Investigation of the Photo-Fries Rearrangements of Two 2-Naphthyl Alkanoates by Experiment and Theory. Comparison with the Acid-Catalyzed Reactions

A detailed investigation of the photochemistry of 2-naphthyl acetate (1a) and 2-naphthyl myristate (1b) has been conducted under a variety of conditions. Factors related to the reactions such as temperature and solvent type have been explored. The results, most easily interpreted by photo-Fries type processes, are contrasted with those from the Lewis-acid catalyzed (dark) Fries reactions of 1a. They are also compared to the predictions of semiempirical and ab initio calculations using 2-naphthyl propanoate (1c) and species derived from it as models. Unsuccessful triplet sensitization experiments with benzophenone and calculations point to the excited singlet states of 1 as the immediate precursor to the acyl/2-naphthoxy radical pairs that recombine to form keto intermediates 2, reform 1, or diffuse apart and eventually yield 2-naphthol (4); enolization of 2 results in the isolated rearrangement products, n-acyl-2-naphthols (n-3). Static and dynamic fluorescence studies provide some insights into the nature of the lysis process. Irradiation of a mixture of appropriately labeled derivatives of 1 led to none of the expected “cross-over” products, indicating that the intermediates 2 arise from recombination of radical pairs from the same parent molecule. Irradiation of 1b in ethanol and 1-octanol provides no evidence for the intermediacy of dodecylketene and supports out-of-cage mechanisms as the exclusive source of 4. There are indications of subtle solvent effects and a conformational dependence on the distribution of photoproducts

Comparisons of the intrumental, reconstructed (this study) and Gry et al. (2004) reconstructed AMO index on annual and 11-year moving average basis.

<p>(<b>A</b>) Annual comparison of instrumental AMO index <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0022740#pone.0022740-Enfield1" target="_blank">[4]</a> (blue line), the reconstructed proxy series from this study (black line), and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0022740#pone.0022740-Gray1" target="_blank">[20]</a> tree-ring based AMO reconstruction (red line). (<b>B–D</b>) The above three records smoothed with an 11-year low-pass filter. Red and blue shaded areas represent warm and cold AMO phases respectively. All series (A–D) were normalized by their means and standard deviations. (<b>E</b>) Sample depth in number of cores for the six tree-ring width chronologies.</p

Additional file 1: of Evaluation of the ocular surface characteristics and Demodex infestation in paediatric and adult blepharokeratoconjunctivitis

Raw data for BKC study. Clinical data of ocular surface characteristics in controls and BKC patients. (XLSX 17 kb

Additional file 1 of Assessment of the efficiency of synergistic photocatalysis on penicillin G biodegradation by whole cell Paracoccus sp

Additional file 1: Table S1. Degradation capability of Penicillin G by different strain species as reported from previous literatures and this study. Fig. S1a-c: Structure of the identified metabolites of peak Nos. 2 (a), 3 (a), 4 (b), and 5 (c) by LC–MS analysis. Peak Nos. 2 and 3 in HPLC: Potassium 2-(carboxy(2-phenylacetamido)methyl)-5,5-dimethylthiazolidine-4-carboxylate and potassium 2-(4-carboxy-5,5-dimethylthiazolidin-2-yl)-2-(2-phenylacetamido) acetate. Peak No. 4 in HPLC: Phenylacetic acid. Peak No. 5 in HPLC: Mixture of two isomers, 2-(amino(carboxyl)methyl)-5,5-dimethylthiazolidine-4-carboxylic acid. Fig. S2a-b: 1H NMR (a) and 13C NMR (b) spectra of potassium 2-(carboxy(2-phenylacetamido)methyl)-5,5-dimethylthiazolidine-4-carboxylate and potassium 2-(4-carboxy-5,5-dimethylthiazolidin-2-yl)-2-(2-phenylacetamido) acetate. 1H NMR (500 MHz, D2O) δ:7.34–7.45 (m, 10H); 5.07–5.06 (d, J = 3 Hz, 1H); 5.05–5.06 (d, J = 6 Hz, 1H); 4.79–4.78 (d, J = 3 Hz, 2H), 4.25–4.24 (d, J = 6 Hz, 1H); 3.81–3.80 (d, J = 4.0 Hz, 2H); 3.72–3.70 (d, J = 12 Hz, 1H); 3.43–3.42 (d, J = 3.5 Hz, 2H); 1.57 (s, 3H); 1.51 (s, 3H); 1.23 (s,3H); 1.05 (s, 3H).13C NMR (125 MHz, D2O) δ:176.17, 175.58, 175.24, 174.93, 174.86, 174.30, 135.01, 134.50, 129.65(2C), 129.49(2C), 129.27(2C), 129.04(2C), 127.61, 127.42, 75.84, 75.28, 67.00, 66.02, 60.01, 58.61, 58.45, 55.24, 42.51, 42.46, 27.98, 27.75, 26.75, 26.33. LC–MS (m/z): 391.3[M + 1]+ (cald. For C16H19KN2O5S, 390.1), 353.2[M` + 1]+ (cald for C16H20N2O5S, 352.1). Fig. S3a-b: 1H NMR (a) and 13C NMR (b) spectra of phenylacetic acid. 1H NMR (500 MHz, D2O) δppm: 7.42–7.32 (m, 5H); 3.73 (s, 2H).13CNMR (125 MHz, D2O) δppm: 177.01, 134.17, 129.38(2C), 128.79(2C), 127.27, 40.54. LC–MS (m/z): 137.3[M + 1]+ (cald. For C8H8O2, 136.05). Fig. S4a-b: 1H NMR (a) and 13C NMR (b) spectra of 5,5-dimethylthiazolidine. 1H NMR (500 MHz, D2O) δ: 5.06–5.05 (d, J = 4.5 Hz, 1H); 4.85–4.83 (d, J = 10.0 Hz, 1H); 3.97–3.96 (d, J = 4.0 Hz, 1H); 3.64–3.62 (d, J = 10.0 Hz, 1H); 3.56 (s, 2H); 3.47 (s, 1H); 3.19 (s,1H); 1.45 (s, 3H); 1.44 (s, 3H); 1.19 (s, 3H); 1.13(s, 3H). 13C NMR (125 MHz, D2O) δ: 176.34, 174.38, 171.85, 171.20, 74.47, 74.00, 63.59, 63.29, 59.31, 58.68, 56.80, 56.39, 29.29, 26.06, 26.02, 25.94. LC–MS (m/z): 235.1 [M + 1]+ (cald for C8H14N2O4S, 234.07)

