The self-assembly of highly functionalized phenanthrene-DNA conjugates into supramolecular nanostructures is presented. DNA oligomers modified with phenanthrene residues at the 3'-end and internal positions self-assemble into spherical nanostructures. The nanospheres exhibit light-harvesting properties. Upon irradiation of phenanthrene, the excitation energy is transferred along phenanthrene units, resulting in phenanthrene-pyrene exciplex formation.

Toxoplasmosis, a disease caused by the apicomplexan parasite , affects up to one third of the global population. Although immunocompetent individuals rarely experience severe symptoms, those with immunodeficiencies may potentially face fatal disease. The frontline treatments are currently sulphadiazine and pyrimethamine, which suffer from adverse side effects, and lack efficiency in clearing parasite cysts from the muscles and brain of patients. To address the need for novel, more effective, and less toxic treatments, four new ferrocenyl benzimidazole complexes 15-18 were synthesised and evaluated against the ΔKu80:mNeonGreen strain of . Complexes 15 and 17 were found to be active with EC values of 17.9 and 17.5 μM respectively, with comparable activity to pyrimethamine, which had an EC value of 13.8 μM, and less effective than sulphadiazine, which had an EC value of 2.56 μM. Additionally, the compounds were found to be relatively non-toxic against HEK 293T and PNT1A human cell lines. Further investigations found that the complexes act by generating reactive oxygen species (ROS) through the ferrocenyl moiety. These complexes show potential for the development of new treatments against Toxoplasmosis.

FeNbO sonocatalysts were successfully synthesized by a simple hydrothermal route at pH values of 3, 5, 7, 9 and 11. The catalysts were characterized by XRD, XPS, TEM, SEM, N adsorption and DRS to analyse the effect of pH parameters on the physicochemical properties of the materials during hydrothermal synthesis. The sonocatalytic activity of FeNbO microspheres was evaluated by using acid orange 7 (AO7) as the simulated contaminant. The experimental results showed that the best sonocatalytic degradation ratio (97.45%) of organic dyes could be obtained under the conditions of an initial AO7 concentration of 10 mg L, an ultrasonic power of 200 W, a catalyst dosage of 1.0 g L, and a pH of 3. Moreover, the sonocatalysts demonstrated consistent durability and stability across multiple test cycles. After active species capture experiments and calculation of the energy band, a possible mechanism was proposed based on the special Fenton-like mechanism and the dissociation of HO. This research shows that FeNbO microspheres can be used as sonocatalysts for the purification of organic wastewater, which has a promising application prospect.

We report the synthesis of 4-nitrophenyl (4-NP) functionalised Pt(iv) complexes as a colorimetric strategy for monitoring Pt(iv) reduction in aqueous solution. Treatment of each 4-NP functionalised Pt(iv) complex with the biological reductant sodium ascorbate led to a colour change from clear to yellow, which was attributed to the reduction of Pt(iv) to Pt(ii) and simultaneous release of 4-nitroaniline. Trends in reduction profiles and a photocatalysed reduction for each Pt(iv) complex were observed.

Sulfones are fascinating and highly used functional groups, but current syntheses still have limitations. Here, a regiodivergent transition metal-free approach towards sulfones [()-allylic sulfones and α-sulfonyl-methyl styrenes] is reported. The method employs commercially available olefins, bases, additives, solvents, and sodium sulfinates (RSONa) and produces adducts in good yields. Considering that up to 4 reactions (bromination, dearomative rearrangement, E2, and S2) are happening, this approach is very efficient. The structures of key adducts were confirmed by X-ray crystallography.

Over a hundred non-canonical nucleotides have been found in DNA and RNA. Many of them are sensitive toward nucleophiles. Because known oligonucleotide synthesis technologies require nucleophilic conditions for deprotection, currently there is no suitable technology for their synthesis. The recently disclosed method regarding the use of 1,3-dithian-2-yl-methyl (Dim) for phosphate protection and 1,3-dithian-2-yl-methoxycarbonyl (Dmoc) for amino protection can solve the problem. With Dim-Dmoc protection, oligodeoxynucleotide (ODN) deprotection can be achieved with NaIO followed by aniline. Some sensitive groups have been determined to be stable under these conditions. Besides serving as a base, aniline also serves as a nucleophilic scavenger, which prevents deprotection side products from reacting with ODN. For this reason, excess aniline is needed. Here, we report the use of alkyl Dim (aDim) and alkyl Dmoc (aDmoc) for ODN synthesis. With aDim-aDmoc protection, deprotection is achieved with NaIO followed by KCO. No nucleophilic scavenger such as aniline is needed. Over 10 ODNs including one containing the highly sensitive -acetylcytidine were synthesized. Work on extending the method for sensitive RNA synthesis is in progress.

