Bioactive Derivatives Research Articles

FeCl3 ⋅ 6H2O Mediated Sequential Oxidative Cleavage and Spiro Coupling of Peroxyoxindole with Cyclic‐1,3‐diketone/1‐Naphthol for the Synthesis of Spirooxindolo‐Xanthene Derivatives

AbstractHerein, an efficient approach to synthesize various hexahydro‐1H‐xanthene‐1,8‐dione or dibenzo xanthene containing bioactive spirooxindole derivatives is reported by using FeCl3 ⋅ 6H2O mediated spiro coupling of 1,3‐diketone or naphthalene‐1‐ol with peroxyoxindole. This new approach proceeds via a sequential oxidative cleavage of the C−C bond of peroxyoxindoles to generate the isatin intermediate and further reaction with two molecules of cyclic‐1,3 diketones through a series of reactions such as Knoevenagel condensation, Michael addition, and dehydration in one‐pot conditions. Furthermore, this sequential reaction of peroxyoxindole with malononitrile afforded 2‐(2‐oxoindolin‐3‐ylidene)malononitriles in very good yields in the presence of the most abundant Fe‐catalyst. A plausible mechanistic pathway in this transformation has been supported with experimental evidence and control experiments.

Synthesis, spectroscopic, DFT calculations, biological activity, SAR, and molecular docking studies of novel bioactive pyridine derivatives

Enaminonitrile pyridine derivative was used as a precursor for preparation of fourteen heterocyclic compounds using both conventional thermal and microwave techniques. Diverse organic reagents, such as chloroacetyl chloride, acetic anhydride, chloroacetic acid, carbon disulfide, p-toluene sulfonyl chloride, maleic anhydride, phthalic anhydride, were used. The chemical formulae and structures of isolated derivatives were obtained using different analytical and spectroscopic techniques such as IR, 1H-, 13C-NMR as well as mass spectrometry. The spectroscopic analyses revealed diverse structure arrangements for the products. Molecular structure optimization of certain compounds were performed by the density functional theory (DFT/B3LYP) method and the basis set 6–31 G with double zeta plus polarization (d,p). The antimicrobial inhibition and the antioxidant activity of the reported compounds were screened. Compounds 5, 6, 11 and 13 exhibited the highest antibacterial inhibition, while compound 8 gave the highest scavenging activity (IC50 43.39 µg/ml) against the DPPH radical. Structure–activity relationship of the reported compounds were correlated with the data of antibacterial and the antioxidant activity. The global reactivity descriptors were also correlated with the biological properties of compounds. The molecular docking studies of reported compounds were investigated, and the analysis showed that the docked compounds have highly negative values for the functional binding scores. The binding interaction was found to be correlated with the substituent fragments of the compounds.

Therapeutic potentialities of green tea (Camellia sinensis) in ischemic stroke: biochemical and molecular evidence.

Ischemic stroke is a leading cause of disability and death in patients. Despite considerable recent advances in the treatment of ischemic stroke, only a limited number of effective neuroprotective agents are available for stroke. Green tea (Camellia sinensis) is a popular herbal plant, and numerous studies have indicated its health benefits for several diseases. Green tea is of interest due to its high content of catechin derivatives, including epicatechin, gallocatechin, epicatechin gallate, epigallocatechin, and epigallocatechin-3-gallate. This review tried to develop a feasible background for the potential effects of green tea and its bioactive derivatives concerning protection against ischemic stroke. Green tea's antioxidants, anti-inflammatory, anti-apoptotic, and neuroprotective effects are believed to be efficacious in stroke treatment. Evidence supports the idea that green tea can be used to assist in treating ischemic stroke.

Effect of different stress conditions on the formation of amino acid derivatives by Brewer’s and Baker’s yeast during fermentation

The effects of environmental stresses on the formation of amino acid derivatives by Saccharomyces cerevisiae NCYC 88 and Saccharomyces cerevisiae NCYC 79 were investigated. Fermentation was performed in model systems under different temperature, pH, alcohol, phenolic, and osmotic stress conditions, as well as in beer and dough. According to stress response molecules, yeasts were more affected by osmotic, temperature, and alcohol stresses. Both yeast strains increased the formation of kynurenic acid, tryptophan ethyl ester, tryptophol, and gamma-aminobutyric acid under osmotic stress conditions in model systems. Indole-3-acetic acid was found to be higher in the ferulic acid stress dough (262 µg/kg dry weight, d.w.) compared to the control dough (132 µg/kg d.w.) at the end of the fermentation. The results may enable the development of new strategies for designing novel foods with a desired composition of bioactive amino acid derivatives.

