A comparative study of novel ruthenium(III) and iron(III) complexes containing uracil; docking and biological studies

Structural and biological studies were conducted on the novel complexes [Fe(U)2(H2O)2]Cl3 (FeU) and [Ru(U)2(H2O)2]Cl3 (RuU) (U = 5,6-Diamino-1,3-dimethylpyrimidine-2,4(1H,3H)-dione) to develop an anticancer drug candidate. The two complexes have been synthesized and characterized. Based on our findings, these complexes have octahedral geometry. The DNA-binding study proved that both complexes coordinated with CT-DNA. The docking study confirmed the potency of both complexes in downregulating the topoisomerase I protein through their high binding affinity. Biological studies have established that both complexes can act as potent anticancer agents against three cancer cell lines. RuU or FeU complexes induce apoptosis in breast cancer cells by increasing caspase9 protein and inhibiting proliferating cell nuclear antigen (PCNA) activity. In addition, both complexes down-regulate topoisomerase I expression in breast cancer cells. Therefore, the RuU and FeU complexes' anticancer activities were mediated via both apoptosis induction and topoisomerase I down-regulation. In conclusion, both complexes have dual anticancer activity pathways that may be responsible for the selective cytotoxicity of the complexes. This makes them more suitable for the development of novel cancer treatment strategies.

Tuning the structural and catalytic properties of copper(II)-based complexes containing pyridine-2,6-diimines

Four mononuclear penta coordinated copper(II) chelates, [CuLⁿBr₂] nH₂O, containing the tridentate neutral ligands, pyridine-2,6-diimine (Lⁿ), were prepared via the template technique. Analytical and several physicochemical methods have been used to characterize the prepared metal chelates. Square-pyramidal stereochemistry was described to the current copper(II) complexes. DFT technique has been applied to optimize the structure of the running diimines and their corresponding copper-based compounds. Ligand substitution study performed to link the catalytic potency of the candidate oxidase mimics and their lability characters. Spectral investigations reveal that nature of substituents of the chelated ligands effectively tuning the Lewis acidity of copper(II) centers. Biomimetics of redox proteins specifically containing copper were examined towards the aerobic oxidation of polyphenol. Kinetic studies with the stopped-follow technique showed a close association between the Lewis acidity of the copper(II) nuclei of the prepared chelates and their oxidase-like activity. The catalytic activity of the natural enzyme (catechol oxidase from sweet potatoes) measured and compared with that for the present Cu^II chelates. The thermodynamic parameter drive force (ΔG° or λ) of the performed oxidation processes was determined from the values of redox potential of the chemical species involved in these catalytic reactions. The proposed catalytic reactions pathways have been discussed based on the outcomes of the kinetic investigations.Communicated by Ramaswamy H. Sarma.

Ruthenium(III) Based Diimine Complexes; Synthesis, Characterization, PXRD Study and Catalytic Hydrogenation of Cyclohexene.. [DOI: 10.21203/rs.3.rs-385877/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

This study deals with preparation and characterization of a group of RuIII-chelates contains tetradentate diimine ligands. These quadridentate ligands are derived from 2-OH-1-naphthaldehyde and a number of aliphatic diamines where the number of methylene groups between the two azomethine nitrogen donors varied from two to six are the components of quadridentate ligands. The pure isolated compounds were subjected to several physicochemical investigations to assign their structures. Spectral and magnetic measurements suggested a distorted octahedral arrangement of the six coordinate diimine ruthenium(III) complexes. The structural optimization for one of the current RuIII-complexes was determined based on the processing of powder X-ray diffraction (PXRD) data by the computer program Expo 2014 PXRD. As well DFT calculations were applied to optimize the geometry in the case of complexes 1. The newly synthesized ruthenium(III) diimines were tested as catalysts for hydrogenation of cyclohexene. The effect of the catalyst structure and the type of catalysis as well as the nature and amount of the solvent used on the catalytic performance of the current catalysts were studied. Catalytic experiments reported that the ongoing ruthenium(III) complexes are promising precatalysts that have successfully catalyzed hydrogenation of cyclohexene by hydrogen gas under moderate process conditions. The results obtained allowed to establish a mechanism for the studied catalytic hydrogenation reactions.

The Pivotal Role Of Coconut Oil Or Liquid Paraffin As Antidote Effective In Reducing Acute Aluminum Phosphide Poisoning In Cardiogenic Shock

Introduction/Objective

Aluminum phosphide (Alp) is a self-poisoning agent for raising the mortality rates in developing countries. Alp is known as “Rice-tablet” which is a cheap solid fumigant pesticide that is used for grain preservation which becomes a common mode of suicidal attempts in the rural community in Egypt. This study aims to identify the mechanism of salient features and management strategies were carried out on acute Alp-poisoned patients at Poison-Emergency-Unit, ElBehira-Hospitals. That was performed between Jan2018-Jun2019.

Methods

Patients were subjected to a full history evaluation of age, sex, Blood gases, and ECG, were demonstrated. Patients were grouped according to their outcome into survivors and non-survivors groups.

Results

The results demonstrated that (93%) of Alp-poisoning cases by oral-ingestion as suicidal attempts which were (54%) survived while (46%) non-survived. The blood-gases were showed that over 50% of the cases had metabolic acidosis with a highly-significant difference between survivors and non-survivors. PH and HCO3 values were significantly lower in non-survivors than those in the survivor group. Furthermore, SaO2 value was significantly higher in survivors than that of non-survivors. So the managing Alp-poisoning should be started for first 6hr since exposure. Treatment includes early gastric lavage with potassium-permanganate-(1:10,000), sodium-bicarbonate or coconut-oil/liquid-paraffin. The mechanism of Alp-poisoning explained that, phosphine gas inhibits 70% of mitochondrial cytochrome-c-oxidase in myocardial-tissue by the effect of free-radicals; electrolyte disturbance, and intracellular acidosis all cause a reduction in cardiac function, and multi-organ damage. These effects may cause arrhythmia and myocarditis which may be the cause of death.

Conclusion

It was concluded that myocardial depression with shock and metabolic acidosis may lead to respiratory failure due to acute Alp-poisoning. This case study reported that coconut oil play a pivotal role in managing acute Alp- poisoning even 6h post ingestion for reducing the oxidative outcomes of phosphine and recommended as antidote for acute Alp-intoxication.