The 1,4-disubstituted 1,2,3-triazole ligand prepared by click chemistry 1-(2-picolyl)-4-phenyl-1H-1,2,3-triazole (ppt) was investigated as novel chelating ligand for Ru(II) complexes with potential antitumor activity. The preparation and structural characterization, mainly by NMR spectroscopy in solution and by X-ray crystallography in the solid state, of four new Ru(II) complexes is reported: two isomeric Ru-dmso compounds, trans,cis-[RuCl(2)(dmso-S)(2)(ppt)] (1) and cis,cis-[RuCl(2)(dmso-S)(2)(ppt)] (2), and two half-sandwich Ru-[9]aneS(3) coordination compounds, [Ru([9]aneS(3))(dmso-S)(ppt)][CF(3)SO(3)](2) (3) and [Ru([9]aneS(3))Cl(ppt)][CF(3)SO(3)] (4). In all compounds ppt firmly binds to ruthenium in a bidentate fashion through the pyridyl nitrogen atom and the triazole N2, thus forming a puckered six-membered ring. The chemical behavior in aqueous solution of the water-soluble complexes 3 and 4 was studied by UV-Vis and NMR spectroscopy and compared to that of the previously described organometallic analogue [Ru(η(6)-p-cymene)Cl(ppt)][Cl] (5) in view of their potential antitumor activity. Compounds 3-5 were tested also in vitro for cytotoxic activity against two human cancer cell lines, one sensitive and one resistant to cisplatin, in comparison with cisplatin. Compound 4, the one that aquates faster, was found to be more cytotoxic than cisplatin against human lung squamose carcinoma cell line (A-549).

Chalcones (natural or synthetic derivatives) are aromatic ketones possessing a central backbone that form a core for variety important compounds with different substitutions. Recent scientific advances show that chalcones exhibit different bio-medical activities, including antiviral, which is related to the variety substitutions. This review provides general information on the origin, sources, virucidal and direct antiviral properties of chalcones in vitro, as well as a brief overview of the possible application and molecular modes of action of these compounds. The antiviral effect of chalcones probably results from the disruption of the different stage of viral replication cycle, inhibition of viral or cell enzymes, induction of apoptosis and others. Structural requirements for antiviral activities vary according to the mechanisms of action. Based on the published information, it could be considered that synthetic chalcones are very perspective antiviral candidates and deserve further studies for elucidating of their pharmacological potential.

Graptopetalum paraguayense E. Walther (GP) belongs to the Crassulaceae family and has several health benefits. In the present study we evaluated the cytotoxic, anti-Herpes Simplex virus (HSV) and antibacterial activities of a total methanol/water GP extract. The results from the cytotoxicity investigation of the tested extract showed a high cell tolerable concentration range. The GP extract demonstrated a significant inhibitory effect on the wild-type HSV-1 strain Victoria in a concentration of 0.0001 mg/mL equal to the maximal nontoxic concentration (with 97.5% protection of the cells). Regarding the acyclovir-resistant mutant HSV-2 strain PU and wild-type HSV-2 strain Bja, the antiviral activity and selectivity of the extract were very low, with EC 50 values from 0.1 to 0.01 mg/mL, and the selectivity index ranging from 25 to 250, respectively. The GP extract exhibited selective inhibitory activity also on the growth of Gram-positive bacterial pathogens, with Staphylococcus aureus being most sensitive. It also prevented the formation of MRSA biofilm up to 50% at a concentration of 1.6 mg/mL and up to 90% at a concentration of 2.5 mg/mL. The anti-herpetic and antibacterial activities demonstrated in our investigation are probably related to the presence of phenols, and in particular gallic acid. The antimicrobial activity of the GP extract holds a promise for the future development of nutrition supplements based on G. paraguayense and therefore warrants further studies aimed at isolating biologically active compounds or mixtures thereof with subsequent in-depth investigation of their anti-HSV and antibacterial mechanisms of action.

The danger of the emergence of new viral diseases and their rapid spread demands apparatuses for continuous rapid monitoring in real time. This requires the creation of new bioanalytical methods that overcome the shortcomings of existing ones and are applicable for point-of-care diagnostics. For this purpose, a variety of biosensors have been developed and tested in proof-of-concept studies, but none of them have been introduced for commercial use so far. Given the importance of the problem, in this study, long-period grating (LPG) and surface plasmon resonance (SPR) biosensors, based on antibody detection, were examined, and their capabilities for SARS-CoV-2 structural proteins detection were established. Supersensitive detections of structural proteins in the order of several femtomoles were achieved by the LPG method, while the SPR method demonstrated a sensitivity of about one hundred femtomoles. The studied biosensors are compatible in sensitivity with ELISA and rapid antigen tests but, in contrast, they are quantitative, which makes them applicable for acute SARS-CoV-2 infection detection, especially during the early stages of viral replication.

The cytotoxicity and the antivirus activity of native hemocyanin, RtH, derived from the Bulgarian marine mollusk Rapana thomasiana and its structural isoform, RtH2, against HSV replication was evaluated on three HSV strains Ð two wt strains, TM (HSV 1) and Bja (HSV 2), and one ACV R mutant with tk gene mutation, DD (HSV 2). The experiments were performed on continuous RD 64 cells and three HSV 1 and HSV 2 strains were used, two mutants sensitive to acyclovir and one resistant mutant.Both compounds were found to be effective inhibitors of wt HSV replication. Both compounds did not exhibit any effect on the infectious virus yield on ACV R mutant. The most promising, active and selective, anti-HSV agent, especially to genital herpes virus, was found to be the functional unit of native hemocyanin Ð RtH2. RtH2 did not induce apoptosis/ necrosis 8 h after virus infection and the target of its action, was found to be the viral but not the host cell DNA.