The Other Press, January 5, 1990

<p>The crude earthworm extract catalysed domino reactions for the synthesis of coumarin derivatives.</p

Atmospheric Oxidation of Furan and Methyl-Substituted Furans Initiated by Hydroxyl Radicals

The atmospheric oxidation mechanism of furan and methylfurans (MFs) initiated by OH radicals is studied using high-level quantum chemistry and kinetic calculations. The reaction starts mainly with OH addition to the C2/C5-position, forming highly chemically activated adduct radical R2*/R5*, which would either be stabilized by collision or promptly isomerize to R2B*/R5B* by breaking the C2-O/C5-O bond and then isomerize to other conformers of R2B/R5B by internal rotations. Under the atmospheric conditions, the ring-retaining radical R2/R5 would recombine with O₂ and be converted to a 5-hydroxy-2-furanone compound and a compound containing epoxide, ester, and carbonyl functional groups, while the ring-opening radicals R2B/R5B would react with O₂ and form unsaturated 1,4-dicarbonyl compounds. RRKM-ME calculations on the fate of R2*/R5* from the addition of OH and furans predict that the fractions of R2B/R5B formation, i.e., the molar yields of the corresponding dicarbonyl compounds, are 0.73, 0.43, 0.26, 0.07, and 0.28 for furan, 2-MF, 3-MF, 2,3-DMF, and 2,5-DMF, respectively, at 298 K and 760 Torr when using the RHF-UCCSD­(T)-F12a/cc-pVDZ-F12 reaction energies and barrier heights. The predicted yields for dicarbonyl compounds agree reasonably with recent experimental measurements. Calculations here also suggest high yields of ring-retaining 5-hydroxy-2-furanone compounds, which might deserve further study

Synthesis of 2,3-Dialkylated Tartaric Acid Esters via Visible Light Photoredox-Catalyzed Reductive Dimerization of α‑Ketoesters

A mild transition-metal-free protocol to prepare 2,3-dialkylated tartaric acid esters has been developed by taking advantage of a visible light photoredox-catalyzed reductive dimerization of α-ketoesters with a combination of an organic dye photocatalyst and a Hantzsch-type 1,4-dihydropyridine hydrogen donor. A broad range of functional groups including cyclopropane, alkene, alkyne, 4-methoxybenzyl ether, acetal, silyl ether, carbamate, cyclic ether, cyclic thioether, bromoalkane, and <i>N</i>-alkoxyphthalimide are well-compatible. By employing the visible light photoredox-catalyzed reductive coupling and the subsequent optical resolution, both enantioenriched diastereomers of 2,3-dialkylated tartaric acid could be acquired conveniently

Synthesis of 2,3-Dialkylated Tartaric Acid Esters via Visible Light Photoredox-Catalyzed Reductive Dimerization of α‑Ketoesters

A mild transition-metal-free protocol to prepare 2,3-dialkylated tartaric acid esters has been developed by taking advantage of a visible light photoredox-catalyzed reductive dimerization of α-ketoesters with a combination of an organic dye photocatalyst and a Hantzsch-type 1,4-dihydropyridine hydrogen donor. A broad range of functional groups including cyclopropane, alkene, alkyne, 4-methoxybenzyl ether, acetal, silyl ether, carbamate, cyclic ether, cyclic thioether, bromoalkane, and <i>N</i>-alkoxyphthalimide are well-compatible. By employing the visible light photoredox-catalyzed reductive coupling and the subsequent optical resolution, both enantioenriched diastereomers of 2,3-dialkylated tartaric acid could be acquired conveniently

Relationship between RELN mRNA expression level and clinicopathological features in 40 primary ESCC samples.

<p>RELN expression means mRNA expression in human ESCC tissues described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0031802#pone-0031802-g006" target="_blank">Figure 6</a>.</p><p>Student's <i>t</i> test was used to examine the difference of RELN mRNA levels.</p

Snail regulates RELN expression in ESCC cells.

