phosphine-free ligand than the previously reported ligand, N,N-dimethylglycine, in the Pd-catalyzed Heckreaction for a variety of aryl bromides, aryl iodides, and activated aryl chlorides with a practical turnover number of 10(3). Both kinetic and theoretical studies suggested that N,N-dimethyl-beta-alanine led to faster oxidative addition of an aryl halide to Pd than N,N-dimethylglycine. [reaction: see text]
Cinnamic, p-coumaric and ferulic acids were isolated from pineapple stems (Ananas comosus var. Cayenne). Twenty-four kinds of esters were prepared from these acids, alcohols and the components of Alpinia. Isopropyl 4-hydroxycinnamate (11) and butyl 4-hydroxycinnamate (12) were found to have almost the same effectiveness in antifungalactivity against Pythium sp. at 10 ppm as that of the commercial
Palladium(II)/Cationic 2,2’-Bipyridyl System as a Highly Efficient and Reusable Catalyst for the Mizoroki-Heck Reaction in Water
作者:Shao-Hsien Huang、Jun-Rong Chen、Fu-Yu Tsai
DOI:10.3390/molecules15010315
日期:——
A water-soluble and air-stable Pd(NH3)2Cl2/cationic 2,2’-bipyridyl system was found to be a highly-efficient and reusablecatalyst for the coupling of aryl iodides and alkenes in neatwater using Bu3N as a base. The reaction was conducted at 140 °C in a sealed tube in air with a catalyst loading as low as 0.0001 mol % for the coupling of activated aryl iodides with butyl and ethyl acrylates, providing
Immobilized Pd complexes over HMMS as catalysts for Heck cross-coupling and selective hydrogenation reactions
作者:Peng Wang、Hengzhi Liu、Mengmeng Liu、Rong Li、Jiantai Ma
DOI:10.1039/c3nj01108a
日期:——
High-performance Pd(0) on the surface of hollow magnetic mesoporous spheres (HMMS), with Fe3O4 nanoparticles embedded in the mesoporous shell was prepared. The catalyst was characterized by TEM, XRD, VSM and ICP. It showed high activity for selective hydrogenation of alkynes to alkenes and the Heck coupling reaction. The catalyst could be recovered in a facile manner from the reaction mixture and recycled six times without loss in activity.
Alkyl and Aryl Derivatives Based on p-Coumaric Acid Modification and Inhibitory Action against Leishmania braziliensis and Plasmodium falciparum
作者:Susiany P. Lopes、Lina M. Yepes、Yunierkis Pérez-Castillo、Sara M. Robledo、Damião P. de Sousa
DOI:10.3390/molecules25143178
日期:——
worldwide and are creating a public health problem. The present work evaluates the leishmanicidal and antiplasmodial action of a series of twelve p-coumaric acid derivatives. Of the tested derivatives, eight presented antiparasitic activities 1–3, 8–12. The hexyl p-coumarate derivative (9) (4.14 ± 0.55 μg/mL; selectivity index (SI) = 2.72) showed the highest leishmanicidal potency against the Leishmania