{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,7]],"date-time":"2026-07-07T07:42:03Z","timestamp":1783410123238,"version":"3.54.6"},"reference-count":21,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2021,2,24]],"date-time":"2021-02-24T00:00:00Z","timestamp":1614124800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"CNPq\/FAPERGS\/CAPES\/BNDES","award":["421703-2017-2\/17-1265-8\/14.2.0914.1"],"award-info":[{"award-number":["421703-2017-2\/17-1265-8\/14.2.0914.1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Tuberculosis (TB) has been described as a global health crisis since the second half of the 1990s. Mycobacterium tuberculosis (Mtb), the etiologic agent of TB in humans, is a very successful pathogen, being the main cause of death in the population among infectious agents. In 2019, it was estimated that around 10 million individuals were contaminated by this bacillus and about 1.2 million succumbed to the disease. In recent years, our research group has reported the design and synthesis of quinoline derivatives as drug candidates for the treatment of TB. These compounds have demonstrated potent and selective growth inhibition of drug-susceptible and drug-resistant Mtb strains. Herein, a new synthetic approach was established providing efficient and rapid access (15 min) to a series of 4-alkoxy-6-methoxy-2-methylquinolines using ultrasound energy. The new synthetic protocol provides a simple procedure utilizing an open vessel system that affords the target products at satisfactory yields (45\u201384%) and elevated purities (\u226595%). The methodology allows the evaluation of a larger number of molecules in assays against the bacillus, facilitating the determination of the structure\u2013activity relationship with a reduced environmental cost.<\/jats:p>","DOI":"10.3390\/molecules26051215","type":"journal-article","created":{"date-parts":[[2021,2,25]],"date-time":"2021-02-25T02:36:13Z","timestamp":1614220573000},"page":"1215","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Ultrasound-Assisted Synthesis of 4-Alkoxy-2-methylquinolines: An Efficient Method toward Antitubercular Drug Candidates"],"prefix":"10.3390","volume":"26","author":[{"given":"Ana Fl\u00e1via","family":"Borsoi","sequence":"first","affiliation":[{"name":"Centro de Pesquisas em Biologia Molecular e Funcional, Instituto Nacional de Ci\u00eancia e Tecnologia em Tuberculose, Pontif\u00edcia Universidade Cat\u00f3lica do Rio Grande do Sul, 90616-900 Porto Alegre, Rio Grande do Sul, Brazil"},{"name":"Programa de P\u00f3s-Gradua\u00e7\u00e3o em Medicina e Ci\u00eancias da Sa\u00fade, Pontif\u00edcia Universidade Cat\u00f3lica do Rio Grande do Sul, 90616-900 Porto Alegre, Rio Grande do Sul, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Josiane Delgado","family":"Paz","sequence":"additional","affiliation":[{"name":"Centro de Pesquisas em Biologia Molecular e Funcional, Instituto Nacional de Ci\u00eancia e Tecnologia em Tuberculose, Pontif\u00edcia Universidade Cat\u00f3lica do Rio Grande do Sul, 90616-900 Porto Alegre, Rio Grande do Sul, Brazil"},{"name":"Programa de P\u00f3s-Gradua\u00e7\u00e3o em Biologia Celular e Molecular, Pontif\u00edcia Universidade Cat\u00f3lica do Rio Grande do Sul, 90616-900 Porto Alegre, Rio Grande do Sul, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kenia","family":"Pissinate","sequence":"additional","affiliation":[{"name":"Centro de Pesquisas em Biologia Molecular e Funcional, Instituto Nacional de Ci\u00eancia e Tecnologia em Tuberculose, Pontif\u00edcia Universidade Cat\u00f3lica do Rio Grande do Sul, 90616-900 Porto Alegre, Rio Grande do Sul, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5335-2654","authenticated-orcid":false,"given":"Raon\u00ed Scheibler","family":"Rambo","sequence":"additional","affiliation":[{"name":"Centro de Pesquisas em Biologia Molecular e Funcional, Instituto Nacional de Ci\u00eancia e Tecnologia em Tuberculose, Pontif\u00edcia Universidade Cat\u00f3lica do Rio Grande do Sul, 90616-900 Porto Alegre, Rio Grande do Sul, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"V\u00edctor Zajaczkowski","family":"Pestana","sequence":"additional","affiliation":[{"name":"Centro de Pesquisas em Biologia Molecular e Funcional, Instituto Nacional de Ci\u00eancia e Tecnologia em Tuberculose, Pontif\u00edcia Universidade Cat\u00f3lica do Rio Grande do Sul, 90616-900 Porto Alegre, Rio Grande do Sul, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cristiano Valim","family":"Bizarro","sequence":"additional","affiliation":[{"name":"Centro de Pesquisas em Biologia Molecular e Funcional, Instituto Nacional de Ci\u00eancia e Tecnologia em Tuberculose, Pontif\u00edcia Universidade Cat\u00f3lica do Rio Grande do Sul, 90616-900 Porto Alegre, Rio Grande do Sul, Brazil"},{"name":"Programa de P\u00f3s-Gradua\u00e7\u00e3o em Biologia Celular e Molecular, Pontif\u00edcia Universidade Cat\u00f3lica do Rio Grande do Sul, 90616-900 Porto Alegre, Rio Grande do Sul, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luiz Augusto","family":"Basso","sequence":"additional","affiliation":[{"name":"Centro de Pesquisas em Biologia Molecular e Funcional, Instituto Nacional de Ci\u00eancia e Tecnologia em Tuberculose, Pontif\u00edcia Universidade Cat\u00f3lica do Rio Grande do Sul, 90616-900 Porto Alegre, Rio Grande do Sul, Brazil"},{"name":"Programa de P\u00f3s-Gradua\u00e7\u00e3o em Medicina e Ci\u00eancias da Sa\u00fade, Pontif\u00edcia Universidade Cat\u00f3lica do Rio Grande do Sul, 90616-900 Porto Alegre, Rio Grande do Sul, Brazil"},{"name":"Programa de P\u00f3s-Gradua\u00e7\u00e3o em Biologia Celular e Molecular, Pontif\u00edcia Universidade Cat\u00f3lica do Rio Grande do Sul, 90616-900 Porto Alegre, Rio Grande do Sul, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pablo","family":"Machado","sequence":"additional","affiliation":[{"name":"Centro de Pesquisas em Biologia Molecular e Funcional, Instituto Nacional de Ci\u00eancia e Tecnologia em Tuberculose, Pontif\u00edcia Universidade Cat\u00f3lica do Rio Grande do Sul, 90616-900 Porto Alegre, Rio Grande do Sul, Brazil"},{"name":"Programa de P\u00f3s-Gradua\u00e7\u00e3o em Medicina e Ci\u00eancias da Sa\u00fade, Pontif\u00edcia Universidade Cat\u00f3lica do Rio Grande do Sul, 90616-900 Porto Alegre, Rio Grande do Sul, Brazil"},{"name":"Programa de P\u00f3s-Gradua\u00e7\u00e3o em Biologia Celular e Molecular, Pontif\u00edcia Universidade Cat\u00f3lica do Rio Grande do Sul, 90616-900 Porto Alegre, Rio Grande do Sul, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,24]]},"reference":[{"key":"ref_1","unstructured":"WHO (2021, January 19). 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