Exploring zinc(II) coordination chemistry with picolinate and amino alcohols : toward new antibacterial agents

Modec, Barbara (author), Podjed Rihtaršič, Nina (author), López-Serrano, Joaquín (author), Hrast Rambaher, Martina (author), Golob, Majda (author)

Zinc(II) coordination chemistry with picolinate (abbreviated as pic$^–$, an anion of pyridine-2-carboxylic acid) and a series of β-amino alcohols (2-aminoethanol, 2-methylaminoethanol, 2-ethylaminoethanol, 2-dimethylaminoethanol, 2-amino-1-propanol, 1-amino-2-butanol, and 1-amino-2-methyl-2-propanol) was systematically investigated. Reaction systems typically yielded complexes with the general composition [Zn(pic)$_2$(amino alcohol)] via a straightforward synthetic route. Zinc(II) adopts an octahedral coordination environment consisting of two N,O-bidentate chelating picolinates and one amino alcohol, likewise coordinated in a chelating manner through amino and hydroxyl groups. As no fac isomers were isolated, the relative stability of mer and fac isomers of the 2-methylaminoethanol complex was evaluated by DFT calculations, which supported a preference for the mer geometry. Interestingly, the 1-amino-2-methyl-2-propanol system also produced an ionic species, [Zn(pic)$_3$]$^−$, which crystallized as a salt with protonated amino alcohol. All novel compounds were characterized using infrared and $^1$H NMR spectroscopy, elemental analysis, mass spectrometry, and single-crystal X-ray diffraction. Selected tris-chelates displayed moderate antibacterial activity against S. epidermidis, with MIC values ranging from 32 to 64 μg/mL, whereas picolinic acid alone was inactive.

• Language: English
• Keywords: zinc(II), picolinic acid, amino alcohols, crystal structure, DFT calculations, antibacterial activity
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FKKT - Faculty of Chemistry and Chemical Technology
• Publication status: Published
• Publication version: Version of Record
• Year: 2026
• Number of pages: Str. 32955-32970
• Numbering: Vol. 11, iss. 22
• PID: 20.500.12556/RUL-186510
• UDC: 546.47:547.435:547.82
• ISSN on article: 2470-1343
• DOI: 10.1021/acsomega.6c02474
• COBISS.SI-ID: 282035459
• Publication date in RUL: 02.09.2026

Record is a part of a journal

• Title: ACS omega
• Shortened title: ACS omega
• Publisher: American Chemical Society
• ISSN: 2470-1343
• COBISS.SI-ID: 525873945

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: cink(II), pikolinska kislina, amino alkoholi, kristalne strukture, DFT izračuni, protibakterijsko delovanje