Synthesis and antibacterial activities of novel oxazine and thiazine ring-fused tricyclic quinolonecarboxylic acids: 10-(Alicyclic amino)-9-fluoro-7-oxo-7<i>H</i>-pyrido[1,2,3-<i>de</i>][1,4]benzoxazine-6-carboxylic acids and the corresponding 1-thia congeners
Several analogs 4 and 5 of Ofloxacin (1) which contain the oxazine and thiazine rings fused with a quinolone carboxylic acid moiety, respectively, were prepared and their in vitro and in vivo antibacterial activities were compared with those of 1 and its previously prepared 3-exo-methylene analogs 2 and 3. Unlike 1, 2, and 3, analogs 4 and 5 possess an antiaromatic oxazine and thiazine moiety and show
Regioselective 2-alkylation of indoles with α-bromo esters catalyzed by Pd/P,P=O system
作者