Highly <i>Z</i>‑Selective and Enantioselective Ring-Opening/Cross-Metathesis Catalyzed by a Resolved Stereogenic-at-Ru Complex

The synthesis of a ruthenium complex that catalyzes <i>Z</i>-selective (up to 98% <i>Z</i>) asymmetric ring-opening/cross-metathesis with high enantioselectivity (up to 95% ee) is reported. The synthesis of the catalyst features the resolution of a chelating N-heterocyclic carbene complex by ligand substitution with a chiral carboxylate

Highly <i>Z</i>‑Selective and Enantioselective Ring-Opening/Cross-Metathesis Catalyzed by a Resolved Stereogenic-at-Ru Complex

The synthesis of a ruthenium complex that catalyzes <i>Z</i>-selective (up to 98% <i>Z</i>) asymmetric ring-opening/cross-metathesis with high enantioselectivity (up to 95% ee) is reported. The synthesis of the catalyst features the resolution of a chelating N-heterocyclic carbene complex by ligand substitution with a chiral carboxylate

Additional file 10: Figure S7. of Transcriptional analysis of sweet orange trees co-infected with ‘Candidatus Liberibacter asiaticus’ and mild or severe strains of Citrus tristeza virus

Expression of the actin gene estimated by RT-qPCR. HC, healthy control; B2/232, CTV-B2/CaLas-B232; B6/232, CTV-B6/CaLas-B232. Y-axis, Cq value. Bars with standard error of the mean expression level of the actin gene with three technical replicates for each biological replicate. (PDF 56 kb

Le Courrier

30 janvier 18391839/01/30 (N30)

Effect of Double-Bond Substituents on the Rate of Cyclization of α‑Carbomethoxyhex-5-enyl Radicals

Rate constants have been calculated, and compared with experimental results, for the cyclizations of 1-carbomethoxy-1-methyl-5-hexenyl radicals (<b>2</b>) with various substituents on C6. The calculations have been done by DFT at the B3LYP/6-311++G** level of theory. They show considerable interaction between C5 and the radical centers even in the ground state of all of the radicals <b>2</b>. Experimentally, the radicals have been generated by H^• transfer to the corresponding acrylate esters <b>1</b> and the yields of cyclized products compared to the calculated rate constants. (The “cyclized products” include those from cyclohydrogenation, <b>4</b>, and those from cycloisomerization, <b>9</b>.) Two phenyl substituents on C6 (<b>2i</b>), or a phenyl and a methyl substituent (<b>2g</b>, <b>2h</b>), increase the rate of cyclization, but a <i>single</i> phenyl substituent on C6 produces a <i>greater</i> increase. The calculations show that the two phenyl substituents are twisted in the transition state for cyclization, while a single phenyl substituent remains flat in that transition state. A methyl substituent on C6 along with a single phenyl causes the phenyl to twist in the transition state and decreases the rate constant for cyclization below that of the H/Ph-substituted <b>2e</b>, <b>2f</b>

Pd-Catalyzed Cyanation of a Bromoaryl Carboxylate En Route to Etrumadenant: Robust Process with Low Catalyst Loading Enabled by Preactivation

Palladium-catalyzed cyanation of aryl bromides is a powerful approach to install a functional group commonly found in active pharmaceutical ingredients starting from readily available precursors. The development of a robust cyanation of a bromo benzoic acid to generate an intermediate en route to etrumadenant is described. Full conversion with catalyst loading as low as 0.13 mol % was enabled by study of the catalyst preactivation step, which was affected by trace water levels. Details of the scale-up of this process to the hundred-kilogram batch size are included

<i>Xylella fastidiosa</i> isolates from Costa Rica.

a<p>Isolates previously published in Montero-Astúa et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0015488#pone.0015488-MonteroAsta2" target="_blank">[26]</a>.</p

Multi-Locus Sequence Typing (MLST) of 24 isolates from Costa Rica, together with data from 86 US isolates of <i>X. fastidiosa</i> subsp. <i>fastidiosa</i>, 21 US isolates of <i>X. fastidiosa</i> subsp. <i>sandyi</i>, plus representative data from <i>X. fastidiosa</i> subsp. <i>multiplex</i> and <i>X. fastidiosa</i> subsp. <i>pauca</i>.

1<p>For details of the MLST scheme see Yuan et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0015488#pone.0015488-Yuan1" target="_blank">[16]</a>.</p>2<p>Alleles with a 30 bp deletion.</p>3<p>Data from Yuan et al. <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0015488#pone.0015488-Yuan1" target="_blank">[16]</a>, except isolate LIQ0090 (ST39) (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0015488#s3" target="_blank">Methods</a>).</p>4<p>Recombinant allele, hence ST4 was not included in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0015488#pone-0015488-g002" target="_blank">Figure 2</a>.</p><p>The listed isolates were used to create <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0015488#pone-0015488-g002" target="_blank">Figure 2</a>.</p

Maximum likelihood phylogeny of <i>X. fastidiosa</i> showing U.S. <i>X. fastidiosa</i> subsp. <i>fastidiosa</i> sequence types (STs) nested within the Costa Rican STs.

<p>The circle encompasses all <i>X. fastidiosa</i> subsp. <i>fastidiosa</i> STs. The other subspecies are named on their ancestral branch. All unique STs are shown from 83 U.S. and 24 Costa Rican (CR) samples of subsp. <i>fastidiosa</i> and 21 US samples of subsp. <i>sandyi</i>. The number of isolates/ST is shown by xN. All CR isolates were from coffee except 3 from grape (designated by “grp”). <i>X. fastidiosa</i> subspp. <i>multiplex</i> and <i>pauca</i> are represented by a sample of sequence types (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0015488#pone-0015488-t001" target="_blank">Table 1</a>). All bootstrap values >80% are shown and the scale bar defines 1% sequence divergence.</p

Comparison of Temecula-1 and M23 <i>X. fastidiosa</i> genomes.

1<p>see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0015488#pone-0015488-t003" target="_blank">Table 3</a>.</p><p>“Variable” regions of the aligned genomes were regions with >1% sequence divergence (see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0015488#s3" target="_blank">Methods</a>). All other regions were classified as “Constant”. Variable regions were further classified into four subgroups: Recombination-M23 and Recombination-Tem (evidence of recombination of <i>X. fastidiosa</i> subsp. <i>multiplex</i> into M23 and Temecula-1 respectively); Duplicate Associated (at least one other copy of the region present in the genomes); and Other (unique variable sequence of unknown origin). Large Indels (>400 bp) were also recorded.</p