With the aim to develop efficient synthetic routes to 7,8-substituted aryl-naphthalene lignans and structural analogs via a Photo-Dehydro-Diels-Alder reaction as key step, three different approaches were investigated. The first strategy is based on the presence of electron-withdrawing groups (EWG) as placeholder for alkoxy groups (EWG strategy). Although two lignan analogs ( 19 , 20 ) could be prepared the EWG strategy was not an optimum solution. The second strategy takes advantage of different sizes of meta -substituents to force the formation of 7,8-substituted products ( meta -directing strategy). Here, a sufficient large size difference is mandatory. While the combination TMS/OMe works very well and provided the access to natural product analogs 29 and 30 , the combination TMS/OBn completely failed. The third and most successful approach is based on blocking ortho -positions with the bulky TMS group ( ortho -blocking strategy). By using this method, the natural products helioxanthin 1 and retrohelioxanthin 2 could be successfully synthesized.

Three new phosphine Ni(II) complexes containing disulfido-2-(phenylsulfonyl)acrylonitrile ligand with compositions [Ni(dppe)(PSAN)] (Ni-dp), [Ni(dppf)(PSAN)] (Ni-df), and [Ni(PPh3)2(PSAN)] (Ni-PPh) (PSAN = 3,3disulfido-2-(phenylsulfonyl)acrylonitrile; dppe = 1,2-bis-(diphenylphosphinoethane) and dppf = 1,1 '-bis(diphenylphosphino)ferrocene) have been synthesized, characterized spectroscopically and by single crystal Xray diffraction technique. All three complexes show distorted square planar geometry around Ni(II), wherein Ni (II) is coordinated to two sulfur of PSAN ligand in bidentate chelating mode and two phosphorus centers of dppe, dppf and PPh3 ligands. All three complexes show intermolecular O & sdot;& sdot;& sdot;H-C and C-H & sdot;& sdot;& sdot;pi interactions, while Ni-dp and Ni-PPh additionally show intermolecular N & sdot;& sdot;& sdot;H-C interactions. Further, all three complexes show interesting intramolecular C-H & sdot;& sdot;& sdot;Ni anagostic interactions. The nature of these interactions have been investigated using Hirshfeld surface analyses and computational studies. The results indicate that crystal packing is dominated by CH & sdot;& sdot;& sdot;pi interactions held by dispersion forces, with the Ni-dp complex showing the highest overall stabilization. Anagostic C-H & sdot;& sdot;& sdot;Ni interactions are validated on the basis of their reduced C-H bond orders, low electron density at bond critical points and sigma(C-H) -> Ni(LP*) charge transfer.

Three new mononuclear complexes, including two cobalt(II) complexes, [Co(OH2)2(QPhF)2] 1 and [Co(OH2)2(QPhF)2]& centerdot;2DMF 2, along with one zinc(II) complex, [Zn(OH2)2(QPhF)2] 3, were synthesized from the reactions of 4-(4-fluorobenzoyl)-3-methyl-1-phenylpyrazol-5-one (HQPhF) with CoCl2 & centerdot;6H2O and Zn(NO3)2 & centerdot;6H2O at room temperature. These compounds were characterized by FT-IR and UV-visible spectroscopy, single-crystal X-ray diffraction and DFT studies. Crystallographic data showed that each compound crystallizes in a monoclinic system with 1 and 3 crystallizing in the same space group C2/c(15) with unit cell parameters a = 21.451(4) & Aring;, b = 10.790(2) & Aring;, c = 16.575(3) & Aring;, alpha = gamma = 90 degrees, beta = 128.90(3)degrees for 1 and a = 21.4553(9) & Aring;, b = 10.8147(3) & Aring;, c = 16.5330(7) & Aring;, alpha = gamma = 90 degrees, beta = 128.833(3)degrees for 3. 2 crystallizes in P 21/c with a = 12.8225(5) & Aring;, b = 15.5048(6) & Aring;, c = 10.0793(4) & Aring;, alpha = gamma = 90 degrees and beta = 109.977(5)degrees. In all structures, the metal centers adopt distorted octahedral geometries, built by four oxygen atoms from two QPhF- anions and two from H2O molecules. In compound 2, two DMF are present as lattice solvent molecules. The presence of intermolecular interactions (pi-pi stacking, hydrogen) and intermolecular strong hydrogen bonds (O-H & centerdot;& centerdot;& centerdot;F and O-H & centerdot;& centerdot;& centerdot;N) generates a 1D (compounds 1 and 3) or 2D (compound 2) supramolecular network. DFT studies reveal that changing the metal ion from Co(II) to Zn(II) decreases reactivity and increases the stability of 3.

