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A novel strategy for developing a hypochlorite fluorescent probe by exploiting the ortho-vinylhydropyridine-assisted amido-to-nitroso oxidation reaction is presented.

In the present study, soy protein isolate was modified by tannic acid and used as a stabilizer for Pickering emulsions loaded with aroma compounds. The nanoparticles with tannic acid concentrations above 2 mg/mL were found to show great antioxidant properties. Essential oils, aroma compounds, and flavours can be stabilized by nanoparticles to form Pickering emulsions with a droplet diameter of600 nm. E-nose analysis shows that nanoparticles provide outstanding protective functionalities for the 6 essential oils at 37 °C for 30 days. Further study of limonene and citral indicates that the nanoparticles afford nearly 60% protection against loss with a tannic acid concentration of 10 mg/mL. Furthermore, the nanoparticles also maintain the aroma of the beverages and lengthen the five-day shelf life. Overall, this research provides a sustainable, low-cost, and quickly prepared stabilizer for aroma compounds in foods.

We developed a new chromogenic and fluorescent "off–on" 1,8-naphthalimide-derivated chemosensor 1 based on an F−-triggered desilylation reaction. It showed significant variations in UV/Visible absorption (510 nm) and fluorescence emission wavelength (570 nm) for selective detection of fluorides in tetrahydrofuran. Moreover, chemodosimeter 1-loaded test strips were successfully fabricated todetect fluorides efficiently.

A novel CH-controlled colorimetric probe based on anthracene carboximide was developed for the near-infrared detection of cyanide. The probe was constructed by attachment of a CHCN binding site to anthracene carboximide fluorophore, and it showed a significant visual change from yellow-green (535 nm) to deep violet (825 nm) with a larger redshift (≈290 nm) when interacting with cyanide. The C-H deprotonation sensing mechanism was confirmed by 1H NMR titration. Additionally, colorimetric test paper was conveniently used to detect cyanide in aqueous solutions. The near-infrared detection of cyanide by CH-controlled probes was founded for the first time.

A chemical sensor that can induce near-infrared red-shifted response represents a promising strategy for the design and development of anion probes. In this work, novel CH-controlled colorimetric probe 3 based on anthracene carboximide was developed for near-infrared detection of cyanide. Probe 3 consisted of CHCN binding site to anthracene carboximide fluorophore, and showed a significant visual change from yellow-green (535 nm) to deep violet (825 nm) with a larger redshift (≈ 290 nm) and fluorescence quenching at 480 nm and 520 nm upon interacting with cyanide. Job curves determined 1:1 binding stoichiometry of probe 3 with cyanide. Additonally, probe 3 detected cyanide ion conveniently in aqueous solution and could be reused after trifluoroacetic acid treatment. Colorimetric test paper was used to detect cyanide in aqueous solutions. The C–H deprotonation sensing mechanism was confirmed by 1H NMR titration. The near-infrared detection of cyanide by CH-controlled probes was founded for the first time.

A colorimetric anion sensor based on the activated C-H group is described, and the selective and reusable detection of cyanide using the sensor is demonstrated. The system uses bromine to block isomerization and trifluoromethyl-directed C-H regioselective functionalization for direct C-C bond formation between a fluorophore and 2-(pyridin-2-yl)acetonitrile. Thus, this system provides a new way to develop activated CH-based anion receptors.

A fluorescent and colorimetric cyanide sensor (4-Br) based on the activated C-H group to conscruct a FRET platform has been described for the first time, along with demonstration of selective and reversible detection of cyanides through it. The sensing mechanism of 4-Br is an integration of ICT and FRET mechanisms, based on the deprotonation of the activated C-H group. Importantly, it is suitable for fluorescence imaging of cyanides in living cell.

Herein we report the novel synthesis of nitrile-containing naphthalimide aryl ether derivatives via transition metal-free cyanide ion-promoted nucleophilic displacement of nitronaphthalimide with alcohols or phenols. The transformation involves a one-pot reaction, which is operationally simple and mild and bereft of transition metal catalysts. This work provides a novel route for the preparation of diaryl ether derivatives.

