{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,19]],"date-time":"2026-03-19T04:28:40Z","timestamp":1773894520373,"version":"3.50.1"},"reference-count":86,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2021,3,26]],"date-time":"2021-03-26T00:00:00Z","timestamp":1616716800000},"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>2-(2-Fluoro-4-biphenyl) propionic acid (flurbiprofen), from the phenylalkanoic acid family of nonsteroidal anti-inflammatory drugs (NSAID\u2019s), is currently on the pharmaceutical market as a racemate. This racemic compound was tested for its propensity to undergo the self-disproportionation of enantiomers (SDE) phenomenon by various forms of chromatography (SDEvC), such as routine gravity-driven column chromatography, medium-pressure liquid chromatography (MPLC), preparative thin-layer chromatography (PTLC), and size-exclusion chromatography (SEC), as well as by sublimation (SDEvS). Furthermore, examination by nuclear magnetic resonance (NMR) in various solvents found that flurbiprofen exhibited the phenomenon of self-induced diastereomeric anisochronism (SIDA). By measurement of the diffusion coefficient (D), the longitudinal relaxation time (T1), and the transverse relaxation time (T2) using NMR, as well as by electrospray ionization-mass spectrometry (ESI-MS) examinations, the preferred intermolecular association was found to be solvent dependent, e.g., heterochiral association was preferred in toluene, while homochiral association was preferred in more polar solvents. This study also attempted, unsuccessfully, to correlate the NMR measurements of flurbiprofen with chromatographic outcomes for the rationalization and prediction of chromatographic results based on NMR measurements. Because the intermolecular hydrogen bonding of the acid groups in flurbiprofen overwhelmingly predominates over other intermolecular interactions, flurbiprofen seemed to represent a good test case for this idea. The behavior of scalemic samples of flurbiprofen is important, as, although it is currently dispensed as a racemate, clinical applications of the R enantiomer have been investigated. SDEvC and SDEvS both have ramifications for the preparation, handling, and storage of enantioenriched flurbiprofen, and this concern applies to other chiral drugs as well.<\/jats:p>","DOI":"10.3390\/sym13040543","type":"journal-article","created":{"date-parts":[[2021,3,26]],"date-time":"2021-03-26T06:59:42Z","timestamp":1616741982000},"page":"543","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Flurbiprofen: A Study of the Behavior of the Scalemate by Chromatography, Sublimation, and NMR"],"prefix":"10.3390","volume":"13","author":[{"given":"Magdalena","family":"Kwiatkowska","sequence":"first","affiliation":[{"name":"Institute of Chemistry, Jan Kochanowski University in Kielce, Uniwersytecka 7, 25-406 Kielce, Poland"}]},{"given":"Alicja","family":"Wzorek","sequence":"additional","affiliation":[{"name":"Institute of Chemistry, Jan Kochanowski University in Kielce, Uniwersytecka 7, 25-406 Kielce, Poland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3041-5368","authenticated-orcid":false,"given":"Anna","family":"Kolbus","sequence":"additional","affiliation":[{"name":"Institute of Chemistry, Jan Kochanowski University in Kielce, Uniwersytecka 7, 25-406 Kielce, Poland"}]},{"given":"Mariusz","family":"Urbaniak","sequence":"additional","affiliation":[{"name":"Institute of Chemistry, Jan Kochanowski University in Kielce, Uniwersytecka 7, 25-406 Kielce, Poland"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3817-0764","authenticated-orcid":false,"given":"Jianlin","family":"Han","sequence":"additional","affiliation":[{"name":"College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0681-4526","authenticated-orcid":false,"given":"Vadim A.","family":"Soloshonok","sequence":"additional","affiliation":[{"name":"Department of Organic Chemistry I, Faculty of Chemistry, University of the Basque Country UPV\/EHU, Paseo Manuel Lardiz\u00e1bal 3, E-20018 San Sebasti\u00e1n, Spain"},{"name":"IKERBASQUE, Basque Foundation for Science, Alameda Urquijo 36-5, Plaza Bizkaia, E-48011 Bilbao, Spain"}]},{"given":"Karel D.","family":"Klika","sequence":"additional","affiliation":[{"name":"Molecular Structure Analysis, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany"}]}],"member":"1968","published-online":{"date-parts":[[2021,3,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"180","DOI":"10.1016\/j.trac.2018.07.020","article-title":"Self-induced recognition of enantiomers (SIRE) and its application in chiral NMR analysis","volume":"109","author":"Lomoschitz","year":"2018","journal-title":"Trends Anal. 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