ABEER ABDULJALEEL IBRAHIM

Published by

Pharmaceuticals 2021, 14(6), 509

Summary

In this study, a platinum(II) complex ([Pt(H2L)(PPh3)] complex) containing a thiocarbohydrazone as the ligand was tested as an anti-proliferative agent against ovarian adenocarcinoma (Caov-3) and human colorectal adenocarcinoma (HT-29) through MTT assays. Apoptotic markers were tested by the AO/PI double staining assay and DNA fragmentation test. Flow cytometry was conducted to measure cell cycle distribution, while the p53 and caspase-8 pathways were tested via immunofluorescence assay. Results demonstrated that the cytotoxic effect of the Pt(II)-thiocarbohydrazone complexes against Caov-3 and HT-29 cells was highly significant, and this effect triggered the activation of the p53 and caspase-8 pathways. Besides, apoptosis stimulated by the Pt(II)-thiocarbohydrazone complex was associated with cell cycle arrest at the G0/G1 phase. These findings suggest that the target complex inhibited the proliferation of Caov-3 and HT-29 cells, resulting in the arrest of the cell cycle and induction of apoptosis via the stimulation of the p53 and caspase-8 pathways. The present data suggests that the Pt(II)-thiocarbohydrazone complex could also be a promising chemotherapeutic agent for other types of cancer cells. Keywords: Pt(II) complex; anticancer activity; apoptosis; DNA fragmentation; p53; caspase-8

Published by

Royal Society of Chemistry

Summary

A new thiosemicarbazone (LH2) derived from indole-7-carbaldehyde was synthesized and reacted with ZnII, CdII, PdII and PtII salts. The reactions with zinc and cadmium salts in 2 : 1 (ligand–metal) molar ratio afforded complexes of the type MX2(LH2)2, (X = Cl, Br or OAc), in which the thiosemicarbazone acts as a neutral S-monodentate ligand. In the presence of potassium hydroxide, the reaction of LH2 with ZnBr2 resulted in deprotonation of the thiosemicarbazone at the hydrazine and indole nitrogens to form Zn(L)(CH3OH). The reaction of LH2 with K2PdCl4 in the presence of triethylamine, afforded Pd(L)(LH2) which contains two thiosemicarbazone ligands: one being dianionic N,N,S-tridentate while the other one is neutral S-monodentate. When PdCl2(PPh3)2 was used as the PdII ion source, Pd(L)(PPh3) was obtained. In a similar manner, the analogous platinum complex, Pt(L)(PPh3), was synthesized. The thiosemicarbazone in the latter two complexes behaves in a dianionic N,N,S-tridentate fashion. The platinum complex was found to have significant cytotoxicity toward four cancer cells lines, namely MDA-MB-231, MCF-7, HT-29, and HCT-116 but not toward the normal liver WRL-68 cell line. The apoptosis-inducing properties of the Pt complex was explored through fluorescence microscopy visualization, DNA fragmentation analysis and propidium iodide flow cytometry.

Published by

Elsevier

Summary

A novel series of mixed-ligand complexes of the type, [ML1(L2)3]Clx [M= Cr(III), Fe(III), Co(II),Ni(II), Cu(II), Cd(II) and Hg(II), n = 2, 3], was synthesized using Schiff base (HL1) as main ligand, nicotinamide (L2) as secondary ligand, and the corresponding metal ions in 1:3:1 molar ratio. The main ligand, HL1 was prepared by the interaction of ampicillin drug and 4-chlorobenzophenone. The synthesized mixed ligand complexes were characterized by elemental analysis, UV-Vis, FT-IR,1H-NMR,13C-NMR and TG/DTG studies. In the mixed-ligand complexes, the Schiff base ligand, HL1 showed coordination to the central metal ion in tridentate manner via azomethine nitrogen, β-lactam ring oxygen and deprotonated carboxylic oxygen atoms, whereas the secondary ligand L2 (nicotinamide, Nam) coordinated through pyridine nitrogen atoms. The synthesized complexes exhibited significant antimicrobial activity when evaluated against P. pseudomonas, E. coli, S. aureus and B. subtilis microbes. The DFT calculations were also carried out to ascertain the bonding insights into the structure. In addition, molecular docking analysis was performed carried out to know the interactions between complexes and their probable binding sites in penicillin binding protein (PBP2). Moreover, drug-likeness and toxicity of the compounds were also performed to predict the suitability of the complexes as drugs.

Published by

Pergamon

Summary

A new thiocarbohydrazone (LH4) derived from indole-7-carbaldehyde was synthesized and reacted with NiII, PdII, PtII, CuI and AgI salts to bind the metals in various coordination fashions, forming complexes with different nuclearities. The reaction with CuCl in the presence of PPh3 produced a dinuclear CuI complex with the formula [Cu2Cl2(LH4)2(PPh3)2], in which LH4 binds the metals as a neutral μ2-S-donor ligand. The reaction of the thiosemicarbazone with AgI resulted in the formation of a hexanuclear complex featuring an Ag6S6 core. The ligand in this complex is monoanionic and uses the sulfur and a hydrazinic nitrogen atom in binding to the metals. The reaction of LH4 with [MCl2(PPh3)2] (M = NiII, PdII and PtII) at room temperature yielded complexes of the type [M(LH2)(PPh3)]. The thiocarbohydrazone in these complexes takes advantage of one indole N atom donor to act as a dianionic NNS tridentate ligand. A modification of the conditions of the reaction with the PdII salt led to the formation of the dinuclear complex [Pd2Cl(LH)(PPh3)3]. In this molecule, the thiocarbohydrazone is triply deprotonated and chelates one metal center by its dianionic NNS pocket, while coordinating the second metal ion through a hydrazinic N atom. The structure of the molecules was studied by X-ray crystallography and NMR spectroscopy.

Published by

Elsevier

Summary

There is no doubt that food safety has a knock-on effect on our lives from different perspectives. the analysis of foodborne pathogenic bacteria, antibiotics, pesticides, mycotoxins, and biotoxins can broaden our horizons about foodborne diseases and economic barriers. Recently, versatile biosensors based on magnetic nanomaterials (MNMs) and aptamer (Apt) have attracted considerable attention in terms of food analysis due to their several advantages such as sensitivity, fast response time, selectivity, and affordability.