Synthesis, characterization and crystal structure of a diketone based Cu(II) complex and its catalytic activity for the synthesis of 1,2,3-triazoles

Synthesis and Investigations of the Antitumor Effects of First-Row Transition Metal(II) Complexes Supported by Two Fluorinated and Non-Fluorinated β-Diketonates

The 3d transition metal (Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II)) complexes, supported by anions of sterically demanding β-diketones, 1,3-dimesitylpropane-1,3-dione (HLMes) and 1,3-bis(3,5-bis(trifluoromethyl)phenyl)-3-hydroxyprop-2-en-1-one (HLCF3), were synthesized and evaluated for their antitumor activity. To assess the biological effects of substituents on phenyl moieties, we also synthesized and investigated the analogous metal(II) complexes of the anion of the less bulky 1,3-diphenylpropane-1,3-dione (HLPh) ligand. The compounds [Cu(LCF3)2], [Cu(LMes)2] and ([Zn(LMes)2]) were characterized by X-ray crystallography. The [Cu(LCF3)2] crystallizes with an apical molecule of solvent (THF) and features a rare square pyramidal geometry at the Cu(II) center. The copper(II) and zinc(II) complexes of diketonate ligands, derived from the deprotonated 1,3-dimesitylpropane-1,3-dione (HLMes), adopt a square planar or a tetrahedral geometry at the metal, respectively. We evaluated the antitumor properties of the newly synthesized (Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II)) complexes against a series of human tumor cell lines derived from different solid tumors. Except for iron derivatives, cellular studies revealed noteworthy antitumor properties, even towards cancer cells endowed with poor sensitivity to the reference drug cisplatin.

Supramolecular association of M2+⋯π induced by different electrostatic properties using naphthyl substituted β-diketonate complexes (metal = Cu, Pd, Pt)

Expanded π-conjugated coordination complexes, [M(L²)₂] (M = Cu²⁺, Pd²⁺, Pt²⁺; L² = dinaphthoylmethanido⁻), were prepared and their unique electron contributions and electrophile/nucleophile characteristics were found due to the supramolecular associations.

Arylhydrazone ligands as Cu-protectors and -catalysis promoters in the azide-alkyne cycloaddition reaction

A series of water soluble copper(ii) complexes, [Cu(κO¹O²N-H₂L¹)(H₂O)₂]·2H₂O (2), [Cu(κO-H₃L¹)₂(H₂O)₄] (3), [Cu(κO-H₄L²)₂(H₂O)₄] (5) and [Cu(H₂O)₆]·2H₂L³·2(CH₃)₂NCHO (7), were prepared by the reaction of Cu(NO₃)₂·3H₂O with sodium (Z)-2-(2-(1-amino-1,3-dioxobutan-2-ylidene)hydrazineyl)benzenesulfonate, [Na(μ₄-1:2κO¹,2κO²,3κO³,4κO⁴-H₃L¹)]_n (1; for 2 and 3), sodium (Z)-3-(2-(1-amino-1,3-dioxobutan-2-ylidene)hydrazineyl)-4-hydroxybenzene-sulfonate, [Na(μ-1κO¹,2κO²-H₄L²)]₂ (4; for 5) or sodium (Z)-2-(2-(1,3-dioxo-1-(phenylamino)butan-2-ylidene)hydrazineyl)naphthalene-1-sulfonate, [Na(μ-1κO¹O²,2κO³-H₂L³)(CH₃OH)₂]₂ (6; for 7). Compounds 1-7 were fully characterized, also by single-crystal X-ray diffraction analysis, and applied as homogeneous catalysts for the azide-alkyne cycloaddition (AAC) reaction to afford 1,4-disubstituted 1,2,3-triazoles. A structure-catalytic activity relationship has been recognized for the first time on the basis of the occurrence of resonance- and charge-assisted hydrogen bond interactions (RAHB and CAHB), in charge and ligand binding modes, enabling the catalytic activity of the compounds to be ordered as follows: Cu(NO₃)₂≪7 (complex salt with RAHB and CAHB) < 3 (with RAHB and CAHB) < 5 (with RAHB) < 2 (neither RAHB nor CAHB). Complex 2, without such non-covalent interactions, was found to be the most efficient catalyst for the AAC reaction, affording up to 98% product yield after being placed for 15 min, at 125 °C, in a water/acetonitrile mixture under low power (10 W) MW irradiation.

Design, Synthesis and In vitro Cytotoxicity of New 1,2,3-triazol- and Nitrostyrene Hybrids as Potent Anticancer Agents

Background:

A new series of 1,2,3-triazol-nitrostyrene derivatives was designed, synthesized, and evaluated for cytotoxic activity against Hep-2 and L929 cell lines. </P><P> Methods: The synthetic procedure started from the functionalization of 4-hydroxybenzaldehyde with propargyl bromide and a subsequent click reaction to give 1,2,3-triazole derivatives. Then, the reaction of the mentioned derivatives with nitromethane led to the formation of the title compounds in excellent yields.

Results:

Most of the compounds exhibited better cytotoxic activity with respect to the standard drug 5-fluorouracil. Among them, (E)-1-(3,4-dichlorobenzyl)-4-((4-(2-nitrovinyl)phenoxy)methyl)-1H- 1,2,3-triazole 6i (IC50 = 4.66 &#177; 1.3 &#181;M) against the Hep-2 cell line and (E)-1-(2,3-dichlorobenzoyl)- 4-((4-(2-nitrovinyl)phenoxy)methyl)-1H-1,2,3-triazole 6g (IC50 = 5.18 &#177; 0.8 &#181;M) against the L929 cell line exhibited the best cytotoxic effects.

Conclusion:

Moreover, the acridine orange/ethidium bromide double staining technique showed that the most potent compounds 6i and 6g could induce apoptosis in studied cancer cell lines.

Synthesis and crystal structures of salen-type Cu(ii) and Ni(ii) Schiff base complexes: application in [3+2]-cycloaddition and A3-coupling reactions

The synthesis and characterisation of two new salen-type Schiff base complexes of the type [Cu(L)]·0.5H₂O and [Ni(L)], and their application in the synthesis of 5-substituted 1H-tetrazoles and propargylamines are described.

The crystal structure of bis(2-(2,2,2-trifluoroacetyl)-3,4-dihydronaphthalen-1-olato-κ2O,O′)copper(II), C24H16CuF6O4

C24H16CuF6O4, triclinic, P1̄ (no. 2), a = 6.5651(7) Å, b = 9.4145(10) Å, c = 9.5014(11) Å, α = 68.668(10)°, β = 77.063(9)°, γ = 86.847(9)°, V = 532.91(11) Å3, Z = 1, R gt(F) = 0.0596, wR ref(F 2) = 0.1477, T = 293 K.