Mg(II) and Ca(II) complexes with cefazolin were synthesized and investigated using elemental and atomic-emission analysis, TGA, X-ray diffraction, FT-IR spectroscopy, ¹H and ¹³CNMR, DFT calculations, and QTAIM analysis. The thermal behavior of these complexes was also studied. In the magnesium complex, two cefazolin ions are coordinated to the metal ion through the oxygen atoms of the lactam and carboxylate groups as a bidentate ligand. However, cefazolin chelated to the calcium ion through both oxygen atoms of the carboxylate groups and the lactam groups′ oxygen atoms as tridentate ligand. Sodium cefazolin and metal complexes were also screened for antibacterial activity against Staphylococcus aureus and Escherichia coli. The calcium complex exhibited higher antibacterial effects than the magnesium complex (5.2–7.7 % higher against S. aureus– and 15.4–27.3 % against E. coli), which is related to weaker binding of Ca, compared to Mg, with the oxygen atom of lactam group and, as a result, more free releasing of the lactam group in the solving process.

中文翻译：

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头孢唑啉与 Ca2+ 和 Mg2+ 的复合物形成：合成、DFT、光谱和抗菌测定

使用元素和原子发射分析、TGA、X 射线衍射、FT-IR 光谱、¹ H 和¹³ CNMR、DFT 计算和 QTAIM 分析合成和研究了 Mg(II) 和 Ca(II) 与头孢唑啉的配合物。还研究了这些配合物的热行为。在镁络合物中，两个头孢唑啉离子通过内酰胺和羧酸根基团的氧原子作为双齿配体与金属离子配位。然而，头孢唑啉通过羧酸根的氧原子和内酰胺基的氧原子作为三齿配体与钙离子螯合。还筛选了头孢唑啉钠和金属配合物对金黄色葡萄球菌和大肠杆菌的抗菌活性. 钙复合物表现出比镁复合物更高的抗菌作用（对金黄色葡萄球菌高5.2-7.7%，对大肠杆菌高15.4-27.3% ），这与钙与氧原子的结合较镁弱有关内酰胺基团，因此在溶解过程中更多的内酰胺基团自由释放。