Amino Acid Bound Surfactants: A New Synthetic Family of Polymeric Monoliths Opening Up Possibilities for Chiral Separations in Capillary Electrochromatography

By combining a novel chiral amino-acid surfactant containing an acryloyl amide tail, a carbamate linker, and a leucine headgroup of different chain lengths with a conventional cross-linker and a polymerization technique, a new “one-pot” synthesis for the generation of amino-acid based polymeric monolith is realized. The method promises to open up the discovery of an amino-acid based polymeric monolith for chiral separations in capillary electrochromatography (CEC). The possibility of enhanced chemoselectivity for simultaneous separation of ephedrine and pseudoephedrine containing multiple chiral centers and the potential use of this amino-acid surfactant bound column for CEC and CEC coupled to mass spectrometric detection are demonstrated

Map of correlation between annual mean precipitable water and annual AMO index (1948–2007) across northeast Asia.

<p>Country boundaries for Russia, Mongolia, and northeast China are shown on the map. It is plotted by the NOAA/ESRL Physical Science Division, Boulder Colorado (<a href="http://www.esrl.noaa.gov" target="_blank">http://www.esrl.noaa.gov</a>). Letters on the map represent different tree-ring sampling sites: <b>A</b> – Zhigansk, <b>B</b> –Khotugn, <b>C</b> – Tschita, <b>D</b> – Taksimo, <b>E</b> – Mangui, <b>F</b> – Mengkeshan. Triangles, circles, and squares represent sampling sites, PDSI points, and weather stations, respectively. Differents colors represent different correlation coefficients marked as the legend at the bottom of the map. The figure on a contour represents the correlation coefficient of this contour.</p

Data_Sheet_1_Radial Growth of Trees Rather Than Shrubs in Boreal Forests Is Inhibited by Drought.PDF

Of all forest biomes, boreal forests are experiencing the most significant warming. Drought caused by warming has a dramatic impact on species in boreal forests. However, little is known about whether the growth of trees and shrubs in boreal forests responds consistently to warming and drought. We obtained the tree-ring width data of 308 trees (Larix gmelinii and Pinus sylvestris var. mongolica) and 133 shrubs (Pinus pumila) from 26 sites in northeastern China. According to the climate data from 1950 to 2014, we determined three extreme drought years (1954, 1967, and 2008). The response difference of radial growth of trees and shrubs in boreal forests to drought was compared using resilience index, moving correlation and response analysis. The results showed that high temperature (mean and maximum temperature) in previous and current growing seasons promoted the growth of P. pumila, but inhibited the growth of trees. On the contrary, wetter conditions (higher PDSI) promoted tree growth but were not conducive to P. pumila growth in high latitudes. Moving correlation analysis showed similar results. In addition, water deficit was more likely to inhibit P. pumila growth in low latitudes. The drought resistance of P. pumila was stronger than that of L. gmelinii and P. sylvestris var. mongolica. Therefore, the growth loss and recovery time of P. pumila during drought was less than those of trees. We concluded that L. gmelinii and P. sylvestris var. mongolica are more prone to growth decline than P. pumila after the drought caused by climate warming. In the future climate warming, shrub growth may benefit more than trees. Our findings are of great significance in predicting the future changes in ecosystem composition and species distribution dynamics in extreme climate susceptible areas.</p

Self-Adhesive Dry Ionic Conductors Based on Supramolecular Deep Eutectic Polymers

Ionic conductors have promising applications in the field of flexible electronics, but they usually suffer from weak bonding to substrates (<0.3 MPa), leading to large interfacial impedances or detachment under repeated deformation. Here, a supramolecular deep eutectic polymer synthesized by in situ photopolymerization of a polymerizable deep eutectic solvent monomer is proposed as a self-adhesive dry ionic conductor (SADIC). The SADICs obtained are rich in dynamic hydrogen bonding and ions, which can instantly form various interfacial interactions and firmly adhere to substrates and maintain good mechanical robustness. Notably, the maximum adhesion strength is up to ∼3.5 MPa (on indium tin oxide (ITO) glass). Furthermore, the SADICs also show other comprehensive properties such as high transparency, tunable stretchability, favorable conductivity, and excellent mechanical and electrical self-healing capabilities. As a demonstration, the SADIC can be used as a durably self-adhesive ionic skin for volume change and deformation monitoring. These findings provide a promising strategy for improving device integration and enhancing the performance of flexible electronics

Comparison of PDSI for the warm and cold AMO phases at six nearby sampling sites.

<p>Comparison of PDSI for the warm and cold AMO phases at six nearby sampling sites.</p

Multi-taper method spectrums for this proxy series from 1564–2007 (A) and the tree-ring AMO reconstruction from Atlantic rim [<b>20</b>] (B).

<p>Significance was tested at three levels (99%, 95% and 90%) against a red-noise background. Digital values are the significant periods at 99% confidence level.</p