Selective Removal of Chlorophyll and Isolation of Lutein from Plant Extracts Using Magnetic Solid Phase Extraction with Iron Oxide Nanoparticles.

In recent years, there has been a growing interest in plant pigments as readily available nutraceuticals. Photosynthetic pigments, specifically chlorophylls and carotenoids, renowned for their non-toxic antioxidant properties, are increasingly finding applications beyond their health-promoting attributes. Consequently, there is an ongoing need for cost-effective methods of isolation. This study employs a co-precipitation method to synthesize magnetic iron oxide nanoparticles. Scanning electron microscopy (SEM) coupled with energy dispersive spectrometry (EDS) confirms that an aqueous environment and oxidizing conditions yield nanosized iron oxide with particle sizes ranging from 80 to 140 nm. X-ray photoelectron spectroscopy (XPS) spectra indicate the presence of hydrous iron oxide FeO(OH) on the surface of the nanosized iron oxide. The Brunauer-Emmett-Teller (BET) surface area of obtained nanomaterial was 151.4 m2 g-1, with total pore volumes of pores 0.25 cm3 g-1 STP. The material, designated as iron oxide nanoparticles (IONPs), serves as an adsorbent for magnetic solid phase extraction (MSPE) and isolation of photosynthetic pigments (chlorophyll a, lutein) from extracts of higher green plants (Mentha piperita L., Urtica dioica L.). Sorption of chlorophyll a onto the nanoparticles is confirmed using UV-vis spectroscopy, Fourier transform infrared photoacoustic spectroscopy (FT-IR/PAS), and high-performance liquid chromatography (HPLC). Selective sorption of chlorophyll a requires a minimum of 3 g of IONPs per 12 mg of chlorophyll a, with acetone as the solvent, and is dependent on a storage time of 48 h. Extended contact time of IONPs with the acetone extract, i.e., 72 h, ensures the elimination of remaining components except lutein, with a spectral purity of 98%, recovered with over 90% efficiency. The mechanism of chlorophyll removal using IONPs relies on the interaction of the pigment's carbonyl (C=O) groups with the adsorbent surface hydroxyl (-OH) groups. Based on molecular dynamics (MD) simulations, it has been proven that the selective adsorption of pigments is also influenced by more favorable dispersion interactions between acetone and chlorophyll in comparison with other solutes. An aqueous environment significantly promotes the removal of pigments; however, it results in a complete loss of selectivity.

Conformational flexibility of the disaccharide ß-L-Fucp-(1→4)-α-D-Glcp-OMe as deduced from NMR spectroscopy experiments and computer simulations.

Carbohydrates in biological systems are referred to as glycans and modification of their structures is a hallmark indicator of disease. Analysis of the three-dimensional structure forms the basis for further insight into how they function and comparison of crystal structure with solution-state conformation(s) is particularly relevant, which has been performed for the disaccharide ß-L-Fucp-(1→4)-α-D-Glcp-OMe. In water solution the conformational space at the glycosidic linkage between the two sugar residues is identified from molecular dynamics (MD) simulations as having a low-energy exo-syn conformation, deviating somewhat from the solid-state conformation, and two anti-conformational states, i.e., anti-ϕ and anti-ψ, indicating flexibility at the glycosidic linkage. NMR data were obtained from 1D 1H,1H-NOESY and STEP-NOESY experiments, measurement of transglycosidic 3JCH coupling constants and NMR spin-simulation. The free energy profile of the ω torsion angle computed from MD simulation was in excellent agreement with the rotamer distribution from NMR experiment being for gt:gg:tg 38 : 53 : 9, respectively, with a proposed inter-residue O5'⋯HO6 hydrogen bond being predominant in the gg rotamer. Quantum mechanics methodology was used to calculate transglycosidic NMR 3JCH coupling constants, averaged over a conformational ensemble of structures representing various rotamers of exocyclic groups, in good to excellent agreement with Karplus-type relationships previously developed. Furthermore, 1H and 13C NMR chemical shifts were calculated using the same methodology and were found to be in excellent agreement with experimental data.

