19367-38-5Relevant articles and documents
Higuchi,Donnelly
, p. 787,789 (1978)
Nitrification inhibitors from the root tissues of Brachiaria humidicola, a tropical grass
Gopalakrishnan, Subramaniam,Subbarao, Guntur V.,Nakahara, Kazuhiko,Yoshihashi, Tadashi,Ito, Osamu,Maeda, Ikuko,Ono, Hiroshi,Yoshida, Mitsuru
, p. 1385 - 1388 (2007)
Nitrification inhibitory activity was found in root tissue extracts of Brachiaria humidicola, a tropical pasture grass. Two active inhibitory compounds were isolated by activity-guided fractionation, using recombinant Nitrosomonas europaea containing luxAB genes derived from the bioluminescent marine gram-negative bacterium Vibrio harveyi. The compounds were identified as methyl-p-coumarate and methyl ferulate, respectively. Their nitrification inhibitory properties were confirmed in chemically synthesized preparations of each. The IC50 values of chemically synthesized preparations were 19.5 and 4.4 μM, respectively. The ethyl, propyl, and butyl esters of p-coumaric and ferulic acids inhibited nitrification, whereas the free acid forms did not show inhibitory activity.
Renewable benzoxazine monomers from Lignin-like naturally occurring phenolic derivatives
Comí, Marc,Lligadas, Gerard,Ronda, Juan C.,Galià, Marina,Cádiz, Virginia
, p. 4894 - 4903 (2013)
The benzoxazines of three naturally occurring phenylpropanoid phenols: ferulic, coumaric, and phloretic acids, and their esters are described. Benzoxazines with conjugated unsaturated chains exhibit unusual poor thermal stability and degrade partially at the polymerization temperature making necessary the use of a catalyst (BF3.Et2O) to low the polymerization temperature and prevent degradation. Polybenzoxazines are prepared thermally and characterized by DSC and TGA techniques. The resulting materials have superior Tgs when compared with those prepared from an unsubstituted monofuctional benzoxazine due to the additional crosslinking through the ester and carboxylic moieties.
Induction of phenolic compounds in two cultivars of cucumber by treatment of healthy and powdery mildew-infected plants with extracts of Reynoutria sachalinensis
Daayf, Fouad,Ongena, Marc,Boulanger, Renald,El Hadrami, Ismail,Belanger, Richard R.
, p. 1579 - 1593 (2000)
Accumulation of phenolic compounds (p-coumaric, caffeic, and ferulic acids and p-coumaric acid methyl ester) was followed in susceptible (Mustang) and tolerant (Flamingo) cucumber (Cucumis sativus) cultivars. The objective was to determine whether these compounds played a role in resistance against powdery mildew following a prophylactic treatment with Milsana (leaf extracts from the giant knot weed Reynoutria sachalinensis, polygonaceae). This treatment significantly reduced the incidence of powdery mildew in both cultivars. Phenolic compounds were extracted from leaves. In the hydrolyzed fraction containing phenolic aglycones, levels of p-coumaric, caffeic, and ferulic acids and of p-coumaric acid methyl ester increased in all treatments (with leaf extracts of R. Sachalinensis, powdery mildew, or both) except the control, one or two days after treatment. In the fraction containing free phenolics, from the tested compounds, only ferulic acid showed an increase in cv. Flamingo (tolerant), and was particularly evident following treatments. On the other hand, the amounts of hydroxycinnamic acids increased rapidly in the two cultivars following Milsana treatment, suggesting their role in disease reduction. All compounds showed antifungal activity when tested against common pathogens of cucumber (Botrytis cinerea, Pythium ultimum, and P. aphanidermatum), but in general methyl esters were more fungitoxic than their corresponding free acids. This study suggests that cucumber is able to release antifungal compounds that are instrumental in repressing powdery mildew infection. This response is seemingly independent from the level of genetic resistance associated with each cultivar.
Pd salen complex@CPGO as a convenient, effective heterogeneous catalyst for Suzuki–Miyaura and Heck–Mizoroki cross-coupling reactions
Ghabdian, Mahdieh,Nasseri, Mohammad Ali,Allahresani, Ali,Motavallizadehkakhky, Alireza
, p. 1713 - 1728 (2018/05/25)
A Pd(II) Schiff base complex supported on graphene oxide nanosheets (Pd(II) salen@CPGO) has been synthesized and characterized by FT-IR, ICP-AES, XRD, SEM/EDX and TEM. The synthesized nanocatalyst has been found to be an efficient heterogeneous catalyst for Suzuki–Miyaura and Heck–Mizoroki coupling reactions. Pd(II) salen@CPGO could be separated and recovered easily from the reaction mixture and recycled several times without a discernible decrease in its catalytic activity. The construction of a solid sheet-supported Pd catalyst would be expected to be a promising system to perform heterogeneous catalytic reactions.
Optimization of the reaction conditions for the synthesis of dihydrobenzofuran neolignans
Crotti, Ant?nio E. M.,Dias, Herbert J.,Rodrigues, Matheus L.
, p. 20 - 28 (2020/12/28)
We have optimized the experimental conditions for the silver(I)-promoted oxidative coupling of methyl p-coumarate (I) and methyl ferulate (II), which is the most frequently used methodology to synthesize the bioactive dihydrobenzofuran neolignans 1 ((±)-trans-dehydrodicoumarate dimethyl ester) and 2 ((±)-trans-dehydrodiferulate dimethyl ester). Most of the tested conditions affected the conversion (i.e., the consumption of I and II) and the selectivity (i.e., the percentage of I and II that was converted into 1 and 2, respectively), so the optimized conditions were the ones that afforded the best balance between conversion and selectivity. Silver(I) oxide (0.5 equiv.) is the most efficient oxidant agent amongst the silver(I) reagents that were tested to convert methyl esters I and II into compounds 1 and 2, respectively. Acetonitrile, which has not yet been reported as a solvent for this reaction, provided the best balance between conversion and selectivity, besides being "greener" than other solvents that are more often employed (e.g., dichloromethane and benzene). Under the optimized conditions, the reaction time decreased from 20 to 4 h without significantly impacting the conversion and selectivity.
Preparation method of esmolol hydrochloride intermediate
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Paragraph 0041-0043; 0046-0048, (2020/09/16)
The invention belongs to the field of organic synthesis of medicines, and particularly relates to a preparation method of a medicine esmolol hydrochloride intermediate for treating hypertension. The synthesis route provided by the invention comprises the following steps: reacting p-bromophenol with methyl acrylate in the presence of a palladium catalyst and a phosphine ligand to generate 3-(4-hydroxyphenyl) methyl acrylate; and hydrogenating the generated 3-(4-hydroxyphenyl) methyl acrylate in the presence of a palladium-carbon catalyst to obtain a target product methyl 4-hydroxyphenylpropionate. The method has the advantages of short reaction steps, cheap and accessible raw materials, simple technique and convenience of operation, and does not need special reaction conditions, thereby being more suitable for industrial production.
