{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,17]],"date-time":"2026-10-17T21:14:08Z","timestamp":1792271648137,"version":"4.4.0"},"reference-count":43,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2026,2,8]],"date-time":"2026-02-08T00:00:00Z","timestamp":1770508800000},"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>In addition to well-known traditional synthetic illicit drugs like cocaine, amphetamines, and heroin, an increasing number of new psychoactive substances (NPS) are appearing on the global drug market. Among them, cathinones represent a prominent class. These amphetamine-like compounds contain a stereogenic center, resulting in the possible presence of two enantiomers. Pure enantiomers of cathinone derivatives are not commonly available, and their production is cost-intensive. Thus, there is very little knowledge about the possible distinct effects of single enantiomers of cathinones. The objective of this study was to evaluate the stability of a set of eight cathinone derivatives, namely 3-methylethcathinone, 3-methylmethcathinone, 4-methylethcathinone, 4-methylmethcathinone, ethylone, 3,4-trimethylene-\u03b1-ethylaminovalerophenone, 3,4-tetramethylene-\u03b1-pyrrolidinovalerophenone, and 3,4-trimethylene-\u03b1-pyrrolidinobutiophenone, over a six-month period. Any racemization that may have occurred under different storage and solution conditions was monitored and compared. Pure enantiomeric fractions were collected on a multi-milligram scale using semi-preparative HPLC under isocratic normal-phase conditions. A Phenomenex Lux\u00ae i-Cellulose-5, 5 \u03bcm 250 \u00d7 10 mm column containing cellulose tris(3,5-dichlorophenylcarbamate) served as the chiral selector. The tests showed that aqueous conditions, pH, temperature, chemical structure, sunlight, and oxygen influence compound stability. The long-term storage of cathinone derivative enantiomers was found to be optimal as solids under deep-freezing conditions or in a slightly acidified solvent where they are protected from air and light.<\/jats:p>","DOI":"10.3390\/molecules31040587","type":"journal-article","created":{"date-parts":[[2026,2,9]],"date-time":"2026-02-09T12:42:42Z","timestamp":1770640962000},"page":"587","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Isolation, Characterization, and Stability Assessment of Pure Enantiomers of Cathinone Derivatives via Semi-Preparative HPLC-UV Using a Phenomenex Lux\u00ae 5 Column"],"prefix":"10.3390","volume":"31","author":[{"given":"Stefanie","family":"Handl","sequence":"first","affiliation":[{"name":"Department of Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences, University of Graz, Schubertstra\u00dfe 1, 8010 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Katrin","family":"Stelzeneder","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences, University of Graz, Schubertstra\u00dfe 1, 8010 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Annaluna","family":"Ravelli","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences, University of Graz, Schubertstra\u00dfe 1, 8010 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0055-660X","authenticated-orcid":false,"given":"Martin G.","family":"Schmid","sequence":"additional","affiliation":[{"name":"Department of Pharmaceutical Chemistry, Institute of Pharmaceutical Sciences, University of Graz, Schubertstra\u00dfe 1, 8010 Graz, Austria"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,2,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"757","DOI":"10.1007\/s00204-014-1278-7","article-title":"Raising awareness of new psychoactive substances: Chemical analysis and in vitro toxicity screening of \u2018legal high\u2019 packages containing synthetic cathinones","volume":"89","author":"Valente","year":"2015","journal-title":"Arch. 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