Synthesis, characterization and biological activity of diorganotin complexes with ONO terdentate Schiff base

Transition metal complexes of hydrazones as potential antimicrobial and anticancer agents: A short review

Hydrazones display an interesting profile of biological activities, which includes mainly antimicrobial and antiproliferative properties. Hydrazones also play an important role in the synthesis of heterocyclic rings and in coordination chemistry. Currently, the synthesis of complexes of hydrazones with transition metals is quite frequently reported in the scientific literature. The interest in this topic is largely due to diverse biological activities of the metal complexes of hydrazones that in some cases are much more effective than hydrazones themselves. This review focuses on the complexes of hydrazones with transition metals which display antibacterial, antitubercular, antifungal and anticancer activities. In the following subchapters devoted to a given activity, an attempt has been made to present the most active complexes of hydrazones, their trends in their activity and application in medicinal chemistry. The paper presents the literature data from 2009 to 2023. This review constitutes a useful guide for the researchers who intend to synthesize and investigate complexes of hydrazones in terms of their antimicrobial and anticancer activities.

Crystal structure of aqua-chlorido-(4-fluorobenzyl-κC)-(N′-(4-methoxy-2-oxidobenzylidene)-3-hydroxy-2-naphthohydrazidato-κ3N,O,O′)tin(IV), C26H22ClFN2O5Sn

C26H22ClFN2O5Sn, triclinic, P1̄ (no. 2), a = 7.1473(6) Å, b = 12.8246(11) Å, c = 13.2899(11) Å, α = 97.541(5)°, β = 94.503(6)°, γ = 96.247(5)°, V = 1195.13(18) Å3, Z = 2, Rgt(F) = 0.0325, wRref(F2) = 0.0756, T = 296(2) K.

Crystal structure of benzyl-chlorido-(4-chloro-N-[(2-oxidophenyl)methylidene]benzenecarbohydrazonato)-methanol-tin(IV), C22H20Cl2N2O3Sn

C22H20Cl2N2O3Sn, orthorhombic, P212121 (no. 19), a = 8.1234(3) Å, b = 10.7966(3) Å, c = 24.9785(8) Å, V = 2190.74(12) Å3, Z = 4, Rgt(F) = 0.0271, wRref(F2) = 0.0645, T = 293(2) K.

Crystal structure of chlorido-methanol-(N-(2-(oxy)-3-methoxybenzylidene)pyridine-4-carbohydrazonato-κ3 O,N,O′)-(4-methylphenyl)methyl-tin(IV), C23H24ClN3O4Sn

C23H24ClN3O4Sn, triclinic, P1̄ (no. 2), a = 9.7536(2) Å, b = 10.0755(2) Å, c = 12.4215(3) Å, α = 84.928(2)°, β = 72.544(2)°, γ = 74.382(2)°, V = 1121.44(4) Å3, Z = 2, R gt(F) = 0.021, wR ref(F 2) = 0.054, T = 100(2) K.

Crystal structure of (N-(3-ethoxy-2-oxidobenzylidene)-4-fluorobenzohydrazonato-κ3 N,O,O′)-diphenyltin(IV), C28H23FN2O3Sn

C28H23FN2O3Sn, orthorhombic, Pbca (no. 61), a = 16.0887(2) Å, b = 14.5333(2) Å, c = 20.5550(2) Å, V = 4806.21(10) Å3, Z = 8, R gt(F) = 0.0199, wR ref(F 2) = 0.0596, T = 100(2) K.

Crystal structure of {N-(3-ethoxy-2-oxidobenzylidene)-4-fluorobenzohydrazonato-κ3 O,N,O′}dimethyltin(IV), C18H19FN2O3Sn

C18H19FN2O3Sn, monoclinic, C2/c (no. 15), a = 27.1120(3) Å, b = 9.5721(1) Å, c = 13.3072(1) Å, β = 98.271(1)°, V = 3417.55(6) Å3, Z = 8, R gt(F) = 0.016, wR ref(F 2) = 0.043, T = 100(2) K.

N'-[1-(5-Bromo-2-hy-droxy-phen-yl)ethyl-idene]isonicotinohydrazide monohydrate: crystal structure and Hirshfeld surface analysis

In the title isonicotinohydrazide hydrate, C14H12BrN3O2·H2O {systematic name: N'-[(1E)-1-(5-bromo-2-hy-droxy-phen-yl)ethyl-idene]pyridine-4-carbohydrazide monohydrate}, the central CN2O region of the organic mol-ecule is planar and the conformation about the imine-C=N bond is E. While an intra-molecular hy-droxy-O-H⋯N(imine) hydrogen bond is evident, the dihedral angle between the central residue and the benzene rings is 48.99 (9)°. Overall, the mol-ecule is twisted, as seen in the dihedral angle of 71.79 (6)° between the outer rings. In the crystal, hydrogen-bonding inter-actions, i.e. hydrazide-N-H⋯O(water), water-O-H⋯O(carbon-yl) and water-O-H⋯N(pyrid-yl), lead to supra-molecular ribbons along the a-axis direction. Connections between these, leading to a three-dimensional architecture, are mediated by Br⋯Br halogen bonding [3.5366 (3) Å], pyridyl-C-H⋯O(carbon-yl) as well as weak π-π inter-actions [inter-centroid separation between benzene rings = 3.9315 (12) Å]. The Hirshfeld surface analysis reveals the importance of hydrogen atoms in the supra-molecular connectivity as well as the influence of the Br⋯Br halogen bonding.

