{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,4]],"date-time":"2026-08-04T10:56:10Z","timestamp":1785840970895,"version":"3.56.0"},"reference-count":44,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2019,12,19]],"date-time":"2019-12-19T00:00:00Z","timestamp":1576713600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001824","name":"Grantov\u00e1 Agentura \u010cesk\u00e9 Republiky","doi-asserted-by":"publisher","award":["17-27514Y"],"award-info":[{"award-number":["17-27514Y"]}],"id":[{"id":"10.13039\/501100001824","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100008530","name":"European Regional Development Fund","doi-asserted-by":"publisher","award":["CZ.02.1.01\/0.0\/0.0\/16_019\/0000841"],"award-info":[{"award-number":["CZ.02.1.01\/0.0\/0.0\/16_019\/0000841"]}],"id":[{"id":"10.13039\/501100008530","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Biomolecules"],"abstract":"<jats:p>4-aminobenzoic acid (PABA), an essential nutrient for many human pathogens, but dispensable for humans, and its derivatives have exhibited various biological activities. In this study, we combined two pharmacophores using a molecular hybridization approach: this vitamin-like molecule and various aromatic aldehydes, including salicylaldehydes and 5-nitrofurfural, via imine bond in one-step reaction. Resulting Schiff bases were screened as potential antimicrobial and cytotoxic agents. The simple chemical modification of non-toxic PABA resulted in constitution of antibacterial activity including inhibition of methicillin-resistant Staphylococcus aureus (minimum inhibitory concentrations, MIC, from 15.62 \u00b5M), moderate antimycobacterial activity (MIC \u2265 62.5 \u00b5M) and potent broad-spectrum antifungal properties (MIC of \u2265 7.81 \u00b5M). Some of the Schiff bases also exhibited notable cytotoxicity for cancer HepG2 cell line (IC50 \u2265 15.0 \u00b5M). Regarding aldehyde used for the derivatization of PABA, it is possible to tune up the particular activities and obtain derivatives with promising bioactivities.<\/jats:p>","DOI":"10.3390\/biom10010009","type":"journal-article","created":{"date-parts":[[2019,12,23]],"date-time":"2019-12-23T03:15:01Z","timestamp":1577070901000},"page":"9","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":70,"title":["4-Aminobenzoic Acid Derivatives: Converting Folate Precursor to Antimicrobial and Cytotoxic Agents"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4600-8409","authenticated-orcid":false,"given":"Martin","family":"Kr\u00e1tk\u00fd","sequence":"first","affiliation":[{"name":"Department of Organic and Bioorganic Chemistry, Faculty of Pharmacy in Hradec Kr\u00e1lov\u00e9, Charles University, Akademika Heyrovsk\u00e9ho 1203, 500 05 Hradec Kr\u00e1lov\u00e9, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5670-7767","authenticated-orcid":false,"given":"Kl\u00e1ra","family":"Kone\u010dn\u00e1","sequence":"additional","affiliation":[{"name":"Department of Biological and Medical Sciences, Faculty of Pharmacy in Hradec Kr\u00e1lov\u00e9, Charles University, Akademika Heyrovsk\u00e9ho 1203, 500 05 Hradec Kr\u00e1lov\u00e9, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3336-3874","authenticated-orcid":false,"given":"Ji\u0159\u00ed","family":"Janou\u0161ek","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Kr\u00e1lov\u00e9, Charles University, Akademika Heyrovsk\u00e9ho 1203, 500 05 Hradec Kr\u00e1lov\u00e9, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michaela","family":"Brabl\u00edkov\u00e1","sequence":"additional","affiliation":[{"name":"Unipetrol Centre of Research and Education, 436 70 Litv\u00ednov-Z\u00e1lu\u017e\u00ed 1, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4633-2062","authenticated-orcid":false,"given":"Ond\u0159ej","family":"Jan\u010fourek","sequence":"additional","affiliation":[{"name":"Department of Biological and Medical Sciences, Faculty of Pharmacy in Hradec Kr\u00e1lov\u00e9, Charles University, Akademika Heyrovsk\u00e9ho 1203, 500 05 Hradec Kr\u00e1lov\u00e9, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Franti\u0161ek","family":"Trejtnar","sequence":"additional","affiliation":[{"name":"Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec Kr\u00e1lov\u00e9, Charles University, Akademika Heyrovsk\u00e9ho 1203, 500 05 Hradec Kr\u00e1lov\u00e9, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ji\u0159ina","family":"Stola\u0159\u00edkov\u00e1","sequence":"additional","affiliation":[{"name":"Laboratory for Mycobacterial Diagnostics and Tuberculosis, Regional Institute of Public Health in Ostrava, Partyz\u00e1nsk\u00e9 n\u00e1m\u0115st\u00ed 7, 702 00 Ostrava, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jarmila","family":"Vin\u0161ov\u00e1","sequence":"additional","affiliation":[{"name":"Department of Organic and Bioorganic Chemistry, Faculty of Pharmacy in Hradec Kr\u00e1lov\u00e9, Charles University, Akademika Heyrovsk\u00e9ho 1203, 500 05 Hradec Kr\u00e1lov\u00e9, Czech Republic"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,12,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"562","DOI":"10.1016\/j.molstruc.2019.02.074","article-title":"Quinoxaline-PABA bipartite hybrid derivatization approach: Design and search for antimicrobial agents","volume":"1184","author":"Patel","year":"2019","journal-title":"J. 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