Nine naturally occurring prenylated isoflavones and three nonnatural analogues were synthesized for the first time. The 12 newly synthesized and 11 previously synthesized isoflavones were tested for their activity as modulators of Saccharomyces cerevisiae α-glucosidase. Out of the 23 prenylated isoflavones tested in total, 4',7-dihydroxy-3',5'-diprenylisoflavone (26) and 8-prenyldaidzein (28), both secondary plant metabolites originally isolated from Psoralea corylifolia, were found to be the most potent inhibitors of S. cerevisiae α-glucosidase, with IC50 values of 7.8 ± 2.3 μM and 14.6 ± 5.1 μM, respectively. Kinetic analysis revealed that 26 acts through a noncompetitive mechanism and 28 through an uncompetitive mechanism of inhibition. Surprisingly, a few of the compounds tested, in particular isoflavones with a 6,7- and 3',4'-dioxy substitution pattern, were found to be activators of S. cerevisiae α-glucosidase. The most notable effects in this regard were observed for predurallone (21c), a secondary plant metabolite originally isolated from Millettia dura, and its nonnatural analogue 7-methylpredurallone (22c). At a concentration of 50 μM, both compounds enhanced the activity of S. cerevisiae α-glucosidase by 53.7 ± 8.8% and 41.5 ± 8.2%, respectively. To the best of our knowledge, these are the first examples of small molecule activators of this enzyme.

Piperine is a secondary metabolite derived from plants and fungi and exhibits a wide range of biological properties including antimicrobial, anticancer, anti-inflammatory, and antidiabetic activities. In the present study, the total synthesis of piperine (7a) and related analogues 7b-l was achieved starting from (E)-3,4-(methylenedioxy)-cinnamic acid (5) through PyBOP-mediated coupling with various amines 6. Seven of these analogues (compounds 7d, 7f-j and 7l) are hereby synthesized for the first time. Piperine (7a) displayed antifungal activity against Rhodotorula glutinis DSM-10134 (MIC value of 16.6 μg/mL) while piperic acid (5), piperine (7a), and its analogue 7d were active against the fungus Mucor hiemalis DSM2656 with MICs of 66.6, 33.3, and 33.3 μg/mL, respectively. Furthermore, the analogue 7d exhibited moderate activity against some cancer cell lines with IC50 values ranging from 7 to 21 μg/mL.

Ergosterol is the main sterol in yeast and an important lipid constituent of the yeast plasma membrane (PM). Methods for analysis of ergosterol trafficking between PM and subcellular compartments often rely on fluorescence microscopy, but existing sterol probes either mimic ergosterol poorly or have inconvenient fluorescence properties. Here, we present a novel intrinsically fluorescent probe that differs from ergosterol only by having a 3'-keto group and two additional conjugated double bonds in the ring system. We show that this analog, named Erg-Tetraene, can order fatty acyl chains of phospholipids and partitions partially into the liquid-ordered phase in model membranes containing cholesterol. The Erg-Tetraene has a red-shifted emission and a much stronger two-photon absorption than the widely used analog dehydroergosterol, allowing for its convenient imaging on commercial microscope systems. Using multi-color confocal and two-photon microscopy, we show that uptake of Erg-Tetraene into yeast depends on the sterol transporters Aus1/Pdr11 and is followed by rapid transport to the vacuole and to lipid droplets. Together, we present a novel analogue of ergosterol with improved fluorescence properties for sterol trafficking studies in yeast and other model organisms.