In vitro cytotoxic effect of stigmasterol derivatives against breast cancer cells

BackgroundStigmasterol is an unsaturated phytosterol that belong to the class of tetracyclic steroids abundant in Rhoicissus tridentata. Stigmasterol is an important constituent since it has shown impressive pharmacological effects such as anti-osteoarthritis, anticancer, anti-diabetic, anti-inflammatory, antiparasitic, immunomodulatory, antifungal, antioxidant, antibacterial, and neuroprotective activities. Furthermore, due to the presence of π system and hydroxyl group, stigmasterol is readily derivatized through substitution and addition reactions, allowing for the synthesis of a wide variety of stigmasterol derivatives.MethodsStigmasterol (1) isolated from Rhoicissus tridentata was used as starting material to yield eight bio-active derivatives (2–9) through acetylation, epoxidation, epoxide ring opening, oxidation, and dihydroxylation reactions. The structures of all the compounds were established using spectroscopic techniques, NMR, IR, MS, and melting points. The synthesized stigmasterol derivatives were screened for cytotoxicity against the hormone receptor-positive breast cancer (MCF-7), triple-negative breast cancer (HCC70), and non-tumorigenic mammary epithelial (MCF-12 A) cell lines using the resazurin assay.ResultsEight stigmasterol derivatives were successfully synthesized namely; Stigmasterol acetate (2), Stigmasta-5,22-dien-3,7-dione (3), 5,6-Epoxystigmast-22-en-3β-ol (4), 5,6-Epoxystigmasta-3β,22,23-triol (5), Stigmastane-3β,5,6,22,23-pentol (6), Stigmasta-5-en-3,7-dion-22,23-diol (7), Stigmasta-3,7-dion-5,6,22,23-ol (8) and Stigmast-5-ene-3β,22,23-triol (9). This is the first report of Stigmasta-5-en-3,7-dion-22,23-diol (7) and Stigmasta-3,7-dion-5,6,22,23-ol (8). The synthesized stigmasterol analogues showed improved cytotoxic activity overall compared to the stigmasterol (1), which was not toxic to the three cell lines tested (EC50 ˃ 250 µM). In particular, 5,6-Epoxystigmast-22-en-3β-ol (4) and stigmast-5-ene-3β,22,23-triol (9) displayed improved cytotoxicity and selectivity against MCF-7 breast cancer cells (EC50 values of 21.92 and 22.94 µM, respectively), while stigmastane-3β,5,6,22,23-pentol (6) showed improved cytotoxic activity against the HCC70 cell line (EC50: 16.82 µM).ConclusionNatural products from Rhoicissus tridentata and their derivatives exhibit a wide range of pharmacological activities, including anticancer activity. The results obtained from this study indicate that molecular modification of stigmasterol functional groups can generate structural analogues with improved anticancer activity. Stigmasterol derivatives have potential as candidates for novel anticancer drugs.

Synthetic Strategies for Quinoline Based Derivatives as Potential Bioactive Heterocycles.

Quinoline derivatives are an important class of heterocyclic compounds and possess various applications in synthetic organic chemistry, medicinal chemistry, material chemistry and natural product chemistry. This review article describes the different quinoline derivatives having antimalarial, analgesic, anti-inflammatory, antineoplastic, antibacterial, antifungal, antiviral, anthelmintic, antiprotozoal, cardiovascular, CNS and other useful bioactivities. We have delineated the general synthetic routes for the synthesis of many bioactive quinoline based heterocycles. In addition to this, we have also discussed the crucial synthetic routes as well as their mechanistic paths for the formation of bioactive quinoline derivatives. The study shows that substitution at the 4 and 8- position of quinoline is more crucial for bioactivity as compared to other positions.