Kushui Rose (Rosa setate x Rosa rugosa, KR) is a distinctive Chinese rose variety. Its extracts, especially essential oil (EO), showed various biological activities. In this study, double molecular distillation was used to separate different fractions from KREO. GC-MS was used to detect the composition of volatile components in different fractions. The aroma analysis of different fractions was carried out by a professional sensory evaluation team. D1 (the light phase in the first stage) and R2 (the heavy phase in the second stage) showed better biological activities, with a lower IC50 value on antioxidant ability and a higher capacity for antimicrobial. Furthermore, D1 and R2 also effectively prevented the oxidation of sunflower oil. The antimicrobial mechanism was explored by relative conductivity, the content of protein and reducing sugar, and scanning electron microscopy on Escherichia coli. In all, molecular distillation could be considered an effective way to improve the aroma and biological activity for KREO.

A fluorescent and colorimetric anion sensor based on the activated C-H group has been developed, and its reusability and ability to selectively detect cyanides have been demonstrated. The system utilizes trifluoromethylcarbinol-directed C-H regioselective cyanomethylation for direct C-C bond formation between the fluorophore and acetonitrile. The present paper also describes a novel strategy for the enhancement of carbanion stability by a potential intramolecular C[double bond, length as m-dash]OH-C hydrogen bonding system, thus providing a new way to develop activated CH-based anion receptors.

A novel chromogenic and fluorogenic chromene-derived fluorescent probe 5 with a unique imine-controlled excited-state intramolecular proton transfer (ESIPT) mechanism was first developed to sense cyanides with excellent selectivity and high sensitivity in aqueous environments. Under the induction of cyanide, ESIPT occurs and the probe's structure changes from normal form (N) to tautomeric form 5՛ (T). Introduction of excess cyanide promotes final deprotonation of NH. 1H NMR titration experiments further supported the proposed mechanism. Interestingly, probe 5-based test strips were successfully fabricated to efficiently detect cyanides in practical application. In addition, probe 5 has great potential application for cyanide detection in food samples such as cassava flour and bitter almonds.

Dyes are indispensable in the textile industry and are very difficult to degrade due to the presence of two or more benzene rings in their structures. However, the purification of water resources is currently an urgent issue. In this study, a trichlorotriazine-derived calix[4]arene and 1,3,5-tris(4-aminophenyl) benzene were crosslinked to generate a calix[4]arene crosslinked polymer that can serve as a highly efficient adsorbent for separating cationic dyes from water. This research provides evidence for the efficiency of the polymer to adsorb various organic micropollutants in water via batch adsorption experiments. In particular, this polymer exhibited a removal efficiency over 99.6% and 99.4% for methylene blue and toluidine blue within 5 min, respectively. The kinetic results showed that the adsorption process of this polymer for organic dyes could be described with quasi-second-order models, and Langmuir isotherm adsorption models demonstrated that the maximum equilibrium adsorption capacity for methylene blue and toluidine blue was reached to 1806.82 and 2161.32 mg g−1, respectively. These observations suggest that the adsorption is mainly dependent on the electrostatic interactions, π−π interactions, and hydrogen bonding between the polymer and the organic dyes. Furthermore, the adsorption capacities of the adsorbent were maintained at high levels after five cycles. Its excellent adsorption capability and recyclability make this polymer a promising candidate for potential applications in water purification.

Highly selective and sensitive fluorescent and colorimetric cis/trans isomers 3 were rationally designed and investigated for the fast detection and visualization of cyanide ions (TBACN and NaCN) via CN-promoted Si–O cleavage in aqueous solution and in the solid state. The CN-promoted desilylation induced significant variations of the optical signals of cis- and trans-3, which mainly depend upon the steric arrangement of the Si–O group in relation to the π-extended system.

A novel dual-site controlled intramolecular charge transfer–photoinduced electron transfer–Fluorescence resonance energy transfer (ICT–PET–FRET) probe 6b and its reference ICT–FRET probe 6a were designed and synthesized. The probes show high selective fluorescent and colorimetric sensing for cyanide ions. The NH and CH groups connected by the π-extension framework in probe 6b were simultaneously employed as the two sensing sites and controlled the fluorescence of naphthalimide unites by PET, ICT followed by the corresponding FRET processes between coumarin and naphthalimide fluorophores.

A specific recognition of CN− by activation of latent intramolecular Br⋯H C hydrogen bonding was developed for the first time. The visually colorimetric and “turn-on” fluorescent detection with large stokes shift (ΔF ≈ 137 nm) can be attributed to the formation of semi-rigid hydrogen-bonded complexes by intermolecular hydrogen bonding followed by activated intramolecular Br⋯H C hydrogen bonding.