Low-melting ionic solids with stirring luminescent properties hold significant promise for optoelectronic applications. Here, we compare and contrast the structural and spectroscopic correlations of two highly luminescent organic-inorganic manganese halides (C4Py)(2)[MnCl4] and (C4Py)(2)[MnBr4], synthesized from their respective manganese halides and N-butyl pyridinium halide ionic liquids. Although both compounds exhibit very similar bulk structures (determined by single-crystal and powder X-ray diffraction) and overall similar electronic structures (as indicated by the density of states), they differ notably in their optical properties. The chloride salt, (C4Py)(2)[MnCl4], has a photoluminescence decay lifetime ten times longer than its bromide analogue, (C4Py)(2)[MnBr4]. Furthermore, PL-quantum yield of (C4Py)(2)[MnBr4] is 1.6 times higher than that of (C4Py)(2)[MnCl4], which was attributed to the heavy atom effect of bromine atoms, based on periodic density functional calculations (with and without spin-orbit coupling). Although photoluminescence is only exhibited in the solid state, EXAFS analysis confirms that the coordination environment of manganese is remarkably similar in crystalline and molten states, potentially suggesting that photoluminescence is associated with the long-range crystalline order, which is lost upon melting. Building on these fundamental studies, the potential of (C4Py)(2)[MnCl4] as a luminescent security ink for anticounterfeiting applications has been demonstrated.

Sensitive and selective fluorescent sensing of Ba2+ has attracted significant attention due to its relevance in environmental monitoring, industrial applications, and biological systems, as Ba2+ is highly toxic. Herein, we report on Ba2+ selective fluorescence sensing in aqueous solution by a fluorescent probe consisting of a dibenzo-18-crown-6 as a Ba2+ binding unit (ionophore) and a tetramethylated 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) fluorophore as a fluorescence reporter. This fluorescent probe showed an extraordinary Ba2+ induced fluorescence enhancement (FE) by a factor of 185 +/- 20 independently of the pH value (from 4 to 10), a high Ba2+ sensitivity with a limit of detection of (0.60 +/- 0.03) mM, and a high Ba2+ selectivity. Moreover, the high Ba2+-induced FE is caused by an off-switching of multiple fluorescence quenching processes within the fluoroionophore by Ba2+. Here, we observed that a cation switches off a photoinduced electron transfer (PET) and hampers aggregation between BODIPY dyes in aqueous solution.

Three mononuclear cobalt(II) complexes were synthesised from the reactions of 4-benzoyl-3-methyl-1-phenylpyrazol-5-ol (HQPh), 3-methyl-4-(4-methylbenzoyl)-1-phenylpyrazol-5-ol (HQPhMe), and 4-(4-ethylbenzoyl)-3methyl-1-phenylpyrazol-5-ol (HQPhEt) with CoCl2 center dot 6H2O in methanol. The compounds were characterised by conventional spectroscopic techniques, 1H and 13C NMR, UV-Visible, FT-IR spectroscopy, single-crystal X-ray crystallographic structural determinations (SC-XRD) and computational (DFT) techniques. Crystallographic data show a monoclinic system for 1 and a triclinic system for both 2 and 3. Molecular structure revealed a octahedral Co(II) centers in [Co(DMF)2(QPh)2] 1, [Co(DMF)(OH2)(QPhMe)2] 2, and [Co(DMF)(OH2)(QPhEt)2] 3. Complex 1 has a symmetric structure with two DMF ligands, while 2 and 3 are isostructural and asymmetric, featuring one DMF and one aqua ligand. The Cambridge Structural Database (CSD) Aromatic Analyser shows strong paralleldisplaced (2 and 3) and T-shaped (1, 2, and 3) stacking interactions, which significantly influence the binding parameters of these compounds. Hydrogen Bond Statistics identify several symmetry-independent strong hydrogen bonding, N center dot center dot center dot H-O-H center dot center dot center dot N (D-A distances: 2.84 & Aring;, 2.83 & Aring;) in compounds 2 and 3. DFT calculations further indicate that alkylphenyl substitution significantly affects the electronic properties of the complexes. Replacing a phenyl group with a methylphenyl group, and subsequently with an ethylphenyl group, results in decreased reactivity and increased molecular stability. These findings demonstrate that both alkylphenyl substituents and solvent environment strongly influence the geometry, supramolecular assembly, and electronic properties of QR complexes useful for functional applications.

