A novel Pd-catalysed oxidative coupling between benzoic acids and vinylarenes or acrylates to furnish isocoumarins and phthalides is reported. The reaction proceeds smoothly in molten tetrabutylammonium acetate via a selective CÀ H bond activation, with very low percentage of ligand-free palladium acetate as the catalyst, under atmospheric pressure of oxygen. Sub-stoichiometric amount of copper acetate is also required as a reoxidant for the palladium.
A significant area of study and upgrading for increasing sensitivity and general performances of matrix-assisted laser-desorption ionization (MALDI) mass spectrometry (MS) is related to matrix design. Several efforts have been made to address the challenge of low-mass-region interference-free for metabolomics analysis and specifically for lipidomics. To this aim, rationally designed matrices as 4-chloro-α-cyanocinnamic acid (ClCCA) were introduced and reported to provide enhanced analytical performances. We have taken this rational design one step further by developing and optimizing new MALDI matrices with a range of modifications on the CHCA core, involving different functionalities and substituents. Of particular interest was the understanding of the electron-withdrawing (e.g., nitro-) or donating (e.g., methoxy-) effects along with the extent of conjugation on the ionization efficiency. In the present work, ten matrices were designed on a reasonable basis, synthesized, and characterized by NMR and UV spectroscopies and laser desorption ionization. With the assistance of these putative MALDI matrices, samples containing phospholipids (PL), and neutral di-/tri-acylglycerols (DAG, TAG) were investigated using milk, fish, blood, and human plasma extracts. In comparison with CHCA and ClCCA, four of them, viz. [(2E,4E)-2-cyano-5-(4-methoxyphenyl)penta-2,4-dienoic acid] (1), [(2E,4E)-2-cyano-5-(4-nitrophenyl)penta-2,4-dienoic acid] (2), [(E)-2-cyano-3-(6-methoxynaphthalen-2-yl)acrylic acid] (6) and [(E)-2-cyano-3-(naphthalen-2-yl)acrylic acid] (7) displayed good to even excellent performances as MALDI matrices in terms of ionization capability, interference-free spectra, S/N ratio, and reproducibility. Especially compound 7 (cyano naphthyl acrylic acid, CNAA) was the election matrix for PL analysis and matrix 2 (cyano nitrophenyl dienoic acid, CNDA) for neutral lipids such as DAG and TAG in positive ion mode.
For the first time, secondary steel slag, the material directly coming from ladle treatments, is used as a catalyst for the biodiesel production without undergoing any preliminary chemical or thermal modifications. Catalytic material 1, which has been pre-ground to sizes below 230 mesh, has been characterized for the surface textural properties and used as a catalyst in the transesterification of triglycerides of soybean oil to produce biodiesel. Reaction conditions were optimized by DOE method, revealing no interdependence between reaction parameters and results, and showed a catalytic activity comparable with that of an analogous slag-deriving catalyst reported in the literature.
Soybean is largely cultivated worldwide providing high amounts of proteins and oil for food and feed, and isoflavones for nutraceutical uses. The increasing interest in agroforestry practices for improving carbon sequestration and mitigating climate changes suggests the need to assess soybean response to variations of light availability and direction. A two-year pot trial was carried out at Legnaro (NE Italy) in order to mimic the response of the soybean var. Sponsor to contrasting light orientation (east or west) by artificial shading, associated or not with mechanical leaf damage, in terms of protein accumulation, total cotyledon isoflavone concentration (TCIC) and isoflavone profile. Here, we demonstrate that a different intensity of the isoflavone metabolism exists in response to lighting conditions, with higher TCIC and slightly increased seed crude proteins in plants lighted from the east (morning time) and after mechanical leaf damage. The isoflavone profile was not changed, but low temperatures and high rainfall during seed filling (1st year) were associated with increased accumulation of medium-high molecular weight (MW) forms (i.e., glycosyls and malonyls), while high temperatures and low rainfall (2nd year) with increased accumulation of medium-low MW forms (i.e., glycosyls and aglycones). It is concluded that within agroforestry systems, there is possibly a large scope for maximizing isoflavone accumulation by selecting the harvesting area in the neighboring of the east side of the tree alleys, with further improvements if a mild shoot stripping is applied before flowering.
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