{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:43:33Z","timestamp":1760237013711,"version":"build-2065373602"},"reference-count":54,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2020,2,12]],"date-time":"2020-02-12T00:00:00Z","timestamp":1581465600000},"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":["SFRH\/BD\/136692\/2018","UID\/QUI\/50006\/2019","RECI\/BBB-BQB\/0230\/2012"],"award-info":[{"award-number":["SFRH\/BD\/136692\/2018","UID\/QUI\/50006\/2019","RECI\/BBB-BQB\/0230\/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>The synthesis of an unreported 2-aminopyrrolidine-1-carboxamidine unit is here described for the first time. This unusual and promising structure was attained through the oxidative decarboxylation of amino acids using the pair of reagents, silver(I)\/peroxydisulfate (Ag(I)\/S2O82\u2212) followed by intermolecular (in the case of l-proline derivative) and intramolecular trapping (in the case of acyl l-arginine) by N-nucleophiles. The l-proline approach has a broader scope for the synthesis of 2-aminopyrrolidine-1-carboxamidine derivatives, whereas the intramolecular cyclization afforded by the l-acylarginines, when applied, results in higher yields. The former allowed the first synthesis of cernumidine, a natural alkaloid isolated in 2011 from Solanum cernuum Vell, as its racemic form.<\/jats:p>","DOI":"10.3390\/molecules25040797","type":"journal-article","created":{"date-parts":[[2020,2,26]],"date-time":"2020-02-26T05:44:12Z","timestamp":1582695852000},"page":"797","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Synthetic Approaches to a Challenging and Unusual Structure\u2014An Amino-Pyrrolidine Guanine Core"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7235-0083","authenticated-orcid":false,"given":"Rafael","family":"Rippel","sequence":"first","affiliation":[{"name":"LAQV-REQUIMTE, NOVA School of Science and Technology, 2829-516 Caparica, Portugal"}]},{"given":"Lu\u00eds","family":"Pinheiro","sequence":"additional","affiliation":[{"name":"LAQV-REQUIMTE, NOVA School of Science and Technology, 2829-516 Caparica, Portugal"}]},{"given":"M\u00f3nica","family":"Lopes","sequence":"additional","affiliation":[{"name":"LAQV-REQUIMTE, NOVA School of Science and Technology, 2829-516 Caparica, Portugal"}]},{"given":"Ana","family":"Louren\u00e7o","sequence":"additional","affiliation":[{"name":"LAQV-REQUIMTE, NOVA School of Science and Technology, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8474-3925","authenticated-orcid":false,"given":"Lu\u00edsa M.","family":"Ferreira","sequence":"additional","affiliation":[{"name":"LAQV-REQUIMTE, NOVA School of Science and Technology, 2829-516 Caparica, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7312-8596","authenticated-orcid":false,"given":"Paula S.","family":"Branco","sequence":"additional","affiliation":[{"name":"LAQV-REQUIMTE, NOVA School of Science and Technology, 2829-516 Caparica, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2020,2,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1114","DOI":"10.1002\/anie.201105840","article-title":"Lead-oriented synthesis: A new opportunity for synthetic chemistry","volume":"51","author":"Nadin","year":"2012","journal-title":"Angew. 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