The unique binding properties of ketohexoses with boronic acids present new opportunities for functional material design. We investigated the binding of D-fructose, L-sorbose, D-tagatose, and D-psicose with four boronic acids, i.e. phenylboronic acid (PBA), 3-acetamidophenylboronic acid (AcPBA), benzoxaborole (BOB), and 6-acetamidobenzoxaborole (AcBOB), in an aqueous environment using isothermal titration calorimetry (ITC), finding that D-psicose exhibits exceptional affinity, compared to other ketohexoses. The ketohexose sugars were efficiently converted into isopropylidene-protected methacrylate monomers for polymer formation. These polymers can be deprotected in an acidic environment to yield the side-chain functionalized glycopolymers, which provide a versatile platform for strong boronic acid-carbohydrate interactions for dynamic and advanced material design.

Skin cancer is increasing worldwide, with melanoma being its most aggressive and lethal form due to its high metastatic potential. Despite therapeutic advances, drug resistance remains a challenge, highlighting the need to explore new anticancer agents. Leptocarpha rivularis is a native plant of Chile, locally called "Palo negro", and is traditionally used in medicine by the Mapuche people. L. rivularis produces bioactive germacrene sesquiterpenoids with cytotoxic, antioxidant, anti-inflammatory and anti-angiogenic properties. This study reports for the first time the isolation of ovatifolin from aerial parts of L. rivularis and its identification by NMR and X-ray diffraction, together with its antiproliferative activity against two melanoma cell lines. The results show that ovatifolin has cytotoxic activity against the cell lines A2058 and A375, with an IC50 of 27.6 (90.2 µM) and 18.4 µg/mL (60.1 µM), respectively, evaluated by live-cell IncuCyte® analysis. Moreover, ovatifolin arrests colony formation in a clonogenic assay, with an IC50 of 3.26 (10.6 μM) and 3.65 µg/mL (11.9 μM) in these same cell lines. Therefore, ovatifolin increased intracellular ROS and decreased the mitochondrial membrane potential (ΔΨ m). Cell death studies using Annexin V showed that its cytotoxic activity is partially caused by non-specific apoptosis, which was corroborated by the caspase inhibitor Z-VAD with an incomplete recovery of the cell death process.

(Hg-2) and [(C6H5)HgS2CN(CH2C6H5)(CH2C6H4-p-OH)] (Hg-3) have been synthesized and characterized. The single crystal X-ray diffraction analyses reveal that Hg(II) core adopts distorted linear geometry fulfilled by one sulfur of the dithiocarbamate ligand and phenyl carbon. Another doubly bonded sulfur of dtc ligand exhibits intramolecular Hg & sdot;& sdot;& sdot;S Spodium bonding (SpB) interaction thereby leading to distortion in the linear geometry around Hg(II). The supramolecular framework of all three complexes is stabilized by weak intermolecular Hg & sdot;& sdot;& sdot;S SpB interactions along with S & sdot;& sdot;& sdot;H, C & sdot;& sdot;& sdot;H and O & sdot;& sdot;& sdot;H intermolecular interactions. The isomeric positions of the -OH group affects the supramolecular frameworks engendering single helical motifs held by O-H & sdot;& sdot;& sdot;C(Ar) and pair of O-H & sdot;& sdot;& sdot;S and C-H & sdot;& sdot;& sdot;S interactions in Hg-1 and Hg-3 respectively while Hg-2 displays a two-dimensional sheet like motif sustained by O & sdot;& sdot;& sdot;H -C(Ar) interactions. These interactions further have been investigated and correlated using Hirshfeld surface analyses and computational studies. The QTAIM and NBO analyses indicate that for Hg-2, the computed intermolecular Hg & sdot;& sdot;& sdot;S SpB interaction energies are 3.64 and 3.86 kcal & sdot;mol-1, respectively thereby suggesting the best stability of intermolecular Hg & sdot;& sdot;& sdot;S SpB interaction in the meta-isomer, Hg-2. This investigation provides newer insight into the factor affecting the supramolecular frameworks and Spodium bonding interactions in phenylmercury(II) dithiocarbamates.