Acetals (, , and ) of andrographolide (), 14-deoxy-12-hydroxyandrographolide (), and isoandrographolide () were synthesized using benzaldehyde and heteroaromatic aldehydes. All the synthesized derivatives were characterized using H-NMR, C-NMR, mass spectrometry, UV, and IR. The compound was characterized a single-crystal X-ray diffraction study. All the compounds were tested against 60 cell lines of NCI. The acetals () of andrographolide () exhibited better activity than the acetals (, and ) of 12-hydroxyandrographolide () and isoandrographolide (). Preliminary studies suggested that acetals synthesized using benzaldehyde improved anticancer activity. Compound showed the highest growth inhibition of 90.97% against the leukaemia cancer cell line CCRF-CEM. Andrographolide and seven selected compounds were tested against the MDA-MB-231 breast cancer cell line. Compound showed the best activity with an IC value of 3 μM among all the tested compounds. Furthermore, this compound was subjected to cell cycle analysis and protein expression confirming apoptosis through the disruption of the mitochondrial potential membrane (Δ ).

1,3-Dipolar cycloaddition of nonstabilized azomethine ylides derived from α-C-H functionalization of tetrahydroisoquinoline for regio- and diastereoselective synthesis of spirooxindole-pyrrolidines is developed. A three-component reaction of readily available cyclic amine, aryl aldehydes, and olefinic oxindoles provides a pot, atom and step economy (PASE) approach for making spiro-heterocyclic compounds with biological interest.

We report an investigation of the complexation between a water soluble pillararene host (WP6) and a panel of hydrophobic cationic guests (G1 - G20) by a combination of H NMR spectroscopy and isothermal titration calorimetry in phosphate buffered saline. We find that WP6 forms 1:1 complexes with K values in the 10 - 10 M range driven by favorable enthalpic contributions. This thermodynamic dataset serves as blinded data for the SAMPL9 challenge.

Site Identification by Ligand Competitive Saturation (SILCS) is a molecular simulation approach that uses diverse small solutes in aqueous solution to obtain functional group affinity patterns of a protein or other macromolecule. This involves employing a combined Grand Canonical Monte Carlo (GCMC)-molecular dynamics (MD) method to sample the full 3D space of the protein, including deep binding pockets and interior cavities from which functional group free energy maps (FragMaps) are obtained. The information content in the maps, which include contributions from protein flexibilty and both protein and functional group desolvation contributions, can be used in many aspects of the drug discovery process. These include identification of novel ligand binding pockets, including allosteric sites, pharmacophore modeling, prediction of relative protein-ligand binding affinities for database screening and lead optimization efforts, evaluation of protein-protein interactions as well as in the formulation of biologics-based drugs including monoclonal antibodies. The present article summarizes the various tools developed in the context of the SILCS methodology and their utility in computer-aided drug design (CADD) applications, showing how the SILCS toolset can improve the drug-development process on a number of fronts with respect to both accuracy and throughput representing a new avenue of CADD applications.

We report here the efficient synthesis of 6,6´-diamido-2,2´-dipicolylamines (DA-DPAs) which could be applied to phosphate anion sensing pre-formed metal complexes. The design was based on the retrosynthetic analysis. This strategy enabled us to achieve the functionalized DA-DPAs in satisfactory yields with high purity using the Boekelheide rearrangement. Meanwhile, all the intermediates could be easily purified by silica gel column chromatography.

Haloboration, the addition of B-X (X = Cl, Br, I) across an unsaturated moiety , C[double bond, length as m-dash]Y or C[triple bond, length as m-dash]Y (Y = C, N, ), is dramatically less utilised than the ubiquitous hydroboration reaction. However, haloboration of alkynes in particular is a useful tool to access ambiphilic 1,2-disubstituted alkenes. The stereochemical outcome of the reaction is easily controlled and the resulting products have proven to be valuable building blocks in organic synthesis and materials chemistry. This review aims at providing the reader with a brief summary of the historic development and of the current mechanistic understanding of this transformation. Recent developments are discussed and select examples demonstrating the use of haloboration products are given with a focus on the major areas, specifically, natural product synthesis and the development of boron-doped polycyclic aromatic hydrocarbons (B-PAHs).

