{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,23]],"date-time":"2025-12-23T10:45:13Z","timestamp":1766486713986,"version":"build-2065373602"},"reference-count":31,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2025,1,2]],"date-time":"2025-01-02T00:00:00Z","timestamp":1735776000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>O-Methyldehydroserine, \u0394Ser(Me), is a non-standard \u03b1,\u03b2-dehydroamino acid, which occurs naturally in Cyrmenins with potential pharmaceutical application. The C-terminal part and the side chain of the \u0394Ser(Me) residue constitute the \u03b2-methoxyacrylate unit, responsible for antifungal activity of Cyrmenins. The short model, Ac-\u0394Ser(Me)-OMe, was analyzed considering the geometrical isomer Z (1) and E (2). The Ramachandran diagrams were created for both isomers, using quantum chemical calculations, to show possible conformations for isolated molecules (in vacuo), in weakly polar (chloroform) and polar (water) environments. The Ac-(Z)-\u0394Ser(Me)-OMe (1) was synthesized and the single-crystal X-ray diffraction analysis together with FT-IR spectra were performed. The detailed analysis of the conformations of the (Z)-\u0394Ser(Me) residue is presented considering the intra- and intermolecular interactions as well as their influence on the \u03b2-methoxyacrylate part. It is concluded that the \u03b2-methoxyacrylate structural motif is able to maintain a planar geometry, crucial for biological activity, regardless of the conformation adopted by O-methyldehydroserine.<\/jats:p>","DOI":"10.3390\/ijms26010340","type":"journal-article","created":{"date-parts":[[2025,1,2]],"date-time":"2025-01-02T07:44:53Z","timestamp":1735803893000},"page":"340","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Insight into the Structure of Antifungal Cyrmenins: Conformational Studies of Unique Dehydroamino Acid, O-Methyldehydroserine"],"prefix":"10.3390","volume":"26","author":[{"given":"Karolina","family":"Bana\u015b","sequence":"first","affiliation":[{"name":"Faculty of Chemistry and Pharmacy, University of Opole, Oleska 48, 45-052 Opole, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pawe\u0142","family":"Lenartowicz","sequence":"additional","affiliation":[{"name":"Faculty of Chemistry and Pharmacy, University of Opole, Oleska 48, 45-052 Opole, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7854-0141","authenticated-orcid":false,"given":"Monika","family":"Sta\u015b-Bobis","sequence":"additional","affiliation":[{"name":"Faculty of Chemistry and Pharmacy, University of Opole, Oleska 48, 45-052 Opole, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"B\u0142a\u017cej","family":"Dziuk","sequence":"additional","affiliation":[{"name":"Faculty of Chemistry, Wroclaw University of Science and Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw, Poland"},{"name":"Faculty of Chemistry, University of Wroclaw, Joliot-Curie 14, 50-383 Wroclaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1686-5215","authenticated-orcid":false,"given":"Dawid","family":"Siod\u0142ak","sequence":"additional","affiliation":[{"name":"Faculty of Chemistry and Pharmacy, University of Opole, Oleska 48, 45-052 Opole, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,1,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"431","DOI":"10.1002\/ejoc.200300367","article-title":"Cyrmenins, Novel Antifungal Peptides Containing a Nitrogen-Linked \u03b2-Methoxyacrylate Pharmacophore: Isolation and Structural Elucidation","volume":"2004","author":"Leibold","year":"2004","journal-title":"Eur. 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