exo-Methylene indanones and tetralones undergo Pd-catalyzed couplings with arene diazonium salts with divergent but in both cases high selectivity. In the case of indanones, the double bond is located exo to yield conformationally constrained chalcones, whereas tetralones react to afford 2-benzyl-1-naphthols via an endo-β-hydride elimination followed by tautomerization. Depending on the solvent used, exo-methylene indanones can undergo a monocoupling selectively or two successive coupling reactions with the introduction of two identical or two different aryl substituents. The second Heck coupling proceeds via an endo-selective β-hydride elimination to yield indenones.

Angiostrongylus cantonensis is a zoonotic parasitic nematode of growing global health concern, largely due to the limited efficacy of current anthelmintics such as albendazole. In this study, cubebina dibenzylbutyrolactole lignanwas isolated for the first time from Drimys andina (Winteraceae), a Chilean endemic plant, and evaluated for its antiparasitic activity. Chromatographic purification of fresh leaves yielded cubebin as a 3:2 epimeric mixture, with its structure confirmed by 500 MHz NMR and single-crystal X-ray diffraction. In vitro assays demonstrated potent anthelmintic activity against both first-stage (L1) and infective third-stage (L3) larvae of A. cantonensis, with EC50 values of 4.7 and 15.3 μM, respectively, making it approximately three times more potent than albendazole against L1 and comparably effective against L3. Cubebin exhibited no cytotoxicity toward monkey (Vero) or human (HaCaT) cell lines and no toxicity in Caenorhabditis elegans, indicating a favorable safety profile. In silico ADME analysis further revealed favorable pharmacokinetic and drug-likeness properties. These results highlight cubebin as a promising lead compound for the development of novel anthelmintic therapies targeting A. cantonensis and potentially other parasitic nematodes.

Transparent solid-state ionic conductors are emerging as next-generation materials for various modern optoelectronics and energy applications. In this study, an organic-inorganic hybrid metal halide is introduced, tris-N-butyl pyridinium nonachlorido-dibismuthate(III), (C(4)py)(3)[Bi2Cl9]. The material is an optically transparent solid-state ion conductor with high ionic conductivity at room temperature. Single crystal analysis reveals a structure composed of N-butyl pyridinium cations and [Bi2Cl9](3-) anions, formed by edge-sharing BiCl6 octahedra. The material is thermally stable up to 300 degrees C and undergoes a melting transition at 101.6 degrees C. Notably, it demonstrates unidirectional growth in thin films, boasting over 90% optical transparency in the visible wavelength and overall ionic conductivity of 10(-3) mS cm(-1) at room temperature. (C(4)py)(3)[Bi2Cl9] stands out as one of the first reported low-melting, optically transparent ionic solids, showcasing superior ion conduction and holding promise for applications such as electrochromic devices and energy storage.

