Although COVID-19 is not a pandemic anymore, the virus frequently mutates, resulting in new strains and presenting global public health challenges. The lack of oral antiviral drugs makes it difficult to treat him, which makes the creation of broadly acting antivirals necessary to fight current and next epidemics of viruses. Using the molecular docking approach, 118 compounds derived from marine organisms and 92 previously synthesized compounds were screened to assess their binding affinity for the main protease and papain-like protease enzymes of SARS-CoV-2. The best candidates from the xanthene, benzoxazole, and coumarin classes were identified. Marine-derived compounds showed slightly better potential as enzyme inhibitors, though the binding affinities of synthesized compounds were similar, with the best candidates displaying affinity values between 0.2 and 0.4 mM. Xanthenes, among both marine origin and synthesized compounds, emerged as the most promising scaffolds for further research as inhibitors. The papain-like protease was found to be more druggable than the main protease. Additionally, all top candidates met the criteria for various drug-likeness properties, indicating good oral bioavailability and low risk of adverse effects. This research provides valuable insights into the comparative affinities of marine origin and synthesized compounds from the xanthene, coumarin, and benzoxazole classes, highlighting promising candidates for further in vitro and in vivo studies.

BACKGROUND Computational research plays an important role in predicting the chemical and physical properties of biologically active compounds important in future structural modifications to improve or modify biological activity. OBJECTIVE This research focuses on quantum chemical and spectroscopic investigations properties of synthesized 4-hydroxycoumarin derivatives. METHODS Quantum chemical calculations were obtained using B3LYP, HF, and M06-2x level methods with the 6-31++G (d,p) basis set. Afterward, IR, 1H, 13C, UV-Visible experimentally parameters were compared with the results obtained using the B3LYP/6-31+G*(d) basis set of the molecules to be able to characterize the structures. RESULTS Based on the quantum chemical calculations compound with acetamido group on the phenyl ring is the most reactive, and compound with nitro substituent is the least reactive and the the strongest electrophile among tested compounds. With the exception of compounds with dimethylamino group, all other compounds have a pronounced tautomer between between OH and C = O group. The calculated and experimental values are in agreement with each other. CONCLUSION The molecular structure in the ground state of six 3-cinnamoyl 4-hydroxycoumarin derivatives was optimized using density functional theory. The observed and computed values were compared and it can be concluded that the theoretical results were in good linear agreement with the experimental data.

Xanthene derivatives are an important class of heterocyclic compounds with a wide spectrum of pharmacological activities. In our previous investigations, we found the good antiproliferative activity of two xanthene derivatives, with minimal toxicity investigated by in vitro tests. In this study, we tested the interaction of compound 1 (powerful potent antiproliferative compound) with calf thymus DNA (CT-DNA) under physiological conditions by spectrophotometric titration. The probable prediction of binding and the type of interaction forces involved in the arrangement between xanthene derivatives and CT-DNA were explored also through molecular docking studies. The results indicated that compound 1 interacts with CT-DNA by grove binding. The binding constant was found to be 2.5 ∙ 10 4 M −1 indicating the non-covalent binding of compound 1 to CT-DNA. Docking study results proposed possible binding modes, with binding energies of −9.39 and −8.65 kcal mol −1 for compounds 1 and 2, respectively, which supported previously obtained in vitro results for antiproliferative activity. In addition to experimental investigation, density functional theory (DFT) calculation with B3LYP/6-31G*, B3LYP/6-31G**, and B3LYP/6-31+G* levels of theories was performed on compounds 1 and 2 to obtain optimised geometry, spectroscopic and electronic properties. These studies could help in understanding the mechanisms of toxicity, resistance, side effects of xanthene derivatives, and their binding action mechanism to DNA

Iron deficiency anemia is one of the main health issues that has an impact on cognitive function, physical ability, immune function, and reproductive performance. Therefore, this study focused on the determination of iron content in leafy plants cultivated in Bosnia and Herzegovina, and the average daily intake of iron via consumption of these plants. The plant samples were prepared by wet digestion with nitric acid (HNO3), and iron content was determined using flame atomic absorption spectrometry (FAAS). The mean concentration of Fe ranged from 41.97 mg/kg for Brassica oleracea var. acephala to 338.73 mg/kg for Spinacia oleracea. Daily intakes for different leafy plants were also calculated. The leafy plants were arranged by daily iron intake in the following decreasing order Spinacia oleracea > Beta vulgaris > Atriplex hortensis > Urtica dioica > Brassica oleracea var. acephala. Results from this study indicate that leafy plants can be a significant source of iron. The findings conclusively suggest that our local leafy plants are good source of iron through diet.

Aims: The aim of this study was to conduct antimicrobial analysis on novel Schiff base-derived cobalt(II) complexes (Co(L1) 2 and Co(L2) 2 )

Ash is a by-product of wood biomass combustion that must be removed daily from stoves or fireplaces. Therefore, operators or owners are exposed to the potential impact of ash. The goal of this study was to determine whether heavy metal present in wood pellet ash posed a health concern to stove operators/owners. The risk assessment procedure was carried out in several steps, including exposure evaluation, toxicity evaluation, and risk categorisation. The hazard coefficient (HQ) and non-carcino genic hazard index (HI) were calculated for Cd, Cr, Cu, Ni, Pb, and Zn. HQ had the highest value for the ingestion pathway (3.62 ∙ 10 −6 ), and the value for non-carcinogenic HI was 3.70 ∙ 10 −6 . The value HI < 1 suggests that there is no risk to operator health related to heavy metals in analysed wood pellets ash. The carcinogenic risk (CR) was calculated for Ni, Pb, Cr, and Cd, and the values were within the permitted limits. The risk assessment based on HI and CR indicators proved that there was no significant health concern regarding exposure to the analysed ashes.