A simple and mild method for the conversion of varieties of alpha,beta-unsaturated carboxylic acids to the corresponding bromoalkenes using diacetoxyiodobenzene (IBD) in combination with tetraethyl-ammonium bromide (TEAB) at room temperature is discussed. Advantages of this system are short reaction time, easy work up and gave good to excellent yields.
Synthesis, conformational preferences, and biological activity of conformational analogues of the microtubule-stabilizing agents, (−)-zampanolide and (−)-dactylolide
作者:Jeffrey L. Henry、Matthew R. Wilson、Michael P. Mulligan、Taylor R. Quinn、Dan L. Sackett、Richard E. Taylor
DOI:10.1039/c9md00164f
日期:——
conformation for bioactivity while reducing the number of synthetic manipulations necessary for their synthesis. Analogues 3, 4 and 5 were prepared via total synthesis, and their conformational preferences were determined through computational and high-field NMR studies. While no observable activities were present in dactylolide analogues 3 and 4, zampanolide analogue 5 exhibited sub-micromolar cytotoxicity
Regioselective Synthesis of Natural and Unnatural (Z)-3-(1-Alkylidene)phthalides and 3-Substituted Isocoumarins Starting from Methyl 2-Hydroxybenzoates
benzene ring, have been selectively and efficiently synthesized by a new protocol which involves: (i) the conversion of methyl 2-hydroxybenzoates into the corresponding nonaflates; (ii) Pd-catalyzed alkynylation reactions of these derivatives; (iii) the conversion of the so obtained methyl 2-(1-alkynyl)benzoates into the corresponding carboxylic acids followed by a transition metal-catalyzed heteroannulation
Ultrasound assisted synthesis and cytotoxicity evaluation of known 2′,4′-dihydroxychalcone derivatives against cancer cell lines
作者:Joan Villena、Iván Montenegro、Bastian Said、Enrique Werner、Susana Flores、Alejandro Madrid
DOI:10.1016/j.fct.2021.111969
日期:2021.2
This work reports on the development of an efficient and ecofriendly ultrasoundassisted method for the high yield synthesis (70.0-94.0%) of eighteen oxyalkylated derivatives of 2',4'-dihydroxychalcone. Synthesized compounds were subjected to in vitro biological assays against HT-29 (colorectal), MCF-7 (breast), and PC-3 (prostate) human tumor cell lines, these cell lines are among the ten most aggressive
Palladium-catalysed carbonylation reactions have been developed in the presence of formic acid as carbon monoxide source. α,β-Unsaturated carboxylic acids and esters were synthesized by the transformation of alkenylhalides in moderate to good yields. The selection of the base proved to be crucial regarding the reaction outcome. A set of various substrates were proven under optimised reaction conditions