Thalidomide derivatives as nanomolar human neutrophil elastase inhibitors: Rational design, synthesis, antiproliferative activity and mechanism of action.

Here, we rationally designed a human neutrophil elastase (HNE) inhibitors 4a-4f derived from thalidomide. The HNE inhibition assay showed that synthesized compounds 4a, 4b, 4e and 4f demonstrated strong HNE inhibiton properties with IC50 values of 21.78-42.30 nM. Compounds 4a, 4c, 4d and 4f showed a competitive mode of action. The most potent compound 4f shows almost the same HNE inhibition as sivelestat. The molecular docking analysis revealed that the strongest interactions occur between the azetidine-2,4-dione group and the following three aminoacids: Ser195, Arg217 and His57. A high correlation between the binding energies and the experimentally determined IC50 values was also demonstrated. The study of antiproliferative activity against human T47D (breast carcinoma), RPMI 8226 (multiple myeloma), and A549 (non-small-cell lung carcinoma) revealed that designed compounds were more active compared to thalidomide, pomalidomide and lenalidomide used as the standard drugs. Additionally, the most active compound 4f derived from lenalidomide induces cell cycle arrest at the G2/M phase and apoptosis in T47D cells.

Identification of the first-in-class dual inhibitors of human DNA topoisomerase IIα and indoleamine-2,3-dioxygenase 1 (IDO 1) with strong anticancer properties.

Molecular docking of a large set of thiosemicarbazide-based ligands resulted in obtaining compounds that inhibited both human DNA topoisomerase IIα and indoleamine-2,3-dioxygenase-1 (IDO1). To the best of our knowledge, these compounds are the first dual inhibitors targeting these two enzymes. As both of them participate in the anticancer response, the effect of the compounds on a panel of cancer cell lines was examined. Among the cell lines tested, lung cancer (A549) and melanoma (A375) cells were the most sensitive to compounds 1 (IC50=0.23 µg/ml), 2 (IC50=0.83 µg/ml) and 3 (IC50=0.25 µg/ml). The observed activity was even 90-fold higher than that of etoposide, with selectivity index values reaching 125. In-silico simulations showed that contact between 1-3 and human DNA topoisomerase II was maintained through aromatic moieties located at limiting edges of ligand molecules and intensive interactions of the thiosemicarbazide core with the DNA fragments present in the catalytic site of the enzyme.

Synthesis of Novel 2-(Cyclopentylamino)thiazol-4(5H)-one Derivatives with Potential Anticancer, Antioxidant, and 11ß-HSD Inhibitory Activities.

In this study, a series of nine new 2-(cyclopentylamino)thiazol-4(5H)-one derivatives were synthesized, and their anticancer, antioxidant, and 11ß-hydroxysteroid dehydrogenase (11ß-HSD) inhibitory activities were tested. Anticancer activity has been assessed using the MTS (MTS: 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assay against human colon carcinoma (Caco-2), human pancreatic carcinoma (PANC-1), glioma (U-118 MG), human breast carcinoma (MDA-MB-231), and skin melanoma (SK-MEL-30) cancer cell lines. Cell viability reductions, especially in the case of Caco-2, MDA-MB-231, and SK-MEL-30 lines, were observed for most compounds. In addition, the redox status was investigated and oxidative, but nitrosative stress was not noted at a concentration of 500 µM compounds tested. At the same time, a low level of reduced glutathione was observed in all cell lines when treated with compound 3g (5-(4-bromophenyl)-2-(cyclopentylamino)thiazol-4(5H)-one) that most inhibited tumor cell proliferation. However, the most interesting results were obtained in the study of inhibitory activity towards two 11ß-HSD isoforms. Many compounds at a concentration of 10 µM showed significant inhibitory activity against 11ß-HSD1 (11ß-hydroxysteroid dehydrogenase type 1). The compound 3h (2-(cyclopentylamino)-1-thia-3-azaspiro[4.5]dec-2-en-4-one) showed the strongest 11ß-HSD1 inhibitory effect (IC50 = 0.07 µM) and was more selective than carbenoxolone. Therefore, it was selected as a candidate for further research.