[N'-(4-Dec-yloxy-2-oxido-benzyl-idene)-3-hy-droxy-2-naphtho-hydrazidato-κ3N,O,O']di-methyl-tin(IV): crystal structure and Hirshfeld surface analysis

The title diorganotin compound, [Sn(CH3)2(C28H32N2O4)], features a distorted SnC2NO2 coordination geometry almost inter-mediate between ideal trigonal-bipyramidal and square-pyramidal. The dianionic Schiff base ligand coordinates in a tridentate fashion via two alkoxide O and hydrazinyl N atoms; an intra-molecular hy-droxy-O-H⋯N(hydrazin-yl) hydrogen bond is noted. The alk-oxy chain has an all-trans conformation, and to the first approximation, the mol-ecule has local mirror symmetry relating the two Sn-bound methyl groups. Supra-molecular layers sustained by imine-C-H⋯O(hy-droxy), π-π [between dec-yloxy-substituted benzene rings with an inter-centroid separation of 3.7724 (13) Å], C-H⋯π(arene) and C-H⋯π(chelate ring) inter-actions are formed in the crystal; layers stack along the c axis with no directional inter-actions between them. The presence of C-H⋯π(chelate ring) inter-actions in the crystal is clearly evident from an analysis of the calculated Hirshfeld surface.

Anticancer activity of a monobenzyltin complex C1 against MDA-MB-231 cells through induction of Apoptosis and inhibition of breast cancer stem cells

In the present study, we examined the cytotoxic effects of Schiff base complex, [N-(3,5-dichloro-2-oxidobenzylidene)-4-chlorobenzyhydrazidato](o-methylbenzyl)aquatin(IV) chloride, and C1 on MDA-MB-231 cells and derived breast cancer stem cells from MDA-MB-231 cells. The acute toxicity experiment with compound C1 revealed no cytotoxic effects on rats. Fluorescent microscopic studies using Acridine Orange/Propidium Iodide (AO/PI) staining and flow cytometric analysis using an Annexin V probe confirmed the occurrence of apoptosis in C1-treated MDA-MB-231 cells. Compound C1 triggered intracellular reactive oxygen species (ROS) production and lactate dehydrogenase (LDH) releases in treated MDA-MB-231 cells. The Cellomics High Content Screening (HCS) analysis showed the induction of intrinsic pathways in treated MDA-MB-231 cells, and a luminescence assay revealed significant increases in caspase 9 and 3/7 activity. Furthermore, flow cytometric analysis showed that compound C1 induced G0/G1 arrest in treated MDA-MB-231 cells. Real time PCR and western blot analysis revealed the upregulation of the Bax protein and the downregulation of the Bcl-2 and HSP70 proteins. Additionally, this study revealed the suppressive effect of compound C1 against breast CSCs and its ability to inhibit the Wnt/β-catenin signaling pathways. Our results demonstrate the chemotherapeutic properties of compound C1 against breast cancer cells and derived breast cancer stem cells, suggesting that the anticancer capabilities of this compound should be clinically assessed.

Mononuclear and three-dimensional metal complexes based on a multidentate hydrazone ligand

A potentially pentadentate hydrazone ligand,N′-[1-(pyrazin-2-yl)ethylidene]nicotinohydrazide (HL), was prepared from the condensation reaction of nicotinohydrazide and acetylpyrazine. Reactions of HLwith MnCl2, Mn(CH3COO)2and Cd(CH3COO)2afforded three metal complexes, namely dichlorido{N′-[1-(pyrazin-2-yl-κN1)ethylidene]nicotinohydrazide-κ2N′,O}manganese(II), [MnCl2(C12H11N5O)], (I), bis{N′-[1-(pyrazin-2-yl-κN1)ethylidene]nicotinohydrazidato-κ2N′,O]manganese(II), [Mn(C12H10N5O)2], (II), and poly[[(acetato-κ2O,O′){μ3-N′-[1-(pyrazin-2-yl-κ2N1:N4)ethylidene]nicotinohydrazidato-κ3N′,O:N1}cadmium(II)] chloroform disolvate], {[Cd(C12H10N5O)(CH3COO)]·2CHCl3}n, (III), respectively. Complex (I) has a mononuclear structure, the MnIIcentre adopting a distorted square-pyramidal coordination. Complex (II) also has a mononuclear structure, with the MnIIcentre occupying a special position (C2symmetry) and adopting a distorted octahedral coordination environment, which is defined by two O atoms and four N atoms from twoN′-[1-(pyrazin-2-yl)ethylidene]nicotinohydrazidate (L−) ligands relatedviaa crystallographic twofold axis. Complex (III) features a unique three-dimensional network with rectangular channels, and theL−ligand also serves as a counter-anion. The coordination geometry of the CdIIcentre is pentagonal bipyramidal. This study demonstrates that HL, which can act as either a neutral or a mono-anionic ligand, is useful in the construction of interesting metal–organic compounds.

Dimeric diorganotin(iv) complexes with arylhydrazones of β-diketones: synthesis, structures, cytotoxicity and apoptosis properties

The apoptosis induction of the new dimeric diorganotin(iv) complexes correlates with the cytotoxicity. The mechanism of KB cell death might occur mainly by means of early apoptosis.