Sulfation of agarose with ammonium sulfamate: A combined experimental and theoretical study

Agarose sulfates are bioactive modified polysaccharides important for application. To obtain the bioactive agarose derivatives and expand the range of their potential use, the modification with some functional groups is needed. Agarose sulfates exhibit the anticoagulant, hypolipidemic, and other-type bioactivity. In this study, different methods for preparation of agarose sulfates using nontoxic ammonium sulfamate are investigated. Several activators and catalysts of the process of sulfation with ammonium sulfamate are examined. It is shown that urea does not significantly activate ammonium sulfamate in the sulfation reaction, while potassium permanganate ensures a sulfur content of up to 13.2 wt% in the synthesized agarose sulfate. When Lewis acids (titanium and aluminum oxides) are used, the sulfur content in agarose sulfates can only reach 7.3 wt%. The catalysts with the Brønsted acid sites used in the synthesis of sulfated agarose can provide sulfur contents of up to 14.6 wt% in it. The incorporation of a sulfate group into the agarose molecule has been confirmed by elemental analysis and Fourier-transform infrared spectroscopy: the absorption bands at 1249 cm‒1 have been observed in the spectra. The X-ray diffraction and atomic force microscopy studies have revealed no ammonium sulfamate inclusions. According to the X-ray diffraction patterns, sulfation of agarose enhances its X-ray amorphism. It has been established from the atomic force microscopy images that the incorporation of a sulfate group into the agarose molecule changes the size of particles on the film surface from 42 to 80 nm. The theoretical examination of initial and sulfated agarose has been carried out within the density functional theory. The molecular geometry, vibration assignments, HOMO‒LUMO, molecular electrostatic potential maps, and electronic properties of the substances have been established by the quantum-chemical calculations in the framework of the density functional theory.

Synthesis, spectral, antifungal, in silico molecular docking, ADME and DFT studies of some 2-(2-hydrazineyl)thiazole derivatives: Computational and experimental perspective

A series of thiazole Schiff bases (4a-4q) is synthesized and evaluated for the antibiofilm potential against fungal species C. albicans. The compounds 4a, 4b, 4c, 4p and 4q showed significant antibiofilm activity. Compounds 4a, 4b and 4c showed antibiofilm activities at 100 µg/mL concentrations, whereas 4p, and 4q showed activities around 50 µg/mL concentrations. Microscope study also supports the antibiofilm activity of compounds 4a,4b,4c, 4p and 4q. Molecular mechanism of action of bioactive derivatives for antibiofilm activities was studied by analysing the expression levels of some genes involved in the biofilm formations via qPCR. The molecular docking simulations with CYP51 revealed these compounds interact via hydrophobic and Van der Waals binding. The MESP surfaces were plotted using DFT method which also supported the molecular docking interactions.The ADME profile of these compounds revealed favourable pharmacological characteristics.

Cu(II)-mediated annulation of 4-hydroxycoumarins with propargyl carbonates: Facile access to furo[3,2-c]coumarin scaffold

An efficient and facile approach to furo[3,2-c]coumarin was developed from 4-hydroxycoumarins and propargyl carbonates. This protocol underwent [3 + 2] annulation process smoothly under mild reaction conditions to afford the desired products in moderate to excellent yields. A plausible mechanism was proposed. The products obtained could be readily converted into potentially bioactive furocoumarin derivatives.

TD-DFT, DFT, docking, MD simulations, and concentration-dependent SERS investigations of a bioactive trifluoromethyl derivative having human acetylcholinesterase and butyrylcholinesterase in silver colloids.

Various concentrations of (E)-4-methoxy-N'-(2-(trifluoromethyl)benzylidene) benzohydrazide (EMT) adsorbed on colloidal silver nanoparticles were studied using SERS and results were compared to the normal Raman spectrum. DFT calculations were used to validate experimental findings. Theoretically, the structures of the EMT and EMT-Ag6 systems were optimized. The UV-Vis spectral analysis's red shift and lower intensity behavior show that EMT has chemisorbed onto Ag nanoparticles. Charge transfer (CT) from Ag to EMT is highlighted by FMO analysis. The CT interaction in EMT and EMT-Ag6 was further verified by MEP and Mulliken charge analyses. The EMT was adsorbed on Ag nanoparticles with tilted orientation and orientation changes with colloidal concentration, according to SERS spectrum analysis. Docking EMT with 4PQE and 5DYW binding affinities are found to be -9.7 and -8.1 kcal/mol. MD simulations give the competence of 5DYW-EMT and 4PQE-EMT in their intended binding interactions and their ability to establish enduring associations with the protein of interest. DFT was used to optimize the molecular structures of EMT and EMT-Ag6 using B3LYP/6-311++G* (LANL2DZ basis set for Ag). A molecular dynamics simulation study was conducted on the 4PQE-EMT and 5DYW-EMT systems using the Desmond software for 100 ns.