Significance of Astragaloside IV from the Roots of Astragalus mongholicus as an Acetylcholinesterase Inhibitor-From the Computational and Biomimetic Analyses to the In Vitro and In Vivo Studies of Safety.

The main aim of the study was to assess the acetylcholinesterase-inhibitory potential of triterpenoid saponins (astragalosides) found in the roots of Astragalus mongholicus. For this purpose, the TLC bioautography method was applied and then the IC50 values were calculated for astragalosides II, III and IV (5.9 µM; 4.2 µM, and 4.0 µM, respectively). Moreover, molecular dynamics simulations were carried outto assess the affinity of the tested compounds for POPC and POPG-containing lipid bilayers, which in this case are the models of the blood-brain barrier (BBB). All determined free energy profiles confirmed that astragalosides exhibit great affinity for the lipid bilayer. A good correlation was obtained when comparing the logarithm of n-octanol/water partition coefficient (logPow) lipophilicity descriptor values with the smallest values of free energy of the determined 1D profiles. The affinity for the lipid bilayers changes in the same order as the corresponding logPow values, i.e.,: I > II > III~IV. All compounds exhibit a high and also relatively similar magnitude of binding energies, varying from ca. -55 to -51 kJ/mol. Apositive correlation between the experimentally-determined IC50 values and the theoretically-predicted binding energies expressed by the correlation coefficient value equal 0.956 was observed.

Interaction of Chondroitin and Hyaluronan Glycosaminoglycans with Surfaces of Carboxylated Carbon Nanotubes Studied Using Molecular Dynamics Simulations.

Interaction of ß-D-glucopyranuronic acid (GlcA), N-acetyl-ß-D-glucosamine (GlcNAc), N-acetyl-ß-D-galactosamine (GalNAc) and two natural decameric glycosaminoglycans, hyaluronic acid (HA) and Chondroitin (Ch) with carboxylated carbon nanotubes, were studied using molecular dynamics simulations in a condensed phase. The force field used for carbohydrates was the GLYCAM-06j version, while functionalized carbon nanotubes (fCNT) were described using version two of the general amber force field. We found a series of significant differences in carbohydrate-fCNT adsorption strength depending on the monosaccharide molecule and protonation state of surface carboxyl groups. GlcNAc and GalNAc reveal a strong adsorption on fCNT with deprotonated carboxyl groups, and a slightly weaker adsorption on the fCNT with protonated carboxyl groups. On the contrary, GlcA weakly adsorbs on fCNT. The change in protonation state of surface carboxyl groups leads to the reversal orientation of GlcNAc and GalNAc in reference to the fCNT surface, while GlcA is not sensitive to that factor. Adsorption of decameric oligomers on the surface of fCNT weakens with the increasing number of monosaccharide units. Chondroitin adsorbs weaker than hyaluronic acid and incorporation of four Ch molecules leads to partial detachment of them from the fCNT surface. The glycan-fCNT interactions are strong enough to alter the conformation of carbohydrate backbone; the corresponding conformational changes act toward a more intensive contact of glycan with the fCNT surface. Structural and energetic features of the adsorption process suggest the CH-π interaction-driven mechanism.

The Val34Met, Thr164Ile and Ser220Cys Polymorphisms of the ß2-Adrenergic Receptor and Their Consequences on the Receptor Conformational Features: A Molecular Dynamics Simulation Study.