A fast photochemical C–C bond formation between cyclic ethers/acetals and olefins using di-tert-butyl peroxide (DTBP) was developed. This method provides easy access to 2-substituted cyclic ethers, and 2- or 4-substituted cyclic acetals. Acyl/formyl groups or diols can be obtained by the hydrolysis of the 2- or 4-substituted cyclic acetals, respectively. The reactions proceeded at room temperature and gave the expected products in good to excellent yields; efficient reactions were completed within 0.5 h at room temperature in >95% yield.

A new chromogenic and fluorescent “turn-on” chemodosimeter 3 was designed and synthesized by using a fluoride-sensitive self-immolative linker, in combination with the fluorescent dyes 7-hydroxy-4-trifluoromethyl coumarin. The chemodosimeter exhibited high selectivity and sensitivity toward fluoride anions through “turn-on” chromogenic and fluorogenic dual modes.

A new chemodosimeter for fluoride ions based on F(-) triggered dual Si-O bond cleavage of distyrylbenzenes derivatives was developed for the first time. Upon the addition of F(-) ions, the chemodosimeter (7) displayed apparent color changes from colorless to faint yellow, with a dramatic red-shift in the emission wavelength (~100 nm), and higher selectivity for fluoride over other common anions. With the aid of fluorescence measurements, the limit of detection could be as low as 89.8 nm. Using a 'dipstick' approach, chemodosimeter (7) might serve as a prototype device for fluorescent detecting F(-) without the need for any additional equipment. Copyright © 2015 John Wiley & Sons, Ltd.

Development of colorimetric sensors has emerged as an attractive strategy for cyanide detection owing to their unique advantages, including simple visual detection and economical nature. In this work, anthraquinone derivatives (3a-d) have been easily prepared via nucleophilic substitution of 1-chloro anthraquinone with substituted phenylacetonitriles, with only nitro-substituted anthraquinone 3d displaying colorimetric sensor capabilities. The sensor showed good selectivity, reversibility and reusability toward cyanide detection, as well as efficient naked-eye color change from colorless to blue-purple in a neutral aqueous medium. The deprotonation mechanism of CH was investigated by NMR spectroscopy and supported by DFT calculations. Furthermore, the sensor 3d was successfully loaded onto test strips as a convenient and efficient solid-state sensor for cyanide detection. It was utilized for cyanide detection in cassava flour and bitter almonds food samples, as well as displaying excellent performance in real-world water samples.

A simple “turn-on” colorimetric and fluorometric chemosensor, 3-nitro-1,8-naphthalimide derivative (1), was successfully developed for the light-up detection of CN− with high selectivity. The cyanide-induced nucleophilic substitution of hydrogen in nitro-controlled naphthalimide (1) to produce the anionic δH adducts, which can be further converted to cyanation-hydroxylation product 3, was first disclosed.

Herein we report a method for introducing a substituted aryl acetonitrile group at the C2 position of naphthalimide using trifluoromethyl as the directing group. The transformation is operationally simple, requires mild conditions and is highly regioselective, without the need for a transition metal (TM) catalyst. This work provides a novel route for preparing α-diaryl nitrile derivatives .

A novel fluorescent and colorimetric BODIPYchemosensor 1 based on activated C–H group was developed for the reversible and reusable selective sensing of cyanide ions. The chemosensor was able of detecting cyanide ions (CN−) in aqueous media (70% water, LOD ≈ 148 nM). In addition, test strips were easily fabricated with the chemosensor 1 for convenient and efficient detection of CN−. This article provides a novel way for enhancing carbanion stability by forming potential intramolecular CH⋯F(BF2) hydrogen bonding system. Thus this expand the activated CH-based strategy to BODIPY fluorophore for development of anion receptors.

A facile and efficient SNAr procedure involving the displacement of activated naphthalimide bromides with the anions of substituted aryl acetonitriles was developed for the preparation of α,α-aryl naphthalimide nitrile derivatives, which can be used as fluoride ion sensors and convenient precursors for the synthesis of aryl naphthalimide ketones based on fluoride-induced deprotonation followed by autoxidative decyanation.

A new fluorescent “turn-on” cyanide chemodosimeter 5 was developed for the first time based on the irreversible deprotonation/oxidation of the CH group followed by the reversible deprotonation of the NH group, with high selectivity and dramatic red-shifted absorption (≈263 nm). The photoinduced electron transfer (PET) is prevented by the irreversible process, which results in coplanar geometry between indole and naphthalimide causing enhancement of fluorescence.

