The coordination properties of 2-picolinehydroxamic acid towards cobalt(II) in aqueous solution were determined by a pH-metric method and confirmed by spectroscopic (UV–Vis and ESI-MS) studies. The results show the formation of mononuclear complexes, as well as of metallacrowns (MC). All methods indicate a high tendency of 2-picolinehydroxamic acid to form cobalt(II) metallacrown 12-MC-4. ESI-MS additionally confirms 15-MC-5 and 18-MC-6, stabilized by a sodium ion and methanol. The complexes observed in the speciation model at a pH about 7.2 were studied for their DNA-binding ability. The decrease of absorbance in the range of ca 310–400 nm indicates effective binding to calf thymus DNA by 2-picolinehydroxamic acid complexes, via intercalative mode. The antimicrobial properties of 2-picolinehydroxamic acid, cobalt(II) ions and of the complexes formed in the Co(II) – ligand system were determined against Gram-positive bacteria (Enterococcus faecalis, Enterococcus faecium, Staphylococcus aureus, Bacillus subtilis), Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Helicobacter pylori) and fungal strains (Candida, Aspergillus niger). The results indicate that the complexes demonstrate greater antibacterial and antifungal activity for most strains than the ligand. Both the complexes and the ligand induce a slight decrease in the metabolic activity of cells, while the complexes do not damage the cell nuclei. The 2-picolinehydroxamic acid complexes activate the human monocytic cells, suggesting they have immunomodulating properties, which are particularly important in combating infections caused by strains resistant to other drugs.

2-甲基吡啶氧肟酸对水溶液中钴（II）的配位性能通过pH值测定方法确定，并通过光谱法（UV-Vis和ESI-MS）进行了证实。结果表明，形成了单核络合物以及金属催乳激素（MC）。所有方法都表明2-甲基吡啶氧肟酸形成金属钴（II）钴12-MC-4的可能性很高。ESI-MS还确认了15-MC-5和18-MC-6，由钠离子和甲醇稳定。研究了在物种形成模型中观察到的复合物在pH约7.2时的DNA结合能力。吸光度是否在范围内的降低CA 310-400纳米表明了有效的通过2- picolinehydroxamic酸络合物结合的小牛胸腺DNA，通过插入模式。确定了2-甲基吡啶氧肟酸，钴（II）离子和在钴（II）-配体系统中形成的配合物对革兰氏阳性细菌（粪肠球菌，粪肠球菌，金黄色葡萄球菌，枯草芽孢杆菌），革兰氏杆菌的抗菌性能阴性菌（铜绿假单胞菌，大肠杆菌，幽门螺杆菌）和真菌菌株（念珠菌，黑曲霉）。结果表明，该复合物对大多数菌株显示出比配体更大的抗菌和抗真菌活性。复合物和配体都诱导细胞的代谢活性略有下降，而复合物不损害细胞核。2-picolinehydroxamic酸复合物激活人单核细胞，表明它们具有免疫调节特性，这在抵抗由对其他药物具有抗性的菌株引起的感染中尤为重要。