The gene encoding the ß2-adrenergic receptor (ß2-AR) is polymorphic, which results in possible differences in a primary structure of this protein. It has been shown that certain types of polymorphisms are correlated with some clinical features of asthma, including airways reactivity, whereas the influence of other is not yet understood. Among polymorphisms affecting amino acids at positions 16, 27, 34, 164 and 220, the latter three are present in the crystal structure of ß2-AR, which facilitates studying them by means of molecular dynamics simulations. The current study was focused on investigating to what extent the three polymorphisms of ß2-AR (i.e., Val34Met, Thr164Ile and Ser220Cys) affect the interaction of ß2-AR with its natural molecular environment which includes: lipid bilayer (in the case of all three polymorphs) and Gs protein (which participates in ß2-AR-mediated signaling; in the case of Ser220Cys). We have designed and carried out a series of molecular dynamics simulations at different level of resolution (i.e., either coarse-grained or atomistic simulations), accompanied by thermodynamic integration protocol, in order to identify potential polymorphism-induced alterations in structural, conformational or energetic features of ß2-AR. The results indicate the lack of significant differences in the case of energies involved in the ß2-AR-lipid bilayer interactions. Some differences have been observed when considering the polymorphism-induced alterations in ß2-AR-Gs protein binding, but their magnitude is also negligible in relation to the absolute free energy difference correlated with the ß2-AR-Gs affinity. The Val34Met and Thr164Ile polymorphisms are weakly correlated with alteration of the conformational features of the receptor around polymorphic sites. On the contrary, it has been concluded that the Ser220Cys polymorphism is correlated with several structural alterations located in the intracellular region of ß2-AR, which can induce G-protein binding and, subsequently, the polymorphism-correlated therapeutic responses. More precisely, these alterations involve vicinity of intracellular loops and, in part, are the direct consequence of disturbed interactions of Ser/Cys220 sidechain within 5th transmembrane domain. Structurally, the dynamic structure exhibited by the ß2-ARSer220 polymorph is closer to the Gs-compatible structure of ß2-AR.

Spectrofluorimetric and Computational Investigation of New Phthalimide Derivatives towards Human Neutrophil Elastase Inhibition and Antiproliferative Activity.

Herein, nine phthalimide-based thiazoles (4a-4i) were synthesized and investigated as new human neutrophil elastase (HNE) inhibitors using spectrofluorimetric and computational methods. The most active compounds containing 4-trifluoromethyl (4c), 4-naphthyl (4e) and 2,4,6-trichloro (4h) substituents in the phenyl ring exhibited high HNE inhibitory activity with IC50 values of 12.98-16.62 µM. Additionally, compound 4c exhibited mixed mechanism of action. Computational investigation provided a consistent picture of the ligand-receptor pattern of inter-actions, common for the whole considered group of compounds. Moreover, compounds 4b, 4c, 4d and 4f showed high antiproliferative activity against human cancer cells lines MV4-11, and A549 with IC50 values of 8.21 to 25.57 µM. Additionally, compound 4g showed high activity against MDA-MB-231 and UMUC-3 with IC50 values of 9.66 and 19.81 µM, respectively. Spectrophotometric analysis showed that the most active compound 4c demonstrated high stability under physiological conditions.

Discovery of New 3,3-Diethylazetidine-2,4-dione Based Thiazoles as Nanomolar Human Neutrophil Elastase Inhibitors with Broad-Spectrum Antiproliferative Activity.

A series of 3,3-diethylazetidine-2,4-dione based thiazoles 3a-3j were designed and synthesized as new human neutrophil elastase (HNE) inhibitors in nanomolar range. The representative compounds 3c, 3e, and 3h exhibit high HNE inhibitory activity with IC50 values of 35.02-44.59 nM, with mixed mechanism of action. Additionally, the most active compounds 3c and 3e demonstrate high stability under physiological conditions. The molecular docking study showed good correlation of the binding energies with the IC50 values, suggesting that the inhibition properties are largely dependent on the stage of ligand alignment in the binding cavity. The inhibition properties are correlated with the energy level of substrates of the reaction of ligand with Ser195. Moreover, most compounds showed high and broad-spectrum antiproliferative activity against human leukemia (MV4-11), human lung carcinoma (A549), human breast adenocarcinoma (MDA-MB-231), and urinary bladder carcinoma (UMUC-3), with IC50 values of 4.59-9.86 µM. Additionally, compounds 3c and 3e can induce cell cycle arrest at the G2/M phase and apoptosis via caspase-3 activation, leading to inhibition of A549 cell proliferation. These findings suggest that these new types of drugs could be used to treat cancer and other diseases in which immunoreactive HNE is produced.

