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981.
Strobilurins have become one of the most important classes of agricultural fungicides. To search for new strobilurin derivatives with high activity against resistant pathogens, a series of new β‐methoxyacrylate analogues containing substituted pyrimidine in the side chain with strobilurin pharmacophore were synthesized and their biological activities were tested. The compounds were confirmed and characterized by 1H‐NMR, elemental analysis and mass spectroscopy. The bioassays indicated that most of the compounds 1 exhibited potent antifungal activities against Colletotrichum orbiculare, Botrytis cinerea Pers and Phytophthora capsici Leonian at a concentration of 50 μg mL?1. Notably, compound 1b (R = 2,5‐dimethylphenyl) showed better antifungal activity against all the tested fungi than the commercial strobilurin fungicide azoxystrobin. 相似文献
982.
Pyrrole was polymerized on the surface of titanium foam using FeCl3 as oxidant and the as-synthesized product could be directly used as electrode for supercapacitor. The globular polypyrrole (PPy) particles were firmly loaded on the substrate with high density. The morphology study of PPy film is observed in SEM images, the XRD, FTIR and UV–vis spectra reveal the structure and crystalline of PPy nanoparticles. The electrochemical properties of PPy modified electrode are investigated by cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) and cycle life techniques. The electrochemical measurements showed such a PPy–Ti electrode had a wide working potential window, a high specific capacitance of 855 F g−1 and excellent cycle stability at a discharge current density of 1 A g−1. 相似文献
983.
Jian‐You Li Ying Peng Ling‐Zhi Li Pin‐Yi Gao Chang Gao Su‐Xia Xia Shao‐Jiang Song 《Helvetica chimica acta》2013,96(2):313-319
Two new abietane‐type diterpenoids, named triptobenzene R ( 1 ) and triptobenzene S ( 2 ), together with three known abietane‐type diterpenoids, triptophenolide ( 3 ), triptonodiol ( 4 ), and triptonoterpene methyl ether ( 5 ), were isolated from the roots of Tripterygium wilfordii Hook . f. Their structures and relative configurations were established by detailed spectral studies, including 1D‐ and 2D‐NMR (HSQC, HMBC, and NOESY), and HR‐ESI‐TOF‐MS, and by comparison with published data. Their absolute configurations were assigned by the CD technique, applied for the first time to abietane diterpenes from Tripterygium wilfordii. Compound 2 is the first abietane‐type norditerpenoid isolated from the genus Tripterygium. 相似文献
984.
An environmentally friendly process is reported for the palladium(II)‐catalyzed cyclofunctionalization of allylic hydroxylamine derivatives using a catalytic amount of copper(II) acetate and molecular oxygen as the cooxidant. 相似文献
985.
2‐Alkylthio‐3‐alkyl‐5‐phenylmethylidene‐4H‐imidazol‐4‐ones 6 were synthesized by N‐alkylation and S‐alkylation of 2‐thioxo‐5‐phenylmethylidene‐4‐imidazolidinone 5, which was obtained via cyclization of vinyl isothiocyanate 4 with excess ammonium hydroxide (28% NH3 in water). 相似文献
986.
One-pot etherification reaction of aromatic and some aliphatic carbonyl compounds with organic halides in the presence of sodium hydride as a reducing reagent proceeded smoothly in dioxane, a polar solvent with higher boiling point, to provide desired ethers in moderate to high yields. 相似文献
987.
The Knoevenagel condensation of Meldrum's acid with aromatic aldehydes proceeded efficiently in a reusable ionic liquid, ethylammonium nitrate, at room temperature in the absence of any catalyst with high yields. 相似文献
988.
A practical protocol was disclosed for the nickel-catalyzed C-alkylation of 9-fluorenone hydrazone with alcohols using t-BuOK as the base, and 9-monoalkylated fluorene derivatives were obtained in good yields under the benign conditions. 相似文献
989.
Two types of β‐enaminoketone derivatives of 3‐(2‐oxo‐2‐arylethylidene)‐3,4‐dihydro‐1H‐quinoxalin‐2‐ones and 3‐(2‐oxo‐2‐arylethylidene)‐3,4‐dihydro‐benzo[1,4]oxazin‐2‐ ones were effectively and conveniently prepared in good to excellent yields under solvent‐free conditions via the catalysis of sulfamic acid in the corresponding condensations of o‐phenylenediamine and o‐aminophenol with ethyl 2,4‐dioxo‐4‐arylbutyrate respectively. The compounds were confirmed by IR, 1H NMR, and 13C NMR, and a representative was further determined by X‐ray crystallography. 相似文献
990.
Molecular oxygen (1 atm) conveniently reacts with olefins in the presence of simple supported metal heterogeneous catalysts and aldehydes (e.g., isobutyraldehyde and benzaldehyde) at room temperature to give epoxides in good yields. 相似文献