{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,30]],"date-time":"2026-03-30T07:20:32Z","timestamp":1774855232230,"version":"3.50.1"},"reference-count":63,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2025,7,25]],"date-time":"2025-07-25T00:00:00Z","timestamp":1753401600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Deanship of Scientific Research, Jordan University of Science and Technology","award":["20230403"],"award-info":[{"award-number":["20230403"]}]},{"name":"University of Business and Technology","award":["20230403"],"award-info":[{"award-number":["20230403"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Background: Transition metal complexes incorporating fluorinated counter anions represent a significant class of compounds with broad applications in industry, pharmaceuticals, and biomedicine. These fluorinated anions are known to enhance the solubility, stability, and reactivity of the complexes, thereby expanding their functional utility in various chemical and biological contexts. Methods: A set of metal(II) complexes of the general formula [MPy6][B(C6F5)4]2 where (Py = pyridine, M = Mn (1), Fe (2), Co (3), Ni (4), Cu (5), Zn (6)) have been synthesized by direct reaction of metal halides and pyridine in the presence of Ag[B(C6F5)4]. The complexes were characterized using different techniques to assure their purity, such as elemental analysis (EA), electron paramagnetic resonance (EPR) spectroscopy, thermogravimetric analysis (TGA), ultraviolet\u2013visible (UV\u2013Vis) spectroscopy, 11B-NMR, 1H-NMR, and FT-IR spectroscopy. The antimicrobial and antifungal properties against different types of bacteria and fungi were studied for all prepared complexes. Results: The synthesized complexes exhibited broad-spectrum antimicrobial activity, demonstrating variable efficacy compared to the reference antibiotic, oxytetracycline (positive control). Notably, complex 6 displayed exceptional antibacterial activity against Streptococcus pyogenes, with a minimum inhibitory concentration (MIC) of 4 \u00b5g\/mL, outperforming the control (MIC = 8 \u00b5g\/mL). Complexes 1, 2, and 4 showed promising activity against Shigella flexneri, Klebsiella pneumoniae, and Streptococcus pyogenes, each with MIC values of 8 \u00b5g\/mL. Conversely, the lowest activity (MIC = 512 \u00b5g\/mL) was observed for complexes 3, 5, and 6 against Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae, respectively. Regarding antifungal properties, complexes 5 and 6 demonstrated the highest activity against Candida albicans, with MIC values of 8 \u00b5g\/mL, equivalent to that of the positive control, fluconazole. Density functional theory (DFT) calculations confirmed an overall octahedral coordination geometry for all complexes, with tetragonal distortions identified in complexes 3, 4, and 5.<\/jats:p>","DOI":"10.3390\/molecules30153121","type":"journal-article","created":{"date-parts":[[2025,7,25]],"date-time":"2025-07-25T11:38:41Z","timestamp":1753443521000},"page":"3121","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Anti-Bacterial and Anti-Fungal Properties of a Set of Transition Metal Complexes Bearing a Pyridine Moiety and [B(C6F5)4]2 as a Counter Anion"],"prefix":"10.3390","volume":"30","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1005-3160","authenticated-orcid":false,"given":"Ahmed K.","family":"Hijazi","sequence":"first","affiliation":[{"name":"Department of Chemistry, College of Arts and Sciences, University of Petra, P.O. Box 961343, Amman 11196, Jordan"},{"name":"Department of Chemical Sciences, Faculty of Science and Arts, Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5201-2287","authenticated-orcid":false,"given":"Mohammad","family":"El-Khateeb","sequence":"additional","affiliation":[{"name":"Department of Chemical Sciences, Faculty of Science and Arts, Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7675-9326","authenticated-orcid":false,"given":"Ziyad A.","family":"Taha","sequence":"additional","affiliation":[{"name":"Department of Chemical Sciences, Faculty of Science and Arts, Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7015-0691","authenticated-orcid":false,"given":"Mohammed I.","family":"Alomari","sequence":"additional","affiliation":[{"name":"Department of Chemistry, College of Arts and Sciences, University of Petra, P.O. Box 961343, Amman 11196, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Noor M.","family":"Khwaileh","sequence":"additional","affiliation":[{"name":"Department of Chemical Sciences, Faculty of Science and Arts, Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Abbas I.","family":"Alakhras","sequence":"additional","affiliation":[{"name":"Department of Chemistry, College of Science, Imam Mohammad Ibn Saud Islamic University, P.O. Box 5701, Riyadh 11432, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8952-7295","authenticated-orcid":false,"given":"Waleed M.","family":"Al-Momani","sequence":"additional","affiliation":[{"name":"Department of Basic Medical Sciences, Faculty of Medicine, Yarmouk University, Irbid 21163, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ali","family":"Elrashidi","sequence":"additional","affiliation":[{"name":"Electrical Engineering Department, College of Engineering, University of Business and Technology, Jeddah 23435, Saudi Arabia"},{"name":"Engineering Mathematics Department, Faculty of Engineering, Alexandria University, Alexandria 21544, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ahmad S.","family":"Barham","sequence":"additional","affiliation":[{"name":"Department of Chemistry, School of Science, The University of Jordan, Amman 11942, Jordan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"134","DOI":"10.1016\/S0020-1693(98)00383-1","article-title":"Synthesis, structural characterization and biological activity of helicin thiosemicarbazone monohydrate and a copper(II) complex of salicylaldehyde thiosemicarbazone","volume":"286","author":"Ferrari","year":"1999","journal-title":"Inorg. 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