Alfa grass lignin obtained by the acetic acid/formic acid/water CIMV pulping process was characterized by FTIR and (1)H, (13)C-(1)H 2D HSQC, and (31)P NMR spectroscopies. Lignin samples purified by further dissolution/precipitation or basic hydrolysis steps were also analyzed. The CIMV alfa lignin is a mixture of low molar mass compounds (M(n) = 1500 g/mol) of SGH type with β-O-4 ether bonds as the major interunit linkage. The crude lignin contains fatty acids and residual polysaccharides. It also contains large amounts of acetate and hydroxycinnamates, mostly in the γ-position of β-O-4 interunit linkages. Although partial acetylation induced by the process cannot be excluded, the absence of aromatic acetates and acetylated polysaccharides in crude lignin demonstrates the mildness of the process. By combining smooth alkaline hydrolysis and dissolution/precipitation steps to the CIMV pulping, it is possible to produce a purified lignin with a composition and a structure quite analogous to that of the native polymer in the plant.

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Samples of leaves, flowers and fruits of four browse species were collected from uplands in the province of León (northwestern Spain) at different sampling times (from spring till autumn). The browse species were Erica australis (Spanish heath), Cistus laurifolius (laurel-leaved rock rose), Quercus pyrenaica (hoary oak) and Rosa canina (wild dog rose). A large variability in chemical composition and in vitro digestibility and gas production kinetics was observed among species and among sampling times within each species. The ranking order of the browse plants according to their in vitro digestibility and gas production kinetics was R canina > Q pyrenaica > C laurifolius > E australis. In the leaves of R canina and Q pyrenaica, crude protein content, digestibility and parameters of gas production tended to decrease throughout the growing season (P < 0.05 in most cases), whereas cell wall contents followed the opposite trend. Seasonal variations were less pronounced in the other browse species. There were significant (P < 0.05) correlations between in vitro digestibility and chemical composition of the browse plants, positive with the crude protein content and negative with the fibre fractions.

Chemical composition and in vitro digestibility were determined in stems and leaves hand-separated from grasses and legumes obtained from the first and subsequent cuts of a permanent meadow. Grasses from the first cut were classified in four groups according to their stage of maturity: vegetative, boot, head-bloom and seed stage. Crude protein (CP) content was higher and neutral detergent fibre (NDF) content lower in legumes than in grasses, and in leaves than in stems. CP decreased and NDF increased with maturity in grasses. In general, legumes were more digestible than grasses. The digestibility of grasses harvested in the first cut decreased with increasing maturity. Leaves were more digestible than stems in legumes and grasses, although the relative difference between botanical parts was much larger in grasses than in legumes. The differences in digestibility between leaves and stems became more pronounced with increasing maturity, especially in terms of cell wall digestibility. As for forage quality, early cutting of permanent meadows would be recommended, so that grasses are harvested before they reach an advanced stage of maturity.

Herein, we report the Pd-catalyzed regioselective direct arylation of heteroarenes in which benzenesulfonyl chlorides are used as coupling partners through a desulfitative cross-coupling that can be performed in diethyl carbonate (DEC) or cyclopentyl methyl ether (CPME) as green and renewable solvents or even in neat conditions instead of dioxane or dimethylacetamide (DMA). Under these solvent conditions, the reaction proceeds with a wide range of heteroarenes. C2- or C5-arylated products were obtained with furan and pyrrole derivatives. Benzofuran was also arylated regioselectively at the C2-position, whereas the reaction proceeds selectively at the C3- or C4-positions if thiophenes and benzothiophenes are used. Moreover, in some cases, especially with 1-methylindole, solvent-free conditions afforded better regioselectivities and/or yields than the reaction performed in the presence of solvents.

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The current study was carried out to evaluate the effect of pretreatment and co-treatment with a newly synthesized coumarin hydrazone, (E)-4-hydroxy-N′-(1-(3-oxo-3H-benzo[f]chromen-2-yl)ethylidene)benzohydrazide (hereinafter EK6), against isoproterenol-induced myocardial infarction in rats. Changes in biochemistry, cardiac biomarkers, electrocardiography, and histopathology after treatment with EK6 or acenocoumarol (Sintrom) were studied. Animals were randomly divided into 4 groups: vehicle control (C), isoproterenol + Sintrom (ISO + Sin), isoproterenol + EK6 (ISO + EK6), and isoproterenol (ISO). Myocardial infarction was induced by subcutaneous ISO administration at a dose of 85 mg·kg–1·day–1 with a drug-free interval of 24 h on days 6 and 7. Treatment with ISO led to significant elevation (p < 0.05) in serum levels of cardiac injury biomarkers, namely cardiac troponin-T, lactate dehydrogenase, creatine kinase-MB, alanine aminotransferase, and aspartate aminotransferase compared with levels in the vehicle control. A change in the lipid profile was also observed as a significant increase in total cholesterol and triglycerides. Furthermore, ISO caused significant alterations in the electrocardiogram pattern, including significant ST-segment elevation, significant decreased R wave amplitude, and significant increase in heart rate (16%) as well as marked changes in the histopathology of the heart tissue. Pretreatment and co-treatment with newly synthesized coumarin hydrazone restored all ISO-induced biochemical, lipid, cardiac, and histopathological changes in rats with myocardial infarction.

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