Microwave-assisted Synthesis of Pharmacologically Active 4-Phenoxyquinolines and their Benzazole-quinoline Hybrids Through SNAr Reaction of 4,7-dichloroquinoline and Phenols Using [bmim][PF6] as a Green Solvent.

Quinoline and its derivatives have been shown to display a wide spectrum of biological properties, especially anticancer activity. Particularly, diverse potent anticancer drugs are based on the 4-phenoxyquinoline skeleton, acting as small-molecules VEGR2 and/or c-Met kinase inhibitors. However, the design of new drugs based on these quinoline derivatives remains a challenge. Up till now, all approaches to 4-phenoxyquinoline skeleton construction do not obey any green chemistry principles. Developing a new, and efficient protocol for the synthesis of potentially bioactive 4-phenoxyquinoline derivatives and benzazole-quinoline-quinoline hybrids from commercially available 4,7-dichloroquinoline and phenol derivatives using microwave energy (MW) in the presence of 1-methyl 3-butylimidazolium hexafluorophosphate. Neweco-efficient protocol for valuable 7-chloro-4-phenoxyquinolines and their hybrids, which is based on SNAr reaction of 4,7-dichloroquinoline with respective simple phenols and hydroxyaryl- benzazoles under MWenergy in green reaction media, is studied for the first time. We found that among various solvents tested, the ionic liquid 1-methyl 3-butylimidazolium hexafluorophosphate ([bmim][PF6]) favored the SNAr reaction affording phenoxyquinolines in excellent yields (72-82%) in 10 min. The developed protocol allowed to obtain quickly in good yields (48-60%) new diverse benzazole-quinoline hybrids, which are expected to be pharmacologically active. According to the calculated bioactivity scores, new hybrids are potential kinase inhibitors that could be useful in anticancer drug research. We developed for the first time a new green, efficient method to prepare potentially bioactive functionalized 7-chloro-4-phenoxyquinolines and benzazole-quinoline molecules. Good to excellent yields of the quinoline products, use of MW irradiation in ([bmim] [PF6] as a green solvent, and short times of reactions are some of the main advantages of this new protocol.

Oxetane Synthesis via Alcohol C-H Functionalization.

Oxetanes are strained heterocycles with unique properties that have triggered significant advances in medicinal chemistry. However, their synthesis still presents significant challenges that limit the use of this class of compounds in practical applications. In this Letter, we present a methodology that introduces a new synthetic disconnection to access oxetanes from native alcohol substrates. The generality of the approach is demonstrated by the application in late-stage functionalization chemistry, which is further exploited to develop a single-step synthesis of a known bioactive synthetic steroid derivative that previously required at least four synthetic steps from available precursors.

Insights into the Adsorption Nature of a Bioactive Anticancer Derivative of Benzenesulfonate on Silver Colloids at Various Concentrations: Experimental and DFT Investigations

Density functional theory was used in the present study to report and validate the 4-chloro-2-[(3,5-dichlorophenyl)carbamoyl]phenylbenzenesulfonate’s (CPB) IR, Raman and SERS spectra. The molecular systems, CPB and CPB-Ag6 were initially optimized. Frontier molecular orbital study demonstrates that in CPB-Ag6 complex, charge transfer (CT) interaction occurs between Ag and molecule. CT interaction in the examined systems was further verified by the MEP surface. The CPB is chemisorbed on Ag6 with affinity and a tilted orientation through lone pair electrons of atoms, according to Raman and SERS spectral analyses. Additionally, there was good correlation between the theoretical and observed results. The current study thus lays the path for designing robust SERS active substrates that will be useful for creating biosensors related to the CPB molecule.

Bioanalytical LC-QTOF/MS Method for a N-phenylpiperazine Derivate (LQFM05): An Anxiolytic- and Antidepressant-like Prototype Drug Applied to Pharmacokinetic and Biodistribution Studies.