Amorphous Inclusion Complexes: Molecular Interactions of Hesperidin and Hesperetin with HP-Β-CD and Their Biological Effects.

This study aimed at obtaining hesperidin (Hed) and hesperetin (Het) systems with HP-ß-CD by means of the solvent evaporation method. The produced systems were identified using infrared spectroscopy (FT-IR), X-ray powder diffraction (XRPD), and differential scanning calorimetry (DSC). Moreover, in silico docking and molecular dynamics studies were performed to assess the most preferable site of interactions between tested compounds and HP-ß-CD. The changes of physicochemical properties (solubility, dissolution rate, and permeability) were determined chromatographically. The impact of modification on biological activity was tested in an antioxidant study as well as with regards to inhibition of enzymes important in pathogenesis of neurodegenerative diseases. The results indicated improvement in solubility over 1000 and 2000 times for Hed and Het, respectively. Permeability studies revealed that Hed has difficulties in crossing biological membranes, in contrast with Het, which can be considered to be well absorbed. The improved physicochemical properties influenced the biological activity in a positive manner by the increase in inhibitory activity on the DPPH radical and cholinoesterases. To conclude the use of HP-ß-CD as a carrier in the formation of an amorphous inclusion complex seems to be a promising approach to improve the biological activity and bioavailability of Hed and Het.

The Distribution of Glucosinolates in Different Phenotypes of Lepidium peruvianum and Their Role as Acetyl- and Butyrylcholinesterase Inhibitors-In Silico and In Vitro Studies.

The aim of the study was to present the fingerprint of different Lepidium peruvianum tuber extracts showing glucosinolates-containing substances possibly playing an important role in preventinting dementia and other memory disorders. Different phenotypes of Lepidium peruvianum (Brassicaceae) tubers were analysed for their glucosinolate profile using a liquid chromatograph coupled with mass spectrometer (HPLC-ESI-QTOF-MS/MS platform). Qualitative analysis in 50% ethanolic extracts confirmed the presence of ten compounds: aliphatic, indolyl, and aromatic glucosinolates, with glucotropaeolin being the leading one, detected at levels between 0-1.57% depending on phenotype, size, processing, and collection site. The PCA analysis showed important variations in glucosinolate content between the samples and different ratios of the detected compounds. Applied in vitro activity tests confirmed inhibitory properties of extracts and single glucosinolates against acetylcholinesterase (AChE) (15.3-28.9% for the extracts and 55.95-57.60% for individual compounds) and butyrylcholinesterase (BuChE) (71.3-77.2% for the extracts and 36.2-39.9% for individual compounds). The molecular basis for the activity of glucosinolates was explained through molecular docking studies showing that the tested metabolites interacted with tryptophan and histidine residues of the enzymes, most likely blocking their active catalytic side. Based on the obtained results and described mechanism of action, it could be concluded that glucosinolates exhibit inhibitory properties against two cholinesterases present in the synaptic cleft, which indicates that selected phenotypes of L. peruvianum tubers cultivated under well-defined environmental and ecological conditions may present a valuable plant material to be considered for the development of therapeutic products with memory-stimulating properties.

New Borane-Protected Derivatives of α-Aminophosphonous Acid as Anti-Osteosarcoma Agents: ADME Analysis and Molecular Modeling, In Vitro Studies on Anti-Cancer Activities, and NEP Inhibition as a Possible Mechanism of Anti-Proliferative Activity.

