Cu(OTf)-catalyzed C3 aza-Friedel-Crafts alkylation of indoles with ,-acetals.

An efficient approach to access functionalized indole derivatives has been developed through Cu(OTf)-catalyzed C3 aza-Friedel-Crafts alkylation of substituted indoles 5a-5m, -methyl-pyrrole with linear ,-acetals 4a-4l. As a result, a series of C3 amide aza-alkylated indole derivatives 6a-6ag and 7 were synthesized in moderate to excellent yields.

Separation, quantification and characterisation of the pigment produced by TD16.

Fungal pigments are important natural products with a wide range of applications. In this study, the purple-red pigment produced by the fungus TD16 (TD16 pigment) was separated with acidulated ethyl acetate and purified by silica gel column chromatography. Results of UV-visible spectrum and HPLC analyses showed that TD16 pigment is a new polyketide pigment with three absorption peaks at 228, 272 and 527 nm and a retention time of 11.

Copper-catalyzed synthesis of α-ketoamides using water and dioxygen as the oxygen source.

The reaction employing HO and O as the co-oxygen source in the catalytic synthesis of α-ketoamides is described. This copper-catalyzed reaction is carried out in a tandem manner constituted by the hydroamination of alkyne, hydration of vinyl-Cu complex and subsequent oxidation. Isotope labeling and radical capture experiments reveal that the oxygen atom of α-ketone at α-ketoamides derives from O and the oxygen atom of amide group originates from HO.

Copper(i)-catalyzed intermolecular cyanoarylation of alkenes: convenient access to α-alkylated arylacetonitriles.

A novel Cu(i)-catalyzed intermolecular cyanoarylation of alkenes with diaryliodonium salts as a radical arylating reagent and tetra-butylammonium cyanide as an electrophilic cyanating reagent was established. A broad range of α-alkylated arylacetonitriles were efficiently constructed in good to excellent yields under base- and oxidant-free and mild conditions.

A Bifunctional Luminescent Metal-Organic Framework for the Sensing of Paraquat and Fe Ions in Water.

The hydrothermal reaction of Zn ions with a mixture of two ligands, Hcptpy and H btc (Hcptpy=4-(4-carboxyphenyl)-2,2':4',4''-terpyridine; H btc=1,3,5-benzenetricarboxylic acid), led to the formation of a 3D metal-organic framework (MOF) with 1D channels, [Zn (cptpy)(btc)(H O)] (1), which was structurally characterized by using single-crystal X-ray diffraction (SXRD). In MOF 1, two independent Zn ions were interconnected by btc ligands to form a 1D chain, whilst adjacent Zn ions were alternately bridged by cptpy ligands to generate a 2D sheet, which was further linked by 1D chains to form a 3D framework with a new (3,3,4,4)-connected topology. Furthermore, compound 1 also exhibited excellent stability towards air and water and, more importantly, luminescence experiments indicated that it could serve as a probe for the sensitive detection of paraquat (PAQ) and Fe ions in aqueous solution.

TBAI-catalyzed selective synthesis of sulfonamides and β-aryl sulfonyl enamines: coupling of arenesulfonyl chlorides and sodium sulfinates with tert-amines.

A simple, practical and metal-free method has been developed for the synthesis of sulfonamides and β-arylsulfonyl enamines via the selective cleavage of C-N and C-H bonds through the iodine-catalyzed oxidation of arenesulfonyl chlorides and sodium sulfinates with tert-amines. The method uses commercially available inexpensive catalysts and oxidants, and has a wide substrate scope and operational simplicity.

Metal-free difunctionalization of alkynes leading to alkenyl dithiocyanates and alkenyl diselenocyanates at room temperature.

A simple and practical method for the synthesis of alkenyl dithiocyanates and alkenyl diselenocyanates has been developed via stereoselective difunctionalization of alkynes with NaSCN or KSeCN at room temperature. Through this methodology, a series of alkenyl dithiocyanates and alkenyl diselenocyanates could be efficiently and conveniently obtained in moderate to good yields under mild and metal-free conditions by the simple use of oxone and PhI(OAc)2 as the oxidants.

Palladium-catalyzed selective synthesis of 3,4-dihydroquinazolines from electron-rich arylamines, electron-poor arylamines and glyoxalates.