The LQFM05 is a prototype drug designed for treatment of psychiatric disorders, such as schizophrenia, exhibiting anxiolytic- and antidepressant-like (12 or 24 µmol/kg) effects in classical behavioral tests. In order to evaluate its pharmacokinetic properties, a liquid chromatography method coupled to a quadrupole time of flight mass spectrometry system (LC-QTOF/MS) was developed and fully validated for LQFM05 analysis in rat plasma and tissue samples (brain, heart, liver, and kidneys). Liquid-liquid extraction, solid phase extraction and protein precipitation were assessed as clean-up procedures for biological samples and analyte enrichment. Plasma and tissue samples underwent protein precipitation as a preliminary step, using acetonitrile. Linearity was fully demonstrated for the dynamic range (10.0 to 900.0 ng/mL), with r2 values higher than 0.99 (RSDslope ≤ 2%, Fcal < Ftab, Ccal < Ctab). Biodistribution studies in rats revealed high brain tissue concentrations (12.4 µg/g), suggesting elevated drug affinity to the main therapeutic target tissue, showing a blood partition coefficient of 1.9. Kidneys also showed great exposure and tissue affinity, suggesting a potential extrahepatic clearance. Likewise, all examined tissues exhibited satisfactory LQFMF05 distribution. The mass fragmentation spectrum indicated the presence of its main metabolite, LQFM235, yielded by high hepatic hydroxylation route, an equally bioactive derivative. Lastly, the developed LC-QTOF/MS method was shown to be sensitive (LOQ = 10 ng/mL), precise and accurate for LQFM05 determination in tissue homogenates and plasma samples.

Medicinal importance and chemosensing applications of Schiff base derivatives for the detection of metal ions: A review

Schiff bases, named after Hugo Schiff, are formed when primary amine reacts with carbonyl compounds (aldehyde or ketone) under specific conditions. Schiff bases are economical, simple synthetic routes, and easily accessible in laboratories. They have medicinal and biological applications such as antiviral, antioxidant, antifungal, anticancer, anthelmintic, antibacterial, antimalarial, anti-inflammatory, antiglycation, anti-ulcerogenic, and analgesic potentials. A number of Schiff bases are reported for the detection of various metal ions. They are also used as catalysts, polymer stabilizers, intermediates in organic synthesis, and corrosion inhibitors. In this review, we have highlighted the recent advancements in the development of bioactive Schiff base derivatives and their sensing applications for detecting metal cations. Additionally, various spectroscopic techniques for structural characterization, such as X-ray diffraction analysis (XRD), FT-IR, UV-vis, and NMR spectroscopy were also discussed.

Adsorption behaviour on silver nanocolloids at various concentrations of a bioactive therapeutic derivative of methylhydrazine: Experimental, DFT and molecular docking investigations

A detailed theoretical and experimental study was implemented on a novel bioactive molecule 2-(3-bromobenzoyl)-N-methylhydrazine-1-carboxamide (BMC). Density Functional Theory (DFT), Time Dependent (TD)-DFT and Surface Enhanced Raman Scattering (SERS) studies were reported for the adsorption of BMC on silver hydrosols. SERS at various concentrations are discussed and there are orientation changes for BMC with concentration and BMC assumes a tilted orientation with the metal. The adsorption energy of BMC is −64.41 kcal/mol when adsorbed with Ag6, pointing to a chemisorption process. TD-DFT predicts a Ultraviolet (UV)-vis absorption of 595.11 when BMC adsorbed on Ag6, while that of BMC is 276.12 nm and the redshift, lowered intensity in UV spectra, caused by the aggregation of colloidal silver nano particles, was used to establish the adsorption of BMC on Ag6. Molecular docking is performed on BMC and BMC-Ag6 to find their ability to bind to target proteins, IP0I (human butyrylcholinesterase) and 4PQE (human acetylcholinesterase) and drug likeness properties are also assessed. The binding scores are high for BMC-Ag6 and hence the Ag6 will perform as a drug delivery vehicle.

Three-component p-TSA catalyzed synthesis of hydrazinyl thiazole derivatives

A direct single-pot three-component procedure for synthesizing bio-active hydrazinyl thiazole derivatives has been demonstrated. The reaction involves substituted 2-Bromoacetophenones, carboxaldehydes, and thiosemicarbazide to form the hydrazinyl thiazole scaffolds via a simple condensation reaction followed by intramolecular cyclization with p-TSA as a catalyst at room temperature. The ease of product separation, lack of column chromatographic purification, and use of readily available starting materials result in an efficient approach for organic synthesis.

