{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,14]],"date-time":"2025-10-14T11:34:43Z","timestamp":1760441683630,"version":"build-2065373602"},"reference-count":30,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2021,9,4]],"date-time":"2021-09-04T00:00:00Z","timestamp":1630713600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/04612\/2020","UIDP\/04612\/2020","IF\/00109\/2014\/CP1244\/CT0007","PD\/BD\/135483\/2018","SFRH\/BD\/1444412019","UIDB\/50006\/2020, UIDP\/50006\/2020, UIDB\/04378\/2020, UIDP\/04378\/2020","RECI\/BBB-BEP\/0124\/2012"],"award-info":[{"award-number":["UIDB\/04612\/2020","UIDP\/04612\/2020","IF\/00109\/2014\/CP1244\/CT0007","PD\/BD\/135483\/2018","SFRH\/BD\/1444412019","UIDB\/50006\/2020, UIDP\/50006\/2020, UIDB\/04378\/2020, UIDP\/04378\/2020","RECI\/BBB-BEP\/0124\/2012"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Organometallic derivatization of nucleosides is a highly promising strategy for the improvement of the therapeutic profile of nucleosides. Herein, a methodology for the synthesis of metalated adenosine with a deprotected ribose moiety is described. Platinum(II) N-heterocyclic carbene complexes based on adenosine were synthesized, namely N-heterocyclic carbenes bearing a protected and unprotected ribose ring. Reaction of the 8-bromo-2\u2032,3\u2032,5\u2032-tri-O-acetyladenosine with Pt(PPh3)4 by C8\u2212Br oxidative addition yielded complex 1, with a PtII centre bonded to C-8 and an unprotonated N7. Complex 1 reacted at N7 with HBF4 or methyl iodide, yielding protic carbene 2 or methyl carbene 3, respectively. Deprotection of 1 to yield 4 was achieved with NH4OH. Deprotected compound 4 reacted at N7 with HCl solutions to yield protic NHC 5 or with methyl iodide yielding methyl carbene 6. Protic N-heterocyclic carbene 5 is not stable in DMSO solutions leading to the formation of compound 7, in which a bromide was replaced by chloride. The cis-influence of complexes 1\u20137 was examined by 31P{1H} and 195Pt NMR. Complexes 2, 3, 5, 6 and 7 induce a decrease of 1JPt,P of more than 300 Hz, as result of the higher cis-influence of the N-heterocyclic carbene when compared to the azolato ligand in 1 and 4.<\/jats:p>","DOI":"10.3390\/molecules26175384","type":"journal-article","created":{"date-parts":[[2021,9,6]],"date-time":"2021-09-06T13:18:26Z","timestamp":1630934306000},"page":"5384","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Synthesis of Platinum(II) N-Heterocyclic Carbenes Based on Adenosine"],"prefix":"10.3390","volume":"26","author":[{"given":"Maria In\u00eas P. S.","family":"Leit\u00e3o","sequence":"first","affiliation":[{"name":"ITQB-NOVA\u2014Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Universidade Nova de Lisboa, Avd da Republica, 2780-157 Oeiras, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9199-130X","authenticated-orcid":false,"given":"Giulia","family":"Francescato","sequence":"additional","affiliation":[{"name":"ITQB-NOVA\u2014Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Universidade Nova de Lisboa, Avd da Republica, 2780-157 Oeiras, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3672-0045","authenticated-orcid":false,"given":"Clara S. B.","family":"Gomes","sequence":"additional","affiliation":[{"name":"LAQV-REQUIMTE, Department of Chemistry, NOVA School of Science and Technology, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal"},{"name":"Associate Laboratory i4 HB\u2014Institute for Health and Bioeconomy, School of Science and Technology, NOVA University Lisbon, 2819\u2013516 Caparica, Portugal"},{"name":"UCIBIO\u2014Applied Molecular Biosciences Unit, Department of Chemistry, School of Science and Technology, NOVA University Lisbon, 2819-516 Caparica, Portugal"}]},{"given":"Ana","family":"Petronilho","sequence":"additional","affiliation":[{"name":"ITQB-NOVA\u2014Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Universidade Nova de Lisboa, Avd da Republica, 2780-157 Oeiras, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8802","DOI":"10.1039\/C5CS00486A","article-title":"Ferrocifen Type Anti Cancer Drugs","volume":"44","author":"Top","year":"2015","journal-title":"Chem. 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