]],"date-time":"2020-05-28T00:00:00Z","timestamp":1590624000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The synthesis of new phenanthr[9,10-e][1,3]oxazines was achieved by the direct coupling of 9-phenanthrol with cyclic imines in the modified aza-Friedel\u2013Crafts reaction followed by the ring closure of the resulting bifunctional aminophenanthrols with formaldehyde. Aminophenanthrol-type Mannich bases were synthesised and transformed to phenanthr[9,10-e][1,3]oxazines via [4 + 2] cycloaddition. Detailed NMR structural analyses of the new polyheterocycles as well as conformational studies including Density Functional Theory (DFT) modelling were performed. The relative stability of ortho-quinone methides (o-QMs) was calculated, the geometries obtained were compared with the experimentally determined NMR structures, and thereby, the regioselectivity of the reactions has been assigned.<\/jats:p>","DOI":"10.3390\/molecules25112524","type":"journal-article","created":{"date-parts":[[2020,5,29]],"date-time":"2020-05-29T02:16:27Z","timestamp":1590718587000},"page":"2524","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Synthesis and Conformational Analysis of Naphthoxazine-Fused Phenanthrene Derivatives"],"prefix":"10.3390","volume":"25","author":[{"given":"Khadija","family":"Belasri","sequence":"first","affiliation":[{"name":"Institute of Pharmaceutical Chemistry and MTA-SZTE Stereochemistry Research Group, Hungarian Academy of Sciences, University of Szeged, E\u00f6tv\u00f6s u. 6, H-6720 Szeged, Hungary"},{"name":"Institute of Pharmaceutical Chemistry, University of Szeged, Interdisciplinary excellence center, H-6720 Szeged, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Leila","family":"Topal","sequence":"additional","affiliation":[{"name":"Institute of Pharmaceutical Chemistry and MTA-SZTE Stereochemistry Research Group, Hungarian Academy of Sciences, University of Szeged, E\u00f6tv\u00f6s u. 6, H-6720 Szeged, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1639-4959","authenticated-orcid":false,"given":"Matthias","family":"Heydenreich","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, D-14476 Potsdam (Golm), Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andreas","family":"Koch","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, D-14476 Potsdam (Golm), Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Erich","family":"Kleinpeter","sequence":"additional","affiliation":[{"name":"Department of Chemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, D-14476 Potsdam (Golm), Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1066-5287","authenticated-orcid":false,"given":"Ferenc","family":"F\u00fcl\u00f6p","sequence":"additional","affiliation":[{"name":"Institute of Pharmaceutical Chemistry and MTA-SZTE Stereochemistry Research Group, Hungarian Academy of Sciences, University of Szeged, E\u00f6tv\u00f6s u. 6, H-6720 Szeged, Hungary"},{"name":"Institute of Pharmaceutical Chemistry, University of Szeged, Interdisciplinary excellence center, H-6720 Szeged, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8571-5229","authenticated-orcid":false,"given":"Istv\u00e1n","family":"Szatm\u00e1ri","sequence":"additional","affiliation":[{"name":"Institute of Pharmaceutical Chemistry and MTA-SZTE Stereochemistry Research Group, Hungarian Academy of Sciences, University of Szeged, E\u00f6tv\u00f6s u. 6, H-6720 Szeged, Hungary"},{"name":"Institute of Pharmaceutical Chemistry, University of Szeged, Interdisciplinary excellence center, H-6720 Szeged, Hungary"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,5,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1697","DOI":"10.1038\/bjp.2008.38","article-title":"9-Phenanthrol Inhibits Human TRPM4 but not TRPM5 Cationic Channels","volume":"153","author":"Grand","year":"2008","journal-title":"Br. 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