Many organophosphorus compounds (OPs), especially various α-aminophosphonates, exhibit anti-cancer activities. They act, among others, as inhibitors of the proteases implicated in cancerogenesis. Thesetypes of inhibitors weredescribed, e.g., for neutral endopeptidase (NEP) expressed in different cancer cells, including osteosarcoma (OS). The aim of the present study isto evaluate new borane-protected derivatives of phosphonous acid (compounds 1-7) in terms of their drug-likeness properties, anti-osteosarcoma activities in vitro (against HOS and Saos-2 cells), and use as potential NEP inhibitors. The results revealed that all tested compounds exhibited the physicochemical and ADME properties typical for small-molecule drugs. However, compound 4 did not show capability of blood-brain barrier penetration (Lipinski and Veber rules;SwissAdme tool). Moreover, the α-aminophosphonite-boranes (compounds 4-7) exhibited stronger anti-proliferative activity against OS cells than the other phosphonous acid-borane derivatives (compounds 1-3),especially regarding HOS cells (MTT assay). The most promising compounds 4 and 6 induced apoptosis through the activation of caspase 3 and/or cell cycle arrest at the G2 phase (flow cytometry). Compound 4 inhibited the migration and invasiveness of highly aggressive HOS cells (wound/transwell and BME-coated transwell assays, respectively). Additionally, compound 4 and, to a lesser extent, compound 6 inhibited NEP activity (fluorometric assay). This activity of compound 4 was involved in its anti-proliferative potential (BrdU assay). The present study shows that compound 4 can be considered a potential anti-osteosarcoma agent and a scaffold for the development of new NEP inhibitors.

The Systems of Naringenin with Solubilizers Expand Its Capability to Prevent Neurodegenerative Diseases.

BACKGROUND: Naringenin (NAR) is a flavonoid with excellent antioxidant and neuroprotective potential that is limited by its low solubility. Thus, solid dispersions with ß-cyclodextrin (ß-CD), hydroxypropyl-ß-cyclodextrin (HP-ß-CD), hydroxypropylmethylcellulose (HPMC), and microenvironmental pH modifiers were prepared. METHODS: The systems formation analysis was performed by X-Ray Powder Diffraction (XRPD) and Fourier-transform infrared spectroscopy (FT-IR). Water solubility and dissolution rates were studied with a pH of 1.2 and 6.8. In vitro permeability through the gastrointestinal tract (GIT) and the blood-brain barrier (BBB) was assessed with the parallel artificial membrane permeability assay (PAMPA) assay. The antioxidant activity was studied with the 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and cupric ion reducing antioxidant capacity (CUPRAC) assays, while in vitro enzymes studies involved the inhibition of acetylcholinesterase, butyrylcholinesterase, and tyrosinase. For the most promising system, in silico studies were conducted. RESULTS: NAR solubility was increased 458-fold by the solid dispersion NAR:HP-ß-CD:NaHCO3 in a mass ratio of 1:3:1. The dissolution rate was elevated from 8.216% to 88.712% in a pH of 1.2 and from 11.644% to 88.843% in a pH of 6.8 (within 3 h). NAR GIT permeability, described as the apparent permeability coefficient, was increased from 2.789 × 10-6 cm s-1 to 2.909 × 10-5 cm s-1 in an acidic pH and from 1.197 × 10-6 cm s-1 to 2.145 × 10-5 cm s-1 in a basic pH. NAR BBB permeability was established as 4.275 × 10-6 cm s-1. The antioxidant activity and enzyme inhibition were also increased. Computational studies confirmed NAR:HP-ß-CD inclusion complex formation. CONCLUSIONS: A significant improvement in NAR solubility was associated with an increase in its biological activity.

Influence of Selective Extraction/Isolation of Heme/Hemoglobin with Hydrophobic Imidazolium Ionic Liquids on the Precision and Accuracy of Cotinine ELISA Test.