In an effort to synthesize a library of bioactive molecules, we present an efficient synthesis of fused-thiazole derivatives of natural products and approved drugs by using an environmentally usable solvent, acetic acid, and without any external reagent. Cholestenone, ethisterone, progesterone, and nootkatone-derived epoxyketones have been utilized to synthesize 50 novel compounds. The plausible mechanism of the reaction has been determined by theoretical calculation using M06-2X/6-31+G(d,p). These novel molecules have been tested against cancer cell lines and pathogenic bacterial strains. Several ethisterone-based fused-thiazole compounds are found to be potent growth inhibitors of cancer cell lines at submicromolar concentrations.

In this study we aim to identify the optimal cellulose extraction protocol for C dating of wood, with a focus on glacial trees. To achieve this, we compare three cellulose extraction methods on the basis of cellulose yield and C age. The study is conducted on 12 wood samples of different species, in varying states of preservation with ages covering the full C age range. Cellulose is extracted from each sample following three different protocols selected from the literature: ABA-B, BABAB and 2Chlorox. The extracted cellulose was graphitised and dated with the MICADAS (Mini Carbon Dating System) at the ETH AMS laboratory. Although all three methods are considered efficient, the BABAB protocol, despite being a more aggressive procedure, allows the extraction of a sufficient amount of cellulose to be C dated and leads to the most reliable results, particularly for very old and background samples (samples with C content of zero).

Androgen-deprivation therapy (ADT) is only a palliative measure, and prostate cancer invariably recurs in a lethal, castration-resistant form (CRPC). Prostate cancer resists ADT by metabolizing weak, adrenal androgens to growth-promoting 5α-dihydrotestosterone (DHT), the preferred ligand for the androgen receptor (AR). Developing small-molecule inhibitors for the final steps in androgen metabolic pathways that utilize 17-oxidoreductases required probes that possess fluorescent groups at C-3 and intact, naturally occurring functionality at C-17. Application of the Pictet-Spengler condensation to substituted 4-(2-aminoethyl)coumarins and 5α-androstane-3-ones furnished spirocyclic, fluorescent androgens at the desired C-3 position. Condensations required the presence of activating C-7 amino or N,N-dialkylamino groups in the 4-(2-aminoethyl)coumarin component of these condensation reactions. Successful Pictet-Spengler condensation, for example, of DHT with 9-(2-aminoethyl)-2,3,6,7-tetrahydro-1H,5H,11H-pyrano[2,3-f]pyrido[3,2,1-ij]quinolin-11-one led to a spirocyclic androgen, (3R,5S,10S,13S,17S)-17-hydroxy-10,13-dimethyl-1,2,2',3',4,5,6,7,8,8',9,9',10,11,12,12',13,13',14,15,16,17-docosahydro-7'H,11'H-spiro-[cyclopenta[a]phenanthrene-3,4'-pyrido[3,2,1-ij]pyrido[4',3':4,5]pyrano[2,3-f]quinolin]-5'(1'H)-one. Computational modeling supported the surrogacy of the C-3 fluorescent DHT analog as a tool to study 17-oxidoreductases for intracrine, androgen metabolism.

The growth mechanism of silver nanowires (AgNWs) in solution has been thoroughly investigated and it has been demonstrated that factors like oxidative etching and inclusion of Cl ions in the reaction system play critical roles in the formation of AgNWs. This research is the first to report the growth mechanism of AgNWs in the solid state on a chitosan polymer film with respect to factors such as oxidative etching, Cl ions and time. The AgNW synthetic method is a green process that involves aqueous solvents for film preparation and ambient conditions for AgNW growth. It is demonstrated that the source of the silver precursor for this solid state AgNW growth is the cuboidal AgCl nanoparticles that form during the solution preparation. Furthermore, it is shown that the 〈111〉 crystal faces of these cuboidal AgCl nanoparticles are the nucleation sites of AgNW growth. Unlike solution-based AgNW synthetic processes, the AgNWs generated by the chitosan film-based method are irregular and present lateral as well as longitudinal growth, which suggests a slightly different mechanism from the solution-based AgNW growth.