Nutrients, herbal bioactive derivatives and commensal microbiota as tools to lower the risk of SARS-CoV-2 infection.

The SARS-CoV-2 outbreak has infected a vast population across the world, causing more than 664 million cases and 6.7 million deaths by January 2023. Vaccination has been effective in reducing the most critical aftermath of this infection, but some issues are still present regarding re-infection prevention, effectiveness against variants, vaccine hesitancy and worldwide accessibility. Moreover, although several old and new antiviral drugs have been tested, we still lack robust and specific treatment modalities. It appears of utmost importance, facing this continuously growing pandemic, to focus on alternative practices grounded on firm scientific bases. In this article, we aim to outline a rigorous scientific background and propose complementary nutritional tools useful toward containment, and ultimately control, of SARS-CoV-2 infection. In particular, we review the mechanisms of viral entry and discuss the role of polyunsaturated fatty acids derived from α-linolenic acid and other nutrients in preventing the interaction of SARS-CoV-2 with its entry gateways. In a similar way, we analyze in detail the role of herbal-derived pharmacological compounds and specific microbial strains or microbial-derived polypeptides in the prevention of SARS-CoV-2 entry. In addition, we highlight the role of probiotics, nutrients and herbal-derived compounds in stimulating the immunity response.

Metabolic Degradation and Bioactive Derivative Synthesis of Phenazine-1-Carboxylic Acid by Genetically Engineered Pseudomonas chlororaphis HT66

Phenazine-1-carboxylic acid (PCA) secreted by Pseudomonas chlororaphis has been commercialized and widely employed as an antifungal pesticide. However, it displays potential hazards to nontarget microorganisms and the environment. Although the PCA degradation characteristics have received extensive attention, the biodegradation efficiency is still insufficient to address the environmental risks. In this study, an engineered Pseudomonas capable of degrading PCA was constructed by introducing heterologous PCA 1,2-dioxygenase (PcaA1A2A3A4). By integrating the PCA degradation module in the chemical mutagenesis mutant P3, 7.94 g/L PCA can be degraded in 60 h, which exhibited the highest PCA degradation efficiency to date and was 35.4-fold higher than that of the PCA natural degraders. Additionally, PCA was converted to 1-methoxyphenazine through structure modification by introducing the functional enzymes PhzSPa and PhzMLa, which has good antifungal activity and environmental compatibility. This work demonstrates new possibilities for developing PCA-derived biopesticides and enables targeted control of the impact of PCA in diverse environments.

Bioactive Xanthone C-glycoside Derivatives – QSAR Approach

Introduction. Xanthone glycosides have unique structures and properties. Many efforts focus on the search for C-glycoside derivatives of mangiferin with higher bioavailability. The application of the QSAR approach allows for the optimization of the search for novel xanthone derivatives with the desired characteristics.Aim. Using available descriptors of chemical structure, physical-chemical properties, and biological activity, analyze a sample set of known homologs and analogs of mangiferin to QSAR prognosis bioactivity of new xanthone C-glycosides.Materials and methods. 26 molecules of natural homologs and modified derivatives of mangiferin formed the analyzed sample set. Topological graphs of compounds were constructed using ChemicPen software. ChemicDescript software was used for the calculation of molecular descriptors, including the Balaban index. Physicochemical characteristics of molecules as well as Lipinski's rule criteria were calculated in Molinspiration. The spectrum of the most probable (Pa &gt; 0.7) biological activity of the described compounds were predicted using Pass Online. The software Origin (OriginLab, USA) was used for the graphical representation of the results.Results and discussion. Mangiferin and its natural homologs are the most hydrophilic compounds. The hydrolysis of the C-glycosidic bond, alkylation, acylation, and the introduction of an amino substituent radical into the mangiferin structure led to the increase of its lipophilic properties. The spectrum of the most probable biological activities of the described molecules: antitumor, antioxidant, and cardioprotective effects. The results of ADMET modeling based on the substance-drug similarity criteria showed that only 4 compounds correspond to the rule of five. We proposed the validation model to predict bioactivity from lipophilicity and molecule structure described with Balaban index. The error of prediction obtained in a result of cross-validation turned out to be about less than 3 %.Conclusion. A correlation between the structure and properties of the molecules discussed has been demonstrated. The obtained results can be used for further prediction of the properties of natural and synthetic xanthone C-glycosides and directed synthesis of new active compounds.