{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T20:59:33Z","timestamp":1791925173741,"version":"4.3.4"},"reference-count":31,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2014,11,18]],"date-time":"2014-11-18T00:00:00Z","timestamp":1416268800000},"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>Here we describe two novel uronium salts, TOMBU and COMBU, derived from the recently described Oxyma-B for use in peptide bond synthesis. These coupling reagents are more stable than COMU in DMF. Furthermore, using various peptide synthetic models in solution and solid-phase synthesis, we reveal that they show better performance than HBTU in terms of preserving chiral integrity and coupling yields, but slightly worse performance than COMU.<\/jats:p>","DOI":"10.3390\/molecules191118953","type":"journal-article","created":{"date-parts":[[2014,11,18]],"date-time":"2014-11-18T11:39:36Z","timestamp":1416310776000},"page":"18953-18965","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["TOMBU and COMBU as Novel Uronium-Type Peptide Coupling Reagents Derived from Oxyma-B"],"prefix":"10.3390","volume":"19","author":[{"given":"Yahya","family":"Jad","sequence":"first","affiliation":[{"name":"Catalysis and Peptide Research Unit, School of Health Sciences, University of Kwazulu-Natal, Durban 4001, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sherine","family":"Khattab","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Faculty of Science, Alexandria University, P.O. Box 426,  Ibrahimia, Alexandria 21321, Egypt"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Beatriz","family":"De la Torre","sequence":"additional","affiliation":[{"name":"Catalysis and Peptide Research Unit, School of Health Sciences, University of Kwazulu-Natal, Durban 4001, South Africa"},{"name":"School of Chemistry, Yachay Tech, Yachay City of Knowledge, 100119-Urcuqui, Ecuador"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Thavendran","family":"Govender","sequence":"additional","affiliation":[{"name":"Catalysis and Peptide Research Unit, School of Health Sciences, University of Kwazulu-Natal, Durban 4001, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0606-2053","authenticated-orcid":false,"given":"Hendrik","family":"Kruger","sequence":"additional","affiliation":[{"name":"Catalysis and Peptide Research Unit, School of Health Sciences, University of Kwazulu-Natal, Durban 4001, South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ayman","family":"El-Faham","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Faculty of Science, Alexandria University, P.O. Box 426,  Ibrahimia, Alexandria 21321, Egypt"},{"name":"Department of Chemistry, College of Science, King Saud University, P.O. Box 2455,  Riyadh 11451, Saudi Arabia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fernando","family":"Albericio","sequence":"additional","affiliation":[{"name":"Catalysis and Peptide Research Unit, School of Health Sciences, University of Kwazulu-Natal, Durban 4001, South Africa"},{"name":"School of Chemistry, Yachay Tech, Yachay City of Knowledge, 100119-Urcuqui, Ecuador"},{"name":"Department of Chemistry, College of Science, King Saud University, P.O. Box 2455,  Riyadh 11451, Saudi Arabia"},{"name":"School of Chemistry and Physics, University of KwaZulu-Natal, Durban 4001, South Africa"},{"name":"Institute for Research in Biomedicine (IRB Barcelona), Baldiri Reixac 10, Barcelona, 08028, Spain"},{"name":"CIBER-BBN, Networking Centre on Bioengineering, Biomaterials and Nanomedicine,  Barcelona Science Park, Barcelona 08028, Spain"},{"name":"Department of Organic Chemistry, University of Barcelona, Barcelona, 08028, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2014,11,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"104","DOI":"10.1016\/S0076-6879(97)89046-5","article-title":"Coupling reagents and activation","volume":"Volume 289","author":"Gregg","year":"1997","journal-title":"Methods Enzymol"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2243","DOI":"10.1021\/cr950005s","article-title":"Chemical synthesis of natural product peptides: Coupling methods for the incorporation of noncoded amino acids into peptides","volume":"97","author":"Humphrey","year":"1997","journal-title":"Chem. 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