Cu-Catalyzed, ligand and base free cross-coupling of aryl boronic acids with primary and secondary amines has been reported. This 'Chan-Evans-Lam' reaction has revealed that at room temperature, catalytic copper(II) acetate and ceric ammonium nitrate (CAN) as an oxidant, N-arylation can result in an effective C-N bond formation. This air stable, practical, robust protocol enables a variety of functional group tolerance on both boronic acid and amine partners.

The synthesis of new C fullerene derivatives functionalized with thiophene moieties as well as with electron donating or electron withdrawing groups, bromine (Br) or cyano (CN), respectively, using Bingel reactions is reported. The synthesized derivatives were used as the electron transporting materials (ETMs) in inverted perovskite solar cells (PSCs). Compared to devices fabricated with [6,6]-phenyl-C-butyric acid methyl ester (PCBM), the new derivatives showed similar electrochemical properties and electron mobilities. However, PSCs based on the new derivatives synthesized in this work exhibited higher power conversion efficiencies (PCEs) than PCBM based devices, which were ascribed to their better passivation ability, likely due to specific interactions between the fullerene addend and the perovskite layer surface. Devices based on the fullerene bearing the CN group exhibited an additionally improved efficiency due to the increased dielectric constant ( ) of this derivative. These results show that the new functionalized fullerene derivatives can act as efficient ETMs in inverted PSCs.

Halogen bonding interactions are often discussed in terms of an area of positive electrostatic potential on the halogen center along the bond axis called the σ-hole, yet various authors have noted a lack of completeness in this model. The nature of the XB interaction is explored from the perspective of bonding theories beginning from models that explain the electrostatic σ-hole and continuing to orbital-based donor-acceptor descriptions in which the donor lone pair MO mixes with the acceptor R-X and R-X* MOs to form a set of XB MOs related to three-center-four-electron bonding in hypervalent molecules. The strength of the XB interaction for a large series of RX···Cl and RX···SeMe complexes correlate well with the energy of the acceptor R-X* MO and the contribution of the halide to the R-X and R-X* MOs, factors relevant to favourable overlap with the donor lone pair. An orbital-based focus accounts for the partial covalency of the XB interaction and can be extended to descriptions of enzymatic dehalogenation mechanisms. Applications of this MO perspective to the deiodination of thyroid hormones by the iodothyronine deiodinases and a possibly related mechanism of inhibition are discussed.

The synthesis and characterization of three new organic hydrazines containing BODIPY dyes is described. The respective aminomethyl complexes were also synthesized to aid in the assignment of the physical properties that were hydrazine-based vs. BODIPY-based. Incorporation of a BODIPY dye into an organic hydrazine introduced a reduction event (average value of -1.70 V vs. CpFe/CpFe). Although two irreversible oxidation events were observed, it was unclear whether the oxidation events arose from BODIPY-based or amine/hydrazine-based oxidations. The respective BODIPY-appended hydrazine complexes exhibited excited state lifetimes on the order of 2-6 ns, suggesting the presence of a singlet excited state. The excited state lifetimes of the BODIPY-appended hydrazine complexes were about a factor of ten greater than the respective aminomethyl complexes. Computational analysis showed that by appending a BODIPY dye to a hydrazine fragment the hydrazine fragment becomes more susceptible to transfer H equivalents as protons and hydrides as opposed to H-atoms, which occurs with common organic hydrazines. Computational analysis also revealed that the BODIPY-based redox events can be used to manipulate the mechanism for H transfer from the BODIPY-appended hydrazine, where a BODIPY-based reduction favors H-atom transfer and a BODIPY-based oxidation favors proton transfer followed by hydride transfer.

We report the synthesis of a new acyclic CB[n]-type host (1) that features a central glycoluril trimer capped by triptycene sidewalls. Host 1 has good solubility in water (≈ 3 mM) and does not undergo strong self-association (K = 480 M). We probed the geometry of the complexes by analyzing the complexation induced changes in the H NMR spectra and measured the complexation thermodynamics by isothermal titration calorimetry. The conformation of 1 and its packing in the solid state was revealed by single crystal x-ray diffraction measurements.