A simple palladium-catalyzed selective synthesis of structurally diverse 3,4-dihydroquinazolines from electron-rich arylamines, electron-poor arylamines and glyoxalates has been developed under mild conditions. This reaction is carried out in a tandem manner constituted by the condensation of arylamines and glyoxalates, the selective Diels-Alder cycloaddition and oxidation processes, in which 4-nitrothiophenol was used as the key ligand.

Facile Access to YC (2n = 92-130) and Crystallographic Characterization of YC@C(1660)-C: A Giant Nanocapsule with a Linear Carbide Cluster.

A series of giant metallofullerenes YC (2n = 92-130) have been successfully obtained through the treatment of the fraction enriched by 1,2-dichlorobenzene with SnCl. Subsequent chromatographic separation gives a pure sample with a composition of YC. Crystallographic results reveal that this endohedral takes the carbide form, namely YC@C(1660)-C, representing as the largest metallofullerene that has been characterized by crystallography to date.

Interaction between fasudil hydrochloride and bovine serum albumin: spectroscopic study.

The interaction between fasudil hydrochloride (FSD) and bovine serum albumin (BSA) was investigated using fluorescence and ultraviolet spectroscopy under imitated physiological conditions. The Stern-Volmer quenching model has been successfully applied and the results revealed that FSD could quench the intrinsic fluorescence of BSA effectively via static quenching. The binding constants and binding sites for the BSA-FSD system were evaluated.

Study on the interaction between Besifloxacin and bovine serum albumin by spectroscopic techniques.

The interaction between Besifloxacin (BFLX) and bovine serum albumin (BSA) was investigated by spectroscopic (fluorescence, UV-Vis absorption and circular dichroism) techniques under imitated physiological conditions. The experiments were conducted at different temperatures (298, 304 and 310 K) and the results showed that the BFLX caused the fluorescence quenching of BSA through a static quenching procedure. The binding constant (Ka), binding sites (n) were obtained.

Study on the interaction between 21-(Ph-NN)-NCTPP and bovine serum albumin by spectroscopic techniques.

The interaction between 21-(Ph-NN)-NCTPP and bovine serum albumin (BSA) was investigated by fluorescence and ultraviolet-visible (UV-Vis) spectroscopy under imitated physiological conditions. The results showed that the intrinsic fluorescence of BSA was quenched strongly by 21-(Ph-NN)-NCTPP. The binding constants (Ka) and the binding sites (n) were obtained at three different temperatures (298, 304, and 310K).

Spectroscopic analyses on interaction of bovine serum albumin with novel spiro[cyclopropane-pyrrolizin].

The interaction between novel spiro[cyclopropane-pyrrolizin] (NSCP) and bovine serum albumin (BSA) was analyzed by fluorescence and ultraviolet-visible (UV-Vis) spectroscopy at 298 K, 304 K and 310 K under simulative physiological conditions. The results showed that NSCP can effectively quench the intrinsic fluorescence of BSA via static quenching. The binding constants, binding sites of NSCP with BSA were calculated.

Study on the interaction between carbonyl-fused N-confused porphyrin and bovine serum albumin by spectroscopic techniques.

The interaction between carbonyl-fused N-confused porphyrin (CF-NCP) and bovine serum albumin (BSA) was investigated by fluorescence and ultraviolet-visible (UV-Vis) spectroscopy. The results indicated that CF-NCP has strong ability to quench the intrinsic fluorescence of BSA by forming complexes. The binding constants (Ka), binding sites (n) were obtained.

Interaction between pirenoxine and bovine serum albumin in aqueous solution.

This work concerns the interaction of prenoxine sodium (PRX) and bovine serum albumin (BSA), which was conducted by spectroscopic means: fluorescence spectra, ultraviolet-visible spectra (UV-vis) and circular dichroism spectra (CD spectra) in physiological conditions. The results revealed the PRX can quench the fluorescence of BSA remarkably in aqueous solution. The quench mechanism has been obtained after corrected the fluorescence intensities for inner filter effects.

Spectroscopic studies on the interaction of Phacolysin and bovine serum albumin.

The interaction between Phacolysin (PCL) and bovine serum albumin (BSA) under imitated physiological conditions was investigated by spectroscopic (fluorescence, UV-Vis absorption and Circular dichroism) techniques. The experiments were conducted at different temperatures (294K, 302K, 306K and 310K) and the results showed that the PCL caused the fluorescence quenching of BSA through a static quenching procedure. The binding constant (Ka), binding sites (n) were obtained.

