{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,22]],"date-time":"2026-10-22T20:13:32Z","timestamp":1792700012453,"version":"4.5.0"},"reference-count":33,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2025,10,2]],"date-time":"2025-10-02T00:00:00Z","timestamp":1759363200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union-NextGenerationEU","award":["SUMMIT BG-RRP-2.004-0008 C01 (70-123-216\/12.02.2024)"],"award-info":[{"award-number":["SUMMIT BG-RRP-2.004-0008 C01 (70-123-216\/12.02.2024)"]}]}],"content-domain":{"domain":["www.mdpi.com"],"crossmark-restriction":true},"short-container-title":["Molecules"],"abstract":"<jats:p>Using an environmentally friendly approach, we successfully synthesized an asymmetric monomethine cyanine dye, 7-chloro-1-ethyl-4-((3-ethylbenzo[d]thiazol-2(3H)-ylidene)methyl) quinolin-1-ium iodide, named CHLoris (CHL), via a modified Knoevenagel-type condensation. The reaction was carried out mechanochemically in an ethanol\u2013water medium using 1-ethyl-2-methylbenzothiazolium iodide and 4,7-dichloro-1-ethylquinolin-1-ium iodide in the presence of sodium carbonate as a base and catalytic amounts of H\u00fcnig\u2019s base. The UV\/VIS absorption spectra of CHL in both the buffer solution and ethanol revealed the formation of aggregates in aqueous media. Density Functional Theory (DFT) and Time-Dependent DFT (TDDFT) calculations were employed to support the experimental findings further and provide insights into the self-association behavior of CHL in an aqueous solution. The photophysical properties of the dye were examined in the presence of DNA and RNA, and its performance was compared to that of the commercial dye Thiazole Orange (TO) under identical conditions. The results show that CHL is more sensitive towards RNA.<\/jats:p>","DOI":"10.3390\/molecules30193966","type":"journal-article","created":{"date-parts":[[2025,10,2]],"date-time":"2025-10-02T15:07:48Z","timestamp":1759417668000},"page":"3966","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Mechanochemical Approach to a Monocationic Asymmetric Monomethine Cyanine Dye for Nucleic Acid Analysis and Visualization"],"prefix":"10.3390","volume":"30","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9344-9282","authenticated-orcid":false,"given":"Diana","family":"Cheshmedzhieva","sequence":"first","affiliation":[{"name":"Faculty of Chemistry and Pharmacy, Sofia University \u201cSt. Kliment Ohridski\u201d, 1 J. Bourchier Ave., 1164 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nadezhda","family":"Bozova","sequence":"additional","affiliation":[{"name":"Faculty of Chemistry and Pharmacy, Sofia University \u201cSt. Kliment Ohridski\u201d, 1 J. Bourchier Ave., 1164 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3911-7287","authenticated-orcid":false,"given":"Sonia","family":"Ilieva","sequence":"additional","affiliation":[{"name":"Faculty of Chemistry and Pharmacy, Sofia University \u201cSt. Kliment Ohridski\u201d, 1 J. Bourchier Ave., 1164 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2297-1161","authenticated-orcid":false,"given":"Christo","family":"Novakov","sequence":"additional","affiliation":[{"name":"Institute of Polymers, Bulgarian Academy of Sciences, Akad. G. Bonchev St., bl 103A, 1113 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2199-5644","authenticated-orcid":false,"given":"Aleksey","family":"Vasilev","sequence":"additional","affiliation":[{"name":"Faculty of Chemistry and Pharmacy, Sofia University \u201cSt. Kliment Ohridski\u201d, 1 J. Bourchier Ave., 1164 Sofia, Bulgaria"},{"name":"Institute of Polymers, Bulgarian Academy of Sciences, Akad. G. Bonchev St., bl 103A, 1113 Sofia, Bulgaria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,2]]},"reference":[{"key":"ref_1","unstructured":"Johnson, I., and Spence, M. (2010). A guide to fluorescent probes and labeling technologies. Molecular Probes, Thermo-Fisher. [11th ed.]."},{"key":"ref_2","unstructured":"Kim, S.-H. (2006). Functional Dyes, Elsevier. 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