A highly selective and reversible chemosensor for cyanide and pH detection was developed based on intramolecular NH⋯NH2 hydrogen bonding.

Poly(ethylene terephthalate) (PET) fabrics are currently dyed using disperse dyes at high temperatures and pressures because of their low dyeability, which implies the use of a large amount of energy and pressurized vessels that are unsuitable for safe operation. Simple irradiation with a commercially available germicidal lamp was applied to the PET fabrics using aqueous H2O2 and H2O2 + acrylic acid solutions at room temperature under air. A more than seven-fold increase in dyeability with cationic dyes was obtained at atmospheric pressure at reduced temperatures. For the first time, the increase in dyeability was observed only with H2O2 by a reaction with O2 in air. The increase in dyeability was attributed to the introduction of carboxylic acid groups on the fabric surface, which was confirmed by IR and UV spectroscopy and chemical reactions.

A microchannel reactor was used for suppressing undesirable side reactions in a photochemical reaction. A two-step photolysis, flavone (1) → flavanone (2) → salicylic acid (3b), was conducted in a microchannel reactor using a two-phase photolysis, that is, 1 and NaBH4 were dissolved in immiscible H2O and hexane, respectively, and photolyses were conducted at their interface. The two-step photolysis product 3b was obtained as a major product. In contrast, photolysis in homogeneous EtOH solution gave flavanol (4) as a major product. The thermal side reaction 2 → 4 was suppressed completely by the interface photolysis, and a greater than 25-fold increase was observed in the selectivity of 3b.

An efficient approach to the synthesis of 1-methylimidazo[4,5-b]pyridine derivatives 5–10 of biological interest has been developed. The key intermediate product 4 is obtained by cyclization of 2-amino-3-methylaminopyridine (3) with phenylacetic acid.

A radical C–C bond formation between olefins and alcohols proceeded efficiently by simple light irradiation at room temperature. The reaction proceeded in the presence of commercially available tBuOOtBu without using the harmful elements and/or compounds that have an unpleasant smell that are often used in conventional radical reactions. In addition, the reaction did not require photosensitizers or photocatalysts, which eliminated the time-consuming separation of sensitizers after the reaction, or the synthesis of photocatalysts as reported in previous procedures.

The crystal structure of 1-(2,6-dichloro-4-(trifluoromethyl)phenyl)-6-ethyl-1H-pyrazolo[3,4-b]pyridine-3-carbonitrile was obtained and determined by X-ray crystallography. The reaction mechanism of 5-amino-1-(2,6-dichloro-4-(trifluoromethyl)phenyl)-1H-pyrazole-3-carbonitrile with unsaturated carbonyl compounds was further proposed.

Novel heterocyclic enamine derivatives based on skeleton of neonicotinoids were designed and prepared by the substitution reaction between heterocyclic enamines with intermediates of neonicotinoids, which provides readily accessible neonicotinoid analogs for potential bioactivity assay.

Cell dedifferentiation, somatic embryogenesis, and cell wall regeneration are key steps in plant regeneration. In order to improve the efficiency of plant regeneration in cotton, we mapped genes related to cell morphogenesis. A total of 489 markers, including SSRs, PIPs, and sequence-specific markers related to cell dedifferentiation, somatic embryogenesis, and cell wall regeneration were developed. Only 19 markers showed polymorphism between parents of the mapping population upon high-resolution gel and SSCP analysis, and 21 polymorphic loci were generated. Thirteen loci were mapped on 9 cotton chromosomes, four of which were on Chr16. Seven of the 13 loci were mapped on the At sub-genome and six on the Dt sub-genome. This study provides an overview of the chromosome distribution of genes related to cell morphogenesis in cotton. The markers developed in this study will be useful in marker-assisted selection of better genotypes for plant regeneration in cotton.

