Scheme 1. Structures of the ligands.

Fig. 1. NMR spectra of the ligands and their complexes.

Fig. 2. Cytotoxic effects of the tested zirconium complex Z-1 against the human promyelocyte leukemia HL-60 after 72 h exposure as assessed by the MTT-dye reduction assay. Each data point represents the arithmetic mean ± standard deviation of at least six independent experiments.

Fig. 3. Cytotoxic effects of the tested zirconium complex Z-2 against the human promyelocyte leukemia HL-60 after 72 h exposure as assessed by the MTT-dye reduction assay. Each data point represents the arithmetic mean ± standard deviation of at least six independent experiments.

Fig. 4. Cytotoxic effects of the tested zirconium complex Z-3 against the human promyelocyte leukemia HL-60 after 72 h exposure as assessed by the MTT-dye reduction assay. Each data point represents the arithmetic mean ± standard deviation of at least six independent experiments.

Fig. 5. Cytotoxic effects of L₁ against the acute myeloid leukemia HL-60 after 72 h exposure as assessed by the MTT-dye reduction assay. Each data point represents the arithmetic mean ± standard deviation of at least four independent experiments.

Fig. 6. Cytotoxic effects of L₂ against the acute myeloid leukemia HL-60 after 72 h exposure as assessed by the MTT-dye reduction assay. Each data point represents the arithmetic mean ± standard deviation of at least four independent experiments.

Fig. 7. Cytotoxic effects of L₃ against the acute myeloid leukemia HL-60 after 72 h exposure as assessed by the MTT-dye reduction assay. Each data point represents the arithmetic mean ± standard deviation of at least four independent experiments.

Fig. 8. Cytotoxic effects of ZrCl₄ against the acute myeloid leukemia HL-60 after 72 h exposure as assessed by the MTT-dye reduction assay. Each data point represents the arithmetic mean ± standard deviation of at least four independent experiments.

Fig. 9. Cytotoxic effects of the tested zirconium complex Z-1 against the chronic myeloid leukemia LAMA-84 after 72 h exposure as assessed by the MTT-dye reduction assay. Each data point represents the arithmetic mean ± standard deviation of at least six independent experiments.

Fig. 10. Cytotoxic effects of the tested zirconium complex Z-2 against the chronic myeloid leukemia LAMA-84 after 72 h exposure as assessed by the MTT-dye reduction assay. Each data point represents the arithmetic mean ± standard deviation of at least six independent experiments.

Fig. 11. Cytotoxic effects of the tested zirconium complex Z-3 against the chronic myeloid leukemia LAMA-84 after 72 h exposure as assessed by the MTT-dye reduction assay. Each data point represents the arithmetic mean ± standard deviation of at least six independent experiments.

Fig. 12. Cytotoxic effects of L₁ against the chronic myeloid leukemia LAMA-84 after 72 h exposure as assessed by the MTT-dye reduction assay. Each data point represents the arithmetic mean ± standard deviation of at least four independent experiments.

Fig. 13. Cytotoxic effects of L₂ against the chronic myeloid leukemia LAMA-84 after 72 h exposure as assessed by the MTT-dye reduction assay. Each data point represents the arithmetic mean ± standard deviation of at least four independent experiments.

Fig. 14. Cytotoxic effects of L₂ against the chronic myeloid leukemia LAMA-84 after 72 h exposure as assessed by the MTT-dye reduction assay. Each data point represents the arithmetic mean ± standard deviation of at least four independent experiments.

Fig. 15. Cytotoxic effects of ZrCl₄ against the chronic myeloid leukemia LAMA-84 after 72 h exposure as assessed by the MTT-dye reduction assay. Each data point represents the arithmetic mean ± standard deviation of at least four independent experiments.

Elemental analysis data for Zr (IV) complexes with bis-coumarins

L₁: C₂₂H₁₂N₂O₆^2–; L₂: C₂₄H₁₃NO₆^2–; L₃: C₂₄H₁₃NO₆^2–.

Mass spectral data of bis-coumarins and their Zr (IV) complexes

Selected experimental IR frequencies of the ligands and their Zr (IV) complexes (cm⁻¹)

^a br: broad; s: strong; m-medium; sh: shoulder; w: weak.

¹H-NMR spectral shifts, δ (ppm) of the ligands and their Zr (IV) complexes (250 MHz, DMSO-d₆)

Spectrophotometrical data from the MTT assay concerning the cytotoxic effects of the newly synthesized zirconium complexes of bis(4-hydroxy-2-oxo-2H-chromen-3-yl)-(1H-pyrazol-3-yl)-methane (Z-1), bis(4-hydroxy-2-oxo-2H-chromen-3-yl)-piridin-3-yl-methane (Z-2) and bis(4-hydroxy-2-oxo-2H-chromen-3-yl)-piridin-4-yl-methane (Z-3) on HL-60 leukemic cells

Each value represents the arithmetic mean ± standard deviation of at least six independent experiments.

Spectrophotometrical data from the MTT assay concerning the cytotoxic effects of ZrC₄ and the bis-coumarin ligands bis(4-hydroxy-2-oxo-2H-chromen-3-yl)-(1H-pyrazol-3-yl)-methane (L₁) bis(4-hydroxy-2-oxo-2H-chromen-3-yl)-piridin-3-yl-methane (L₂) and bis(4-hydroxy-2-oxo-2H-chromen-3-yl)-piridin-4-yl-methane (L₃) on HL-60 leukemic cells

Each value represents the arithmetic mean ± standard deviation of at least six independent experiments.

Spectrophotometrical data from the MTT assay concerning the cytotoxic effects of the newly synthesized zirconium complexes of bis(4-hydroxy-2-oxo-2H-chromen-3-yl)-(1H-pyrazol-3-yl)-methane (Z-1), bis(4-hydroxy-2-oxo-2H-chromen-3-yl)-piridin-3-yl-methane (Z-2) and bis(4-hydroxy-2-oxo-2H-chromen-3-yl)-piridin-4-yl-methane (Z-3) on LAMA-84 leukemic cells

Each value represents the arithmetic mean ± standard deviation of at least six independent experiments.

Spectrophotometrical data from the MTT assay concerning the cytotoxic effects of ZrC₄ and the bis-coumarin ligands bis(4-hydroxy-2-oxo-2H-chromen-3-yl)-(1H-pyrazol-3-yl)-methane (L₁) bis(4-hydroxy-2-oxo-2H-chromen-3-yl)-piridin-3-yl-methane (L₂) and bis(4-hydroxy-2-oxo-2H-chromen-3-yl)-piridin-4-yl-methane (L₃) on LAMA-84 leukemic cells

Relative potency of the compounds after 72 h exposure (MTT-dye reduction assay)