Abstrakt Mikrokontaktdruck (µCP) stellt eine weitverbreitete Technik zur mikroskaligen Strukturierung von Oberflächen dar. In dieser Studie stellen wir eine polymergestützte µCP‐Methode zur Strukturierung (bioaktiver) glykosylierter Oberflächen vor, die unter hydratisierten Bedingungen abläuft. Der µCP wird erreicht, indem die Substrate mit einem strukturierten Polydimethylsiloxan‐ (PDMS‐)Stempel kontaktiert werden, auf dessen Oberfläche ein dopaminfunktionalisiertes Polymer gebunden ist. Die oberflächenfunktionalen Polymerbürsten fungieren als Ankergruppen für das Boronsäurederivat 6‐Aminobenzo[c][1,2]oxaborol‐1(3H)‐ol (ABOB), das als Tinte für den Mikrokontaktdruck eingesetzt wird. Die Methode wird angewandt, um drei verschiedene Oberflächen als Substrate zu strukturieren: (1) monosaccharidfunktionale Hydrogeloberflächen, die mit Aldosen (Glukose, Fukose, Galaktose) oder Ketosen (Fruktose, Sorbose) funktionalisiert sind, (2) glykosylierte Oberflächen mikroskaliger Polymerkügelchen und (3) Membranen von Säugetierzellen wie primären menschlichen Magenschleimhautzellen. Während des µCP‐Prozesses erfolgt der Übergang des ABOB‐Musters unter Ausbildung eines Kohlenhydrat‐ABOB‐Komplexes auf der Zieloberfläche unter vollständig hydratisierten und neutralen pH‐Bedingungen. Fluoreszenzmikroskopie‐Untersuchungen konnten den erfolgreichen Übertrag von ABOB‐Mustern auf Hydrogele, glykosylierte Mikropartikel sowie zelluläre Grenzflächen, also glykosylierte Oberflächen – mit klaren „tattooähnlichen“ Signaturen – nachweisen.

exo-Methylene indanones and tetralones undergo Pd-catalyzed couplings with arene diazonium salts with divergent but in both cases high selectivity. In the case of indanones, the double bond is located exo to yield conformationally constrained chalcones, whereas tetralones react to afford 2-benzyl-1-naphthols via an endo-β-hydride elimination followed by tautomerization. Depending on the solvent used, exo-methylene indanones can undergo a monocoupling selectively or two successive coupling reactions with the introduction of two identical or two different aryl substituents. The second Heck coupling proceeds via an endo-selective β-hydride elimination to yield indenones.

Three bioactive prenylated isoflavone natural products were synthesized for the first time, using a combination of Pd-catalyzed Suzuki-Miyaura coupling for installing the B-ring, microwave-promoted Claisen rearrangement of allyl ethers, and Ru-catalyzed olefin cross metathesis for obtaining the prenyl substituents. Careful consideration of the protecting group strategy turned out to be vital for the success of these total syntheses.

Microcontact printing (µCP) is a widely used technique for microscale surface patterning. In this study, we present a polymer-supported µCP method for the patterning of (bioactive) glycosylated surfaces under hydrated conditions. Patterning is achieved by direct contact with a grooved polydimethylsiloxane (PDMS) stamp, whose surface was grafted with a dopamine-containing polymer. The polymer brushes offer an anchor for the boronic acid derivative 6-aminobenzo[c][1,2]oxaborol-1(3H)-ol (ABOB), used as an ink for surface functionalization, to introduce patterns to three different surfaces as substrates: (1) monosaccharide-modified hydrogel surfaces possessing aldose (glucose, fucose, galactose) or ketose (fructose, sorbose) functions; (2) glycosylated surfaces of polymeric microspheres; and (3) the membranes of mammalian cells, such as human primary gastric cells and others. During µCP, ABOB patterns transferred to the target surface through the formation of carbohydrate-ABOB complexes at fully hydrated, neutral pH conditions. Fluorescence microscopy confirmed the successful transfer of ABOB patterns to glycosylated surfaces, with clear "tattoo-like" signatures observed on hydrogels, glycosylated particle surfaces and cellular interfaces.