Asymmetric hybrids between Gossypium hirsutum (YZ-1) and G. davidsonii were obtained by donor-recipient fusion. YZ-1 was considered the recipient and was pretreated with iodoacetamide (IOA), while G. davidsonii was considered the donor and was irradiated with ultraviolet (UV) before fusion. YZ-1 protoplasts stopped growth when treated with 0.5 mmol/L IOA for 20 min, and G. davidsonii protoplasts stopped growth when irradiated with 38.7 J/cm2 UV for 30 s. Asymmetric somatic hybrids were obtained by electrofusion between the separately treated protoplasts of the 2 species. The regenerated plants were identified by morphological, cytological, and molecular analysis. Most regenerated plants derived from fused protoplasts displayed new morphology; some were intermediate between the two parents and a few displayed recipient-like morphology. Chromosome numbers in these somatic hybrids mostly ranged from 40 to 73. The hybridity was confirmed by random amplified polymorphic DNA and simple sequence repeat analysis. Organelle DNA inheritance of the YZ-1 and G. davidsonii somatic hybrid was investigated by cleaved amplified polymorphism sequence and chloroplast simple sequence repeat analysis, which indicated that recombination and rearrangements might have occurred in some regions of mitochondrial and chloroplastic DNA. This is the first report of completely asymmetric hybrid production via donor-recipient fusion between G. hirsutum and G. davidsonii, which is a novel case in hybrid production following the symmetric fusion and asymmetric fusion based on UV irradiation in cotton.

We have developed a single-step synthesis of pyrazolopyridines and hydropyrazolopyridines by condensation 3-carbonitrile-5-aminopyrazole (1) with seven substituted α,β-unsaturated aldehydes in acid medium. Straightforward access to various pyrazolopyridines and hydropyrazolopyridines was achieved through disproportionation of initially formed pyrazolo Hantzsch dihydropyridines. All the pyrazolopyridines and hydropyrazolopyridines were well characterized by spectroscopic analyses.

We have developed a chromogenic and fluorescent chemodosimeter3, based on a novel anion-catalyzed intramolecular hydrogen transfer, which displayed drastic changes in UV-Vis absorption as well as fluorescence emission intensities showing selectively for F− over other anions.

A new chemodosimeter for fluoride ions based on F(-) triggered dual Si-O bond cleavage of distyrylbenzenes derivatives was developed for the first time. Upon the addition of F(-) ions, the chemodosimeter (7) displayed apparent color changes from colorless to faint yellow, with a dramatic red-shift in the emission wavelength (~100 nm), and higher selectivity for fluoride over other common anions. With the aid of fluorescence measurements, the limit of detection could be as low as 89.8 nm. Using a 'dipstick' approach, chemodosimeter (7) might serve as a prototype device for fluorescent detecting F(-) without the need for any additional equipment. Copyright © 2015 John WileySons, Ltd.

α,α-Aryl naphthalimide nitriles (III) are efficiently obtained by a SNAr procedure involving the displacement of activated naphthalimide bromides (I) with the anions of substituted aryl acetonitriles (II).

A highly selective and reversible chemosensor for cyanide and pH detection was developed based on intramolecular NH···NH2 hydrogen bonding.

Quantitative trait locus (QTL) mapping is an important method in marker-assisted selection breeding. Many studies on the QTLs focus on cotton fibre yield and quality; however, most are conducted at the DNA level, which may reveal null QTLs. Hence, QTL mapping based on transcriptome maps at the cDNA level is often more reliable. In this study, an interspecific transcriptome map of allotetraploid cotton was developed based on an F2 population (Emian22 × 3-79) by amplifying cDNA using EST-SSRs. The map was constructed using cDNA obtained from developing fibres at five days post anthesis (DPA). A total of 1270 EST-SSRs were screened for polymorphisms between the mapping parents. The resulting transcriptome linkage map contained 242 markers that were distributed in 32 linkage groups (26 chromosomes). The full length of this map is 1938.72 cM with a mean marker distance of 8.01 cM. The functions of some ESTs have been annotated by exploring homologous sequences. Some markers were related to the differentiation and elongation of cotton fibre, while most were related to the basic metabolism. This study demonstrates that constructing a transcriptome linkage map by amplifying cDNAs using EST-SSRs is a simple and practical method as well as a powerful tool to map eQTLs for fibre quality and other traits in cotton.

The cis- and trans-configurational isomers of 3 are designed and investigated as chemodosimeters for CN(-) ions for the first time. The cis-3 reveals a NIR absorbance at 717 nm (vs. trans-3, 620 nm), and such a configurational difference can be attributed to the acidity as well as position of the binding site (CH group). A probable sensing mechanism involving cyanide-driven carbanion electron-transfer oxidation is proposed.