{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,16]],"date-time":"2026-02-16T09:24:44Z","timestamp":1771233884642,"version":"3.50.1"},"reference-count":46,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2022,6,30]],"date-time":"2022-06-30T00:00:00Z","timestamp":1656547200000},"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>The suppression of side reactions is one of the most important objectives in peptide synthesis, where highly reactive compounds are involved. Recently, the violuric acid derivative Oxyma-B was introduced into peptide synthesis protocols as a promising additive to efficiently control the optical purity of the amino acids prone to racemization. However, we discovered a side reaction involving the Beckmann rearrangement of Oxyma-B during the coupling reaction, which compromises the yield and purity of the target peptides. Here, we present the investigation of the mechanism of this rearrangement and the optimization of the coupling reaction conditions to control it. These results can be taken into account for the design of novel efficient oxime-based coupling reagents.<\/jats:p>","DOI":"10.3390\/molecules27134235","type":"journal-article","created":{"date-parts":[[2022,7,1]],"date-time":"2022-07-01T00:21:50Z","timestamp":1656634910000},"page":"4235","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Carbodiimide-Mediated Beckmann Rearrangement of Oxyma-B as a Side Reaction in Peptide Synthesis"],"prefix":"10.3390","volume":"27","author":[{"given":"Andrea","family":"Orlandin","sequence":"first","affiliation":[{"name":"Fresenius Kabi iPSUM Srl, Via San Leonardo 23, 45010 Villadose, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6897-3528","authenticated-orcid":false,"given":"Ivan","family":"Guryanov","sequence":"additional","affiliation":[{"name":"Fresenius Kabi iPSUM Srl, Via San Leonardo 23, 45010 Villadose, Italy"},{"name":"Institute of Chemistry, St. Petersburg State University, Peterhof, Universitetskij pr. 26, 198504 St. Petersburg, Russia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lucia","family":"Ferrazzano","sequence":"additional","affiliation":[{"name":"Department of Chemistry \u201cGiacomo Ciamician\u201d, University of Bologna, Via Selmi 2, 40126 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2393-7333","authenticated-orcid":false,"given":"Barbara","family":"Biondi","sequence":"additional","affiliation":[{"name":"ICB, Padova Unit, CNR, Department of Chemistry, University of Padova, Via Marzolo 1, 35131 Padova, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Francesca","family":"Biscaglia","sequence":"additional","affiliation":[{"name":"ICB, Padova Unit, CNR, Department of Chemistry, University of Padova, Via Marzolo 1, 35131 Padova, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Claudia","family":"Storti","sequence":"additional","affiliation":[{"name":"ICB, Padova Unit, CNR, Department of Chemistry, University of Padova, Via Marzolo 1, 35131 Padova, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9967-5283","authenticated-orcid":false,"given":"Marzio","family":"Rancan","sequence":"additional","affiliation":[{"name":"ICMATE, CNR, Department of Chemistry, University of Padova, Via Marzolo 1, 35131 Padova, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fernando","family":"Formaggio","sequence":"additional","affiliation":[{"name":"ICB, Padova Unit, CNR, Department of Chemistry, University of Padova, Via Marzolo 1, 35131 Padova, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Antonio","family":"Ricci","sequence":"additional","affiliation":[{"name":"Fresenius Kabi iPSUM Srl, Via San Leonardo 23, 45010 Villadose, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7865-0474","authenticated-orcid":false,"given":"Walter","family":"Cabri","sequence":"additional","affiliation":[{"name":"Fresenius Kabi iPSUM Srl, Via San Leonardo 23, 45010 Villadose, Italy"},{"name":"Department of Chemistry \u201cGiacomo Ciamician\u201d, University of Bologna, Via Selmi 2, 40126 Bologna, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,6,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Srivastava, V. 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