Highly Selective and Reversible Chemosensor for Pd²⁺ Detected by Fluorescence, Colorimetry, and Test Paper

A “turn-on” fluorescent and colorimetric chemosensor (<b>RBS</b>) for Pd²⁺ has been designed and synthesized through introduction of sulfur as a ligand atom to Rhodamine B. <b>RBS</b> exhibits high selectivity (freedom from the interference of Hg²⁺in particular) and sensitivity toward Pd²⁺ with a detection limit as low as 2.4 nM. <b>RBS</b> is also a reversible sensor, and it can be made into test paper to detect Pd²⁺ in pure water. Compared to the chemosensors that introduced phosphorus to Rhodamine to detect Pd²⁺, <b>RBS</b> can be synthesized more simply and economically

DataSheet1_Design, synthesis, and insecticidal activity of a novel series of flupyrimin analogs bearing 1-aryl-1H-pyrazol-4-yl subunits.PDF

To discover new potential insecticides to protect agricultural crops from damage, a series of novel flupyrimin derivatives containing an arylpyrazole core were designed and synthesized. Their structures were confirmed by 1H NMR, 13C NMR, and HRMS. Bioassays indicated that the 31 compounds synthesized possessed excellent insecticidal activity against Plutella xylostella. Among these target compounds, the lethality of A3, B1-B6, D4, and D6 reached 100% at 400 μg/ml. Moreover, when the concentration dropped to 25 μg/ml, the insecticidal activities against the Plutella xylostella for compounds B2, B3, and B4 still reached more than 70%. The structure–activity relationship of the Plutella xylostella was discussed. The density functional theory analysis of flupyrimin and B4 was carried out to support the abovementioned structure–activity relationship. The possible binding modes between receptor and active groups in title compounds were also verified by docking simulation. These results provided new ideas for the development of these novel candidate insecticides in the future.</p

Enantioselective Conjugate Addition of 2‑Acetyl Azaarenes to β,β‑Disubstituted Nitroalkene for the Construction of All-Carbon Quaternary Stereocenters

The first highly enantioselective conjugate addition of 2-acetyl azaarenes to α-substituted-β-nitro­acrylates was successfully realized under mild conditions by a Ni­(II)-bisoxa­zoline complex, providing the desired adducts bearing an all-carbon quaternary stereocenter in high yield with excellent enantioselectivity. The products obtained in this system could be readily converted into optically active β^2,2-amino esters, succinates, lactones, and lactams

Concentrations used to determine the sensitivity of wild-type isolates and pyrimorph-resistant mutants of <i>Phytophthora capsici</i> to various fungicides.

a<p>Concentrations used to determine the sensitivity of <i>Phytophthora capsici</i> mutants with high pyrimorph resistance to dimethomorph, flumorph, and mandipropamid respectively.</p

Structure and site of the mutation in the <i>PcCesA3</i> gene associated with pyrimorph resistance.

<p>(A) Intron/exon structure of the <i>PcCesA3</i> gene. Numbers represent the size in base pairs. Point mutations in pyrimorph-resistant mutants (RF>50) and the predicted amino acid substitution in the mutant gene products are indicated. (B) Alignment of partial amino acid sequences of CesA3 in <i>P. capsici</i> (PcCesA3). Hd3, Hd11, Hx18, and Dz21 are wild-type isolates. R3-2, R3-3, and R11-1 are pyrimorph-resistant mutants. Mutations in pyrimorph-resistant mutants of <i>P. capsici</i> are indicated by asterisks.</p

Specificity of allele-specific PCR primers for detection of <i>Phytophthora capsici</i> mutants with high pyrimorph resistance.

<p>R3-2, R3-3, and R11-1 are mutants with high resistance to pyrimorph and were obtained by exposure to the fungicide on agar; isolates Hd3 and Hd11 are the corresponding parental isolates.</p

Fitness of pyrimorph-resistant mutants (mutant designations begin with the letter R) and the corresponding parental isolates of <i>Phytophthora capsici</i>^a.

a<p>Means in a column followed by the same letter are not significantly different at <i>p</i> = 0.05 according to Fisher’s least significant difference.</p>b<p>On carrot agar.</p>c<p>Lesion area and sporulation were determined on detached pepper leaves, and disease score was determined on growing pepper plants.</p>d<p>A disease severity scale of 0–5 was used: 0, no visible symptoms; 1, leaves slightly wilted with black lesions beginning to appear on stems or 10–29% of entire plant diseased; 2, 30–49% of entire plant diseased; 3, 50–69% of entire plant diseased; 4, 70–90% of entire plant diseased; 5, dead plant <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0056513#pone.0056513-Kim1" target="_blank">[37]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0056513#pone.0056513-Hartman1" target="_blank">[38]</a>.</p

Level and stability of pyrimorph resistance for the parental wild-type isolates and the resistant mutants of <i>Phytophthora capsici.</i>

a<p>Parent isolates were collected from the field locations. Mutants were obtained by mass selection on pyrimorph-amended medium.</p>b<p>EC₅₀ = effective concentration for 50% inhibition of mycelial growth at the 1^st transfer and the 10^th transfer.</p>c<p>RF = resistance factor, a ratio of EC₅₀ for a fungicide-resistant mutant relative to the EC₅₀ for the parental isolate.</p>d<p>FSC = the ratio of RF values at the 1^st and 10^th transfers.</p

Frequency distribution of EC₅₀ values of <i>Phytophthora capsici</i> for pyrimorph.

<p>A total of 226 isolates of <i>P. capsici</i> were collected from 40 locations in 24 provinces of China; the locations had never been treated with pyrimorph. EC₅₀ represents the effective concentration causing 50% inhibition of mycelial growth of <i>P. capsici</i>.</p

Mycelial growth of <i>Phytophthora capsici</i> isolates and mutants on PDA as affected by temperature.

<p>(A, B, C, D) Isolates designated R3-X, R11-X, R18-X, and Dz-X are mutants of Hd3, Hd11, and Hx18, respectively, and were obtained by consecutive transfers on medium amended with pyrimorph. Values are means and standard errors. Colony diameters (minus plug diameters) were measured after 4 days of growth.</p