The investigation of the interaction between Tropicamide and bovine serum albumin by spectroscopic methods.

The fluorescence and ultraviolet-visible (UV-Vis) spectroscopy were explored to study the interaction between Tropicamide (TA) and bovine serum albumin (BSA) at three different temperatures (292, 301 and 310K) under imitated physiological conditions. The experimental results showed that the fluorescence quenching mechanism between TA and BSA was static quenching procedure. The binding constant (Ka), binding sites (n) were obtained.

A highly porous 4,4-paddlewheel-connected NbO-type metal-organic framework with a large gas-uptake capacity.

A highly porous 4,4-paddlewheel-connected NbO-type metal-organic framework (HNUST-2, HNUST represents Hunan University of Science and Technology) has been designed and synthesized by self-assembling [Cu₂(COO)₄] SBUs with a nanosized tetracarboxylate ligand prolonged by alkyne groups, 5,5'-(naphthalene-1,4-diylbis(ethyne-2,1-diyl))diisophthalic acid (H₄NDED). HNUST-2 exhibits high structural stability, a porous non-interpenetration framework with open metal sites and excellent gas-uptake capacity. This MOF material possesses a high BET surface area of 2366 m² g⁻¹, a large unsaturated excess and total H₂ uptake of 4.

Spectroscopic studies on the interaction of carteolol hydrochloride and urea-induced bovine serum albumin.

The interaction of carteolol hydrochloride, to 0.2 mol L(-1) urea-induced bovine serum albumin in aqueous solution has been first investigated by fluorescence spectra and ultraviolet-visible (UV-vis) spectra at pH 7.40.

Spectroscopic studies on the interaction of BSA and 5-spiro-3'-piperidine-2″-spiro-3″-indole-4',2″-diones.

The interaction of 5-spiro-3'-piperidine-2″-spiro-3″-indole-4',2″-diones (SPSDs), an anti-tumor drug, to bovine serum albumin (BSA) in aqueous solution has been investigated by fluorescence spectra and ultraviolet-visible (UV-vis) spectra at pH 7.40. We have studied the effect of four substituents on the SPSD for the first time.

The investigation of the interaction between Oxymetazoline hydrochloride and mucin by spectroscopic approaches.

The fluorescence and ultraviolet spectroscopy were explored to study the interaction between Oxymetazoline hydrochloride (OMZH) and mucin under imitated physiological condition. The results demonstrated that the fluorescence quenching mechanism between OMZH and mucin is a combined quenching process. The binding constants (K(a)), binding sites (n) and the corresponding thermodynamic parameters (ΔG, ΔH, and ΔS) of the interaction system were calculated at different temperatures.

Spectroscopic investigation on the intermolecular interaction between N-confused porphyrins-(3-methylisoxazole) diad and bovine serum albumin.

The intermolecular interaction between N-confused porphyrins-(3-methylisoxazole) diad (NCP-(3-methylisoxazole)) and bovine serum albumin (BSA) has been investigated through fluorescence and ultraviolet spectroscopy at different temperatures under imitated physiological conditions. The results showed that the fluorescence of BSA was quenched by NCP-(3-methylisoxazole) through a combined quenching procedure. The characteristics of NCP-(3-methylisoxazole)⋯BSA interaction (including interaction nature, interaction conformation, binding constants, binding sites, binding distance, thermodynamic parameters, etc.

A study on the interaction between 3-spiro-piperidones and bovine serum albumin using spectroscopic approaches.

The interaction between 3-spiro-2'-pyrrolidine-3'-spiro-3″-piperidine-2,3″-dione (PPD) and bovine serum albumin (BSA) in aqueous solution was studied using fluorescence and UV-vis spectroscopy. Fluorescence emission data revealed that BSA (1.00 × 10(-5)  mol/L) fluorescence was statically quenched by PPD at various concentrations, which implies that a PPD-BSA complex was formed.

Spectroscopic analysis of the interaction between thiazolo[2,3-b]pyrimidine analogues and bovine serum albumin.

The interaction between thiazolo[2,3-b]pyrimidine (TZPM) analogues and bovine serum albumin (BSA) was investigated by fluorescence spectroscopy and UV-Vis spectroscopy at two different temperatures (299 and 307K) under imitated physiological conditions. The results indicate that both static quenching and dynamic quenching contribute to the fluorescence quenching of BSA by TZPM. The binding constant (K(a)) and binding sites (n) were calculated from the obtained spectra.