{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,22]],"date-time":"2026-08-22T04:28:16Z","timestamp":1787372896189,"version":"build-2736575974"},"reference-count":40,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T00:00:00Z","timestamp":1787184000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"MUR","award":["CUP G53D23003280006"],"award-info":[{"award-number":["CUP G53D23003280006"]}]},{"name":"MUR","award":["CUP G53D23003260006"],"award-info":[{"award-number":["CUP G53D23003260006"]}]},{"name":"European Union\u2014NextGenerationEU"},{"id":[{"id":"https:\/\/ror.org\/019w4f821","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Novel and efficient total syntheses of the nonsteroidal anti-inflammatory drugs Pelubiprofen and Loxoprofen via a photo-Favorskii rearrangement are reported herein. The key photochemical transformation was optimized under both batch and continuous-flow conditions using a suitably functionalized chloro-phenylpropan-1-one derivative, affording the target 2-arylpropionic acid in excellent yield. Implementation under continuous-flow conditions increased process productivity and enabled gram-scale operation. Aerobic oxidation of the benzylic position to the corresponding aldehyde, followed by Claisen\u2013Schmidt condensation with cyclohexanone, afforded Pelubiprofen in 35% overall yield. Alternatively, condensation with cyclopentanone afforded the corresponding \u03b1,\u03b2-unsaturated enone intermediate, whose selective reduction under flow conditions enabled access to Loxoprofen in 28% overall yield. The versatility of the methodology was further demonstrated through the synthesis of Carprofen, highlighting the broader applicability of the photo-Favorskii rearrangement to the synthesis of APIs through previously unreported synthetic routes.<\/jats:p>","DOI":"10.3390\/molecules31162910","type":"journal-article","created":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T09:48:31Z","timestamp":1787219311000},"page":"2910","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Synthesis of Non-Steroidal Anti-Inflammatory Drugs Pelubiprofen, Loxoprofen, and Carprofen Through Batch and Continuous-Flow Photo-Favorskii Rearrangement"],"prefix":"10.3390","volume":"31","author":[{"ORCID":"https:\/\/orcid.org\/0009-0009-5056-1678","authenticated-orcid":false,"given":"Sara","family":"Ferrario","sequence":"first","affiliation":[{"name":"Dipartimento di Chimica, Universit\u00e0 degli Studi di Milano, Via C. Golgi 19, 20133 Milan, MI, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paolo","family":"Celestini","sequence":"additional","affiliation":[{"name":"Cosma S.p.A., Via B. Colleoni 15\u201317, 24040 Ciserano, BG, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gabriele","family":"Rebuzzini","sequence":"additional","affiliation":[{"name":"Cosma S.p.A., Via B. Colleoni 15\u201317, 24040 Ciserano, BG, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2694-9535","authenticated-orcid":false,"given":"Sergio","family":"Rossi","sequence":"additional","affiliation":[{"name":"Dipartimento di Chimica, Universit\u00e0 degli Studi di Milano, Via C. Golgi 19, 20133 Milan, MI, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9568-9642","authenticated-orcid":false,"given":"Maurizio","family":"Benaglia","sequence":"additional","affiliation":[{"name":"Dipartimento di Chimica, Universit\u00e0 degli Studi di Milano, Via C. Golgi 19, 20133 Milan, MI, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1716","DOI":"10.1056\/NEJM199106133242407","article-title":"Nonsteroidal antiinflammatory drugs\u2014Differences and similarities","volume":"324","author":"Brooks","year":"1991","journal-title":"N. Engl. J. 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