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Pristine BODIPY compounds have negligible efficiency to generate the excited triplet state and singlet oxygen. In this report, we show that attaching a good electron donor to the BODIPY core can lead to singlet oxygen formation with up to 58 % quantum efficiency. For this purpose, BODIPYs with meso-aryl groups (phenyl, naphthyl, anthryl, and pyrenyl) were synthesized and characterized. The fluorescence, excited triplet state, and singlet oxygen formation properties for these compounds were measured in various solvents by UV/Vis absorption, steady-state and time-resolved fluorescence methods, as well as laser flash photolysis technique. In particular, the presence of anthryl and pyrenyl showed substantial enhancement on the singlet oxygen formation ability of BODIPY with up to 58 % and 34 % quantum efficiency, respectively, owing to their stronger electron-donating ability. Upon the increase in singlet oxygen formation, the fluorescence quantum yield and lifetime values of the aryl-BODIPY showed a concomitant decrease. The increase in solvent polarity enhances the singlet oxygen generation but decreases the fluorescence quantum yield. The results are explained by the presence of intramolecular photoinduced electron transfer from the aryl moiety to BODIPY core. This method of promoting T1 formation is very different from the traditional heavy atom effect by I, Br, or transition metal atoms. This type of novel photosensitizers may find important applications in organic oxygenation reactions and photodynamic therapy of tumors.

Here we provide the first detailed biochemical study of a noncanonical E1-like enzyme with broad specificity for cognate ubiquitin-like (Ubl) proteins that mediates Ubl protein modification and sulfur mobilization to form molybdopterin and thiolated tRNA. Isothermal titration calorimetry and in vivo analyses proved useful in discovering that environmental conditions, ATP binding, and Ubl type controlled the mechanism of association of the Ubl protein with its cognate E1-like enzyme (SAMP and UbaA of the archaeon Haloferax volcanii, respectively). Further analysis revealed that ATP hydrolysis triggered the formation of thioester and peptide bonds within the Ubl:E1-like complex. Importantly, the thioester was an apparent precursor to Ubl protein modification but not sulfur mobilization. Comparative modeling to MoeB/ThiF guided the discovery of key residues within the adenylation domain of UbaA that were needed to bind ATP as well as residues that were specifically needed to catalyze the downstream reactions of sulfur mobilization and/or Ubl protein modification. UbaA was also found to be Ubl-automodified at lysine residues required for early (ATP binding) and late (sulfur mobilization) stages of enzyme activity revealing multiple layers of autoregulation. Cysteine residues, distinct from the canonical E1 'active site' cysteine, were found important in UbaA function supporting a model that this noncanonical E1 is structurally flexible in its active site to allow Ubl~adenylate, Ubl~E1-like thioester and cysteine persulfide(s) intermediates to form.

Background The cochineal scale, Porphyrophora sophorae (Hemiptera: Coccoidea, Margarodidae), is one of the most serious arthropod pests of Chinese liquorice, Glycyrrhiza uralensis (Fabaceae), an important medicinal herb. The adult females tend to deposit the ovisacs in soil relatively far away from liquorice plants. After hatching, neonates move out of the soil and may use chemical cues to search for new hosts. Results We collected and analysed the volatiles from soils with and without liquorice roots, and chromatographic profiles revealed hexanal, β-pinene and hexanol as potential host-finding cues for P. sphorae. The attractiveness of these compounds to neonates was studied in the laboratory using four-arm olfactometer bioassays. The larvae showed a clear preference for β-pinene over hexanal and hexanol, as well as all possible combinations of the three compounds. In addition, a field experiment confirmed that β-pinene was significantly more attractive than hexanal and hexanol. Conclusion Newly eclosed larvae of P. sphorae exploit root volatiles as chemical cues to locate their host plant. β-Pinene proved to be the major chemical cue used by P. sphorae neonates searching for roots of their host plant. © 2016 Society of Chemical Industry.