<p><b>A&B</b>: Snail protein was increased (<b>A</b>) and RELN mRNA was decreased (<b>B</b>) in a time-dependent manner after 5 ng/ml TGF-β1 treatment in KYSE-510 cells. β-actin served as the loading control in Western blot. <b>C</b>: RT-qPCR analysis showing that Snail down-regulates RELN mRNA expression in KYSE30 and KYSE-510 cells. Data represent the mean ± SD of triplicate experiments. *, <i>p</i><0.05. <b>D</b>: Snail down-regulates RELN promoter activity in KYSE-30 and KYSE510 cells in a dose-dependent manner. Data represent the mean ± SD of triplicate experiments. <b>E</b>: Snail binds to the RELN promoter after TGF-β1 treatment in KYSE-510 cells. Schematic representation of RELN promoter region, +1 = transcription start site (<i>left</i>). ChIP assay was carried out by using a rabbit anti-Snail antibody or the rabbit IgG as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0031802#s4" target="_blank"><i>Materials and Methods</i></a>. The presence of sequences corresponding to RELN promoters and β-actin were analyzed, and β-actin served as the negative control (<i>right</i>).</p

TGF-β1 suppressed RELN expression and transient transfection of Reelin blocked TGF-β1-induced cell migration.

<p><b>A</b>: RT-PCR analysis showing RELN mRNA expression in eight ESCC cell lines, GAPDH was used as an internal control. <b>B</b>: Reelin protein was localized in cytoplasm in KYSE-510 cells by immunostaining. Mouse IgG was used as isotype negative control. <i>Scale bar</i>: 20 µm. <b>C</b>: KYSE-510 cells were treated with 5 ng/ml TGF-β1, RELN mRNA expression was examined by RT-PCR, and GAPDH was used as an internal control. <b>D</b>: Western blot for Reelin protein using whole cell extract at 48 hours after reelin (pCrl) transfection in KYSE-30 cells. β-actin served as the loading control. <b>E</b>: 5 ng/ml TGF-β1 was added in media for 24 hours after pCrl transfection and Transwell assay was performed at 48 hours after transfection (<i>left</i>). The bar graph shows the relative number of migrated cells from three independent experiments (<i>right</i>). Data represent the mean ± SD of triplicate experiments. *, <i>p</i><0.05.</p

TGF-β1 treatment decreased RELN transcriptional activity, but did not affect RELN mRNA stability.

<p><b>A</b>: TGF-β1 down-regulated the RELN promoter activity. KYSE-510 cells were transiently transfected with pGL3-basic and the RELN promoter-luciferase construct, and simultaneously treated by 5 ng/ml TGF-β1 at 24 hours after transfection. Data represent the mean ± SD of triplicate experiments. *, <i>p</i><0.05. B. KYSE-510 cells were treated with or without 5 ng/ml TGF-β1 for 1 hour followed by actinomycin D (<i>Act D</i>; 5 µg/ml) treatment for the indicated time. RELN mRNA level was measured by RT-qPCR (<i>left</i>) and plotted on a logarithmic scale to calculate the time required for each mRNA to reach one-half of its initial abundance (<i>right</i>). Dotted line represents RELN mRNA expression after TGF-β1 treatment and straight line represents RELN mRNA expression of untreated control.</p

Role of Reelin in cell migration.

<p><b>A</b>: RT-PCR analysis showing RELN mRNA level in RELN and scramble siRNAs transfected cells, and GAPDH was used as an internal control. <b>B</b>: Transwell assay showing that RELN knockdown increased cell migration. Cells were stained with crystal violet (<i>left</i>). The bar graph shows the relative number of migrated cells from three independent experiments (mean+SE, <i>right</i>). *, p<0.05. <b>C</b>: RT-PCR analysis showing RELN mRNA level in RELN shRNA and scramble clones. <b>D</b>: Transwell assay showing cell migration of the RELN shRNA and scramble clones. Cells were stained with crystal violet (<i>top</i>). The bar graph shows the relative number of migrated cells from three independent experiments (mean+SE, <i>bottom</i>). *, <i>p</i><0.05. <b>E</b>: RT-qPCR showing the mRNA expression of some EMT markers in RELN shRNA and scramble clones. Data represent the mean ± SD of triplicate experiments.</p

Structure of the Mixed Aggregates between a Chiral Lithium Amide and Phenyllithium or Vinyllithium

The structures, in THF, of 1:1 mixed aggregates of phenyllithium or vinyllithium with a chiral lithium amide derived from a 3-aminopyrrolidine are proposed on the basis of a multinuclear (¹H, ⁶Li, ¹³C) NMR spectroscopic and DFT theoretical studies. In both cases, the lithium amide adopts an azanorbornyl-like folding and establishes stable coordinations with the C sp² reactants, leading to rigid complexes that are expected to be at the origin of the inductions observed for the alcohols resulting from the condensation of these mixed aggregates on <i>ortho</i>-tolualdehyde