In this study, ionic liquids were used for the selective extraction/isolation of hemoglobin from human serum for cotinine determination using the ELISA Kit. The suitability of hydrophobic imidazolium-based ionic liquids was tested, of which OMIM BF4 (1-methyl-3-octylimidazolium tetrafluoroborate) turned out to be the most suitable for direct extraction of hemoglobin into an ionic liquid without the use of any additional reagent at one extraction step. Hemoglobin was separated quantitatively (95% recovery) from the remaining types of proteins remaining in the aqueous phase. Quantum mechanical calculations showed that the interaction of the iron atom in the heme group and the nitrogen atom of the ionic liquid cation is responsible for the transfer of hemoglobin whereas molecular dynamics simulations demonstrated that the non-covalent interactions between heme and solvent are more favorable in the case of OMIM BF4 in comparison to water. The opposite trend was found for cotinine. Selective isolation of the heme/hemoglobin improved the ELISA test's accuracy, depending on the cotinine level, from 15% to 30%.

Tautomers of N-acetyl-d-allosamine: an NMR and computational chemistry study.

d-Allosamine is a rare sugar in Nature but its pyranoid form has been found α-linked in the core region of the lipopolysaccharide from the Gram-negative bacterium Porphyromonas gingivalis and in the chitanase inhibitor allosamidin, then ß-linked and N-acetylated. In water solution the monosaccharide N-acetyl-d-allosamine (d-AllNAc) shows a significant presence of four tautomers arising from pyranoid and furanoid ring forms and anomeric configurations. The furanoid ring forms both showed 3JH1,H2≈ 4.85 Hz and to differentiate the anomeric configurations a series of chemical shift anisotropy/dipole-dipole cross-correlated relaxation NMR experiments was performed in which the α-anomeric form showed notable different relaxation rates for its components of the H1 doublet, thereby making it possible to elucidate the anomeric configuration of each of the furanoses. The conformational preferences of the different forms of d-AllNAc were investigated by 3JHH, 2JCH and 3JCH coupling constants from NMR experiments, molecular dynamics simulations and density functional theory calculations. The pyranose form resides in the 4C1 conformation and the furanose ring form has the majority of its conformers located on the South-East region of the pseudorotation wheel, with a small population in the Northern hemisphere. The tautomeric equilibrium was quite sensitive to changes in temperature, where the ß-anomer of the pyranoid ring form decreased upon a temperature increase while the other forms increased.

Effect of the dichloro-substitution on antiproliferative activity of phthalimide-thiazole derivatives. Rational design, synthesis, elastase, caspase 3/7, and EGFR tyrosine kinase activity and molecular modeling study.

Phthalimide derivatives are a promising group of anticancer drugs, while aminothiazoles have great potential as elastase inhibitors. In these context fourteen phthalimido-thiazoles containing a dichloro-substituted phenyl ring with high antiproliferative activity against various cancer cell lines were designed and synthesized. Among the screened derivatives, compounds 5a-5e and 6a-6f showed high activity against human leukemia (MV4-11) cells with IC50 values in the range of 5.56-16.10 µM. The phthalimide-thiazoles 5a, 5b and 5d showed the highest selectivity index (SI) relative to MV4-11 with 11.92, 10.80 and 8.21 values, respectively. The antiproliferative activity of compounds 5e, 5f and 6e, 6f against human lung carcinoma (A549) cells is also very high, with IC50 values in the range of 6.69-10.41 µM. Lead compounds 6e and 6f showed elastase inhibition effect, with IC50 values about 32 µM with mixed mechanism of action. The molecular modeling studies showed that the binding energies calculated for all set of compounds are strongly correlated with the experimentally determined values of IC50. The lead compound 6e also increases almost 16 times caspase 3/7 activity in A549 cells compared to control. We have also demonstrated that compound 6f reduced EGFR tyrosine kinase levels in A549 cells by approximately 31%. These results clearly suggest that 3,4-dichloro-derivative 6e and 3,5-dichloro-derivative 6f could constitute lead dual-targeted anticancer drug candidates.

Molecular Structure of Cefuroxime Axetil Complexes with α-, ß-, γ-, and 2-Hydroxypropyl-ß-Cyclodextrins: Molecular Simulations and Raman Spectroscopic and Imaging Studies.

The formation of cefuroxime axetil+cyclodextrin (CA+CD) complexes increases the aqueous solubility of CA, improves its physico-chemical properties, and facilitates a biomembrane-mediated drug delivery process. In CD-based tablet formulations, it is crucial to investigate the molecular details of complexes in final pharmaceutical preparation. In this study, Raman spectroscopy and mapping were applied for the detection and identification of chemical groups involved in α-, ß-, γ-, and 2-hydroxypropyl-ß-CD (2-HP- ß-CD)+CA complexation process. The experimental studies have been complemented by molecular dynamics-based investigations, providing additional molecular details of CA+CD interactions. It has been demonstrated that CA forms the guest-host type inclusion complexes with all studied CDs; however, the nature of the interactions is slightly different. It seems that both α- and ß-CD interact with furanyl and methoxy moieties of CA, γ-CD forms a more diverse pattern of interactions with CA, which are not observed in other CDs, whereas 2HP-ß-CD binds CA with the contribution of hydrogen bonding. Apart from supporting this interpretation of the experimental data, molecular dynamics simulations allowed for ordering the CA+CD binding affinities. The obtained results proved that the molecular details of the host-guest complexation can be successfully predicted from the combination of Raman spectroscopy and molecular modeling.

Novel 2-(Adamantan-1-ylamino)Thiazol-4(5H)-One Derivatives and Their Inhibitory Activity towards 11ß-HSD1-Synthesis, Molecular Docking and In Vitro Studies.

A common mechanism in which glucocorticoids participate is suggested in the pathogenesis of such metabolic diseases as obesity, metabolic syndrome, or Cushing's syndrome. The enzyme involved in the control of the availability of cortisol, the active form of the glucocorticoid for the glucocorticoid receptor, is 11ß-HSD1. Inhibition of 11ß-HSD1 activity may bring beneficial results for the alleviation of the course of metabolic diseases such as metabolic syndrome, Cushing's syndrome or type 2 diabetes. In this work, we obtained 10 novel 2-(adamantan-1-ylamino)thiazol-4(5H)-one derivatives containing different substituents at C-5 of thiazole ring and tested their activity towards inhibition of two 11ß-HSD isoforms. For most of them, over 50% inhibition of 11ß-HSD1 and less than 45% inhibition of 11ß-HSD2 activity at the concentration of 10 µM was observed. The binding energies found during docking simulations for 11ß-HSD1 correctly reproduced the experimental IC50 values for analyzed compounds. The most active compound 2-(adamantan-1-ylamino)-1-thia-3-azaspiro[4.5]dec-2-en-4-one (3i) inhibits the activity of isoform 1 by 82.82%. This value is comparable to the known inhibitor-carbenoxolone. The IC50 value is twice the value determined by us for carbenoxolone, however inhibition of the enzyme isoform 2 to a lesser extent makes it an excellent material for further tests.

Combinations of Piperine with Hydroxypropyl-ß-Cyclodextrin as a Multifunctional System.

Piperine is an alkaloid that has extensive pharmacological activity and impacts other active substances bioavailability due to inhibition of CYP450 enzymes, stimulation of amino acid transporters and P-glycoprotein inhibition. Low solubility and the associated low bioavailability of piperine limit its potential. The combination of piperine with 2-hydroxypropyl-ß-cyclodextrin (HP-ß-CD) causes a significant increase in its solubility and, consequently, an increase in permeability through gastrointestinal tract membranes and the blood-brain barrier. X-ray powder diffraction (XRPD), differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (NMR) were used to characterize interactions between piperine and HP-ß-CD. The observed physicochemical changes should be combined with the process of piperine and CD system formation. Importantly, with an increase in solubility and permeability of piperine as a result of interaction with CD, it was proven to maintain its biological activity concerning the antioxidant potential (2,2-diphenyl-1-picryl-hydrazyl-hydrate assay), inhibition of enzymes essential for the inflammatory process and for neurodegenerative changes (hyaluronidase, acetylcholinesterase, butyrylcholinesterase).