A novel metal-doping strategy was developed for the construction of iron-decorated microporous aromatic polymers with high small-gas-uptake capacities. Cost-effective ferrocene-functionalized microporous aromatic polymers (FMAPs) were constructed by a one-step Friedel-Crafts reaction of ferrocene and s-triazine monomers. The introduction of ferrocene endows the microporous polymers with a regular and homogenous dispersion of iron, which avoids the slow reunion that is usually encountered in previously reported metal-doping procedures, permitting a strong interaction between the porous solid and guest gases. Compared to ferrocene-free analogues, FMAP-1, which has a moderate BET surface area, shows good gas-adsorption capabilities for H2 (1.75 wt % at 77 K/1.0 bar), CH4 (5.5 wt % at 298 K/25.0 bar), and CO2 (16.9 wt % at 273 K/1.0 bar), as well as a remarkably high ideal adsorbed solution theory CO2 /N2 selectivity (107 v/v at 273 K/(0-1.0) bar), and high isosteric heats of adsorption of H2 (16.9 kJ mol(-1) ) and CO2 (41.6 kJ mol(-1) ).

As negative feedback regulators of cytokine signaling, suppressor of cytokine signaling proteins are induced by interleukins and various peptide hormones and may prevent sustained activation of signaling pathways. In particular, suppressor of cytokine signaling-3 (SOCS-3) plays pivotal roles in the development and progression of various cancers and exerts pleiotropic effects on cell proliferation and apoptosis. In recent years, abnormal expression of SOCS-3 and its multiple functions have been extensively investigated in human carcinomas, particularly in prostate cancer. SOCS-3 can act as an oncogene or a tumor suppressor depending on the cellular context. In this review, we focus on the role of SOCS-3 in prostate cancer development and prognosis, as well as the potential of SOCS-3 as a therapeutic target and diagnostic marker.

We report the synthesis, crystallographic, optical, and triplet and singlet oxygen generation properties of a series of BF2 -rigidified partially closed chain bromotetrapyrroles as near infrared emitters and photosensitizers. These novel dyes were efficiently synthesized from a nucleophilic substitution reaction between pyrroles and the 3,5-bromo-substituents on the tetra- and hexabromoBODIPYs and absorb in the near-infrared region (681-754 nm) with high molar extinction coefficients. Their fluorescent emission (708-818 nm) and singlet oxygen generation properties are significantly affected by alkyl substitutions on the two uncoordinated pyrrole units of these dyes and the polarity of solvents. Among them, dyes 4 ca and 4 da show good singlet oxygen generation efficiency and good NIR fluorescence emission (fluorescence quantum yields of 0.14-0.43 in different solvents studied).

Novozym-435-initiated reaction of cyclohexanones, nitrostyrenes, 4-nitrobenzaldehyde, and acetamide results in the formation of spirooxazines in a single step.

Metal-organic frameworks (MOFs) provide intriguing platforms for the design of responsive materials. It is challenging to mobilize as many components as possible of a MOF to collaboratively accomplish multiple responsive properties. Here, reversible photochromism, piezochromism, hydrochromism, ionochromism, and luminescence modulation of an ionic Eu(III) MOF is reported furnished by cationic electron-deficient viologen units and exchangeable guest anions. Mechanistically, the extraordinarily versatile responsive properties are owed to electron transfer (ET), charge transfer (CT), and energy transfer, involving viologen as electron acceptor, anion as electron donor, luminescing Eu(III) as energy donor, and anion-viologen CT complex or ET-generated radical as energy acceptor (luminescence quencher). Moreover, guest anions and waters provide flexible handles to control the ET-based responsive properties. Water release/reuptake or exchange with organic solvents can switch on/off the response to light, while reversible anion exchange can disenable or awaken the responses to pressure, light, and water release/reuptake. The impacts of water and anions on ET are justified by the high polarity and hydrogen-bonding capability of water, the different electron donor strength of anions, and the strong I- -viologen CT interactions. The rich responsive behaviors have great implications for applications such as pressure sensors, iodide detection, and chemical logic gates.

A facile and simple route for the direct preparation of substituted 3-methylcyclohex-2-enone via Aldol-Robinson cascade reaction of aldehydes and acetones catalyzed by the new catalytic system of L-lysine/imidazole in n-heptane with 0.5% water was reported. A variety of substrates can participate in the process efficiently. The merits of this method included inexpensive and easily available starting materials and catalyst, the good yield of products and the straightforward work-up.

Enzymatic multicomponent reactions (MCR) are very powerful for complex organic synthesis with environmentally friendly, highly efficient and selective characters, while sometimes having some unavoidable shortages such as narrow substrate scope and so on. Herein, this work demonstrated how to redesign one previously reported lipase-catalyzed MCR to achieve more broad substrates and more efficient synthesis. Twelve new spirooxazino derivatives with different substitutions were obtained in moderate to good yield, while all of them could not be synthesized using the previous route. Reaction conditions such as enzymes, enzyme concentration, amides and ratio of substrates were screened. Furthermore, particularly interesting is that chiral spirooxazino could also be obtained through a further developed two-enzymatic MCR process in one pot. As a domino process simultaneously constructing six new C-C/N bonds and two rings in only one step, the work will remarkably expand the application scope of enzymatic MCR for simple and green synthesis of complex compounds.

Objectives The criteria for evaluating cerebral artery stenosis by transcranial Doppler sonography are inconsistent. We aimed to identify the accuracy of transcranial Doppler criteria compared with digital subtraction angiography for diagnosis of anterior circulation artery stenosis. Methods A total of 170 patients who underwent transcranial Doppler sonography and digital subtraction angiography were recruited. The anterior circulation arteries were evaluated by transcranial Doppler sonography and digital subtraction angiography. We defined the best cutoff value for substantial anterior circulation artery stenosis by receiver operating characteristic curve analyses and calculated the sensitivity, specificity, and positive and negative predictive values. Results An anterior circulation artery peak systolic velocity (PSV) of 120 cm/s had the largest area under the receiver operating characteristic curve compared with PSVs of 110, 130, and 140 cm/s and mean flow velocities of 60, 70, and 80 cm/s. The sensitivity, specificity, false-positive rate, false-negative rate, accuracy, positive predictive value, negative predictive value, positive likelihood ratio, negative likelihood ratio, and Youden index for transcranial Doppler sonography were 90.6%, 85.0%, 15.0%, 9.4%, 87.9%, 87.2%, 88.9%, 6.04, 0.11, and 0.756, respectively. The reliability index included the agreement rate and κ value, which were 87.9% and 0.757. Conclusions A PSV of 120 cm/s combined with additional parameters was an accurate criterion for diagnosing anterior circulation artery stenosis. Transcranial Doppler sonography could be considered a valuable method for screening diagnosis of cerebral artery stenosis.

Tetrabenzotriazacorrole (TBC) complexes are tetrapyrrolic aromatic corrole macrocycles, which are phthalocyanine (Pc)-like and are new members of the porphyrin family. A TBC molecule is a chemically reduced Pc. Because of their distinct structural, electronic and UV–vis spectroscopic features, and electrochemical behavior, TBCs have many potential applications. This paper reviews the latest synthesis, characterization, properties, and applications of TBC compounds. The opportunities for further research on TBCs are also discussed.

A simple, efficient and eco-friendly route has been developed for the synthesis of β-mercapto diketones via a multicomponent reaction of an aldehyde, acetylacetone and thiol in water. This methodology affords a number of β-mercapto diketone derivatives in moderate to good yields.

We previously reported that crude rapeseed peptides (CRPs) and peptide fractions (RP25 and RP55) prepared from aqueous enzymatic extraction of rapeseed exhibited marked antioxidant activities, among which RP55 showed the most potent effects. In the present study, RP55 was further purified using consecutive chromatographic methods for identification of antioxidant peptides. The α,α-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging effects of peptides were measured at each purification step to evaluate the antioxidant activities. RP55 was first fractionated by anion-exchange chromatography, and three fractions (E1, E2, and E3) were obtained. All of them showed significantly lower scavenging activities compared to RP55, which was very probably due to the remarkable loss of tannin during the separation. Next, the active fraction E2 with higher protein content was sequentially purified by gel filtration chromatography (GFC) and reversed-phase high performance liquid chromatography (RP-HPLC). The purified peptide, of which the median effective dose (ED50) value for DPPH radical scavenging was 0.063 mg/mL, was identified to be Pro-Ala-Gly-Pro-Phe (487 Da) using electrospray ionization (ESI) mass spectrometry. The unique amino acid composition and sequence in the peptide might play an important role in expression of its antioxidant activity.

A series of spirooxindole derivatives are synthesized using isatin derivatives, cyanoacetamide and 1,3-dicarbonyl compounds as starting materials via one-pot enzymatic or two-step chemo-enzymatic domino reactions.

The asymmetric synthesis of α-trifluoromethyl amides is accomplished with an enzyme-nanometal cocatalyst.

Graft copolymerization of water-soluble monomers containing quaternary ammonium onto PVA was studied in an aqueous medium using ceric ammonium nitrate-nitric acid as the redox initiator. To optimize the reaction conditions for obtaining a maximum percent of grafting, the concentrations of methacryloxyethyl trimethylammonium chloride (DMC) monomer, ceric ammonium nitrate, and temperature were varied, and the effects on the grafting copolymerization were discussed. Under optimum conditions, a series of water-soluble monomers containing quaternary ammonium, such as methacryloxyethyl trimethylammonium chloride (DMC), DMAEMA˙C2H5Br, DMAEMA˙C4H9Br, DMAEMA˙C16H33Br, and DMAEMA˙C7H7Cl, were successfully grafted onto PVA. The resulting grafted PVA were characterized with IR, NMR, and viscosity measurements. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 2186–2191, 2005

Novozym-435-initiated reaction of cyclohexanones, nitrostyrenes, 4-nitrobenzaldehyde, and acetamide results in the formation of spirooxazines in a single step.

A facile and simple route for the direct preparation of substituted 3-methylcyclohex-2-enone via Aldol-Robinson cascade reaction of aldehydes and acetones catalyzed by the new catalytic system of L-lysine/imidazole in n-heptane with 0.5% water was reported. A variety of substrates can participate in the process efficiently. The merits of this method included inexpensive and easily available starting materials and catalyst, the good yield of products and the straightforward work-up.

A direct method to construct 3,4-dihydropyridin-2-ones by enzymatic condensation of aldehyde with cyanoacetamide and 1,3-dicarbonyl compounds was developed. One ring and four new bonds (two C–C, one C–N, one C C) were formed in one pot. And reaction conditions involving hydrolases, solvents, substrate molar ratios, and hydrolase loading were optimized. A series of new compounds based on the 3,4-dihydropyridin-2-one core were synthesized by the unprecedented three-component domino reaction.

An enzymatic method which combines D-aminoacylase catalyzed nitroaldol reaction and lipase PS-IM catalyzed acyl resolution reaction was constructed to obtain optically pure β-nitroalcohols in organic media under mild conditions. A series of β-nitroalcohols were synthesized and then resolved, with excellent ee values (>95%) and yields mostly, giving enantiomerically pure acetate and alcohol of the opposite configuration simultaneously.

A simple, efficient and eco-friendly route has been developed for the synthesis of β-mercapto diketones via a multicomponent reaction of an aldehyde, acetylacetone and thiol in water. This methodology affords a number of β-mercapto diketone derivatives in moderate to good yields.

Hantzsch-type reaction of 1,3-dicarbonyl compounds with aromatic and aliphatic aldehydes proceeds smoothly in the presence of Candida antarctica lipase-B using acetamide as a nitrogen source.

A series of new, substituted 2,3-dihydropyran derivatives were synthesized by one-pot, three-component reactions of aldehydes, 1,3-dicarbonyl derivatives, and vinyl ethers catalyzed by ethylenediamine diacetate (EDDA) under solvent-free conditions. This new, simple, and efficient, solvent-free, one-pot approach to the substituted 2,3-dihydropyran scaffold starting from simple substrates was found to take place directly.

Acidic ionic liquid N-methyl-2-pyrrolidonium dihydrogen phosphate [NMP]H2PO4 was prepared and used as efficient catalyst and reaction medium to synthesize β-alkoxyketones by the oxa-Michael addition reactions for the first time. The effect of anions and cations, amount of ionic liquid on the reaction was investigated. Various alcohols and phenols proceeded smoothly and led to corresponding β-alkoxyketones with high yields under mild reaction conditions, O-selectivity addition of aminoethanols was also achieved in this paper. Compared with traditional imidazolium ionic liquids, [NMP]H2PO4 gave the better results. The ionic liquid was stable and could be reused at least five times with a slight loss of activity.

Reaction of aromatic aldehyde hydrazones with azodicarboxylates in the presence of PPh3 allows an efficient and general access to 4-aminotriazolones of type (III).