The pharmacological effects of carbon to silicon bioisosteric replacements have been widely explored in drug design and medicinal chemistry. Here, we present a systematic investigation of the impact of different silyl groups on the anticancer activity of mucobromic acid (MBA) bearing furan-2(5H)-one core. We describe a comprehensive characterization of obtained compounds with respect to their anticancer potency and selectivity towards cancer cells. All four novel compounds exert stronger antiproliferative activity than MBA. Moreover, 3b induce apoptosis in colon cancer cell lines. A detailed investigation of the mechanism of action revealed that 3b activity stems from the down-regulation of survivin and the activation of caspase-3. Furthermore, compound 3b attenuates the clonogenic potential of HCT-116 cells. Interestingly, we also found that depending on the type of the silyl group, compound selectivity towards cancer cells could be precisely controlled. Collectively, we demonstrated the utility of silyl groups for adjusting both the potency and selectivity of silicon-containing compounds. These data reveal a link between the types of silyl group and compound potency, which could have bearings for the design of novel silicon-based anticancer drugs.

3,4-Dichloro-5-hydroxy-2(5H)-furanone and its dibromo analog are highly reactive molecules. Both are members of the 2(5H)-furanone family, which are important as pharmacophores present in drugs and natural products. Compounds possessing the 2(5H)-furanone skeleton isolated from plants and marine organisms exhibit bioactivity against various microorganisms and viruses and can also be used in other medical treatments. The structures of these 3,4-dihalo-2(5H)-furanones cause their high reactivity due to the presence of a carbonyl group on the C2 carbon conjugated with a double bond and a hydroxyl group on the C5 carbon. Two labile halogen atoms on carbons 3 and 4 offer additional possibilities for the introduction of other substituents. These structural features make 3,4-dihalo-5-hydroxy-2(5H)-furanones versatile reactants in chemical synthesis. In this review, we present methods of 3,4-dihalo-5-hydroxy-2(5H)-furanone synthesis, their applications as substrates in various chemical transformations, and examples of their biologically active derivatives.

The addition of 2-amino-1,3,4-thiadiazole derivatives with parallel iodination of differently protected glycals has been achieved using a double molar excess of molecular iodine under mild conditions. The corresponding thiadiazole derivatives of N-glycosides were obtained in good yields and anomeric selectivity. The usage of iodine as a catalyst makes this method easy, inexpensive, and successfully useable in reactions with sugars. Thiadiazole derivatives were tested in a panel of three tumor cell lines, MCF-7, HCT116, and HeLa. These compounds initiated biological response in investigated tumor models in a different rate. The MCF-7 is resistant to the tested compounds, and the cytometry assay indicated low increase in cell numbers in the sub- G1 phase. The most sensitive are HCT-116 and HeLa cells. The thiadiazole derivatives have a pro-apoptotic effect on HCT-116 cells. In the case of the HeLa cells, an increase in the number of cells in the sub-G1- phase and the induction of apoptosis was observed.

In the present study we tested, using the microscale thermophoresis technique, a small library of thionocarbamates, thiolocarbamates, sulfide and disulfide as potential lead compounds for SARS-CoV-2 Mpro drug design. The successfully identified binder is a representative of the thionocarbamates group with a high potential for future modifications aiming for higher affinity and solubility. The experimental analysis was extended by computational studies that show insufficient accuracy of the simplest and widely applied approaches and underline the necessity of applying more advanced methods to properly evaluate the affinity of potential SARS-CoV-2 Mpro binders.

Dimers of dipyridothiazines with an m-xylene moiety are presented in terms of a comparative analysis with anticancer active structural analogs containing a lutidine system. The synthesis of new isomeric dimers was described, the structure of which was confirmed by ¹H, ¹³C and 2D NMR, and HR MS spectroscopic methods. The preliminary prediction of the pharmacological profile using the Way2Drug server indicated the anticancer potential of the tested derivatives. In vitro biological activity tests were performed on a normal skin cell line (HaCaT) and five cancer cell lines, including human primary colon cancer (SW480), human metastatic colon cancer (SW620), human breast adenocarcinoma (MDA-MB-231), human lung carcinoma (A-549), and human glioblastoma (LN-229), which indicated low cytotoxic activity. In order to explain the surprisingly low activity, a comparative structural analysis of the tested analogs compared to the dimers with the lutidine system was performed using quantum mechanics and molecular docking in relation to histone deacetylase. Molecular docking indicated the different binding sites of the analyzed dimers, which explained the differences in the activity.

Heterocyclic compounds have enormous pharmacological potential and therefore play a key role in the design of new drugs. Dipyridothiazines, both heterocyclic compounds and phenothiazine derivatives, exhibit promising anticancer, immunostimulatory, and antioxidant activities. The aim of this study was to design, synthesize, and evaluate the cytotoxicity of new 10-heteroaryl dipyridothiazines based on 2,7- and 3,6-diazaphenothiazine cores. The structural characterization of the new compounds was confirmed by spectroscopic methods. Cytotoxicity analysis was performed using the MTT assay against human keratinocytes (HaCaT) and two types of cancer cell lines: breast cancer (MDA-MB-231), lung carcer (A-549). The reference drugs used in the study were doxorubicin and cisplatin. The group of derivatives studied included active compounds as well as inactive derivatives. In order to explain differences in an activity level, molecular modelling supported by molecular dynamics was performed on histone deacetylase 6 (HDAC6), a known therapeutic target associated with oncogenic transformation and cancer metastasis. Molecular docking indicated that the derivative formed on the 2,7-diazaphenothiazine core is a more potent HDAC6 inhibitor, characterized by more stable binding and more favourable complex energy, despite minimal structural differences compared to the compound formed on the 3,6-diazaphenothiazine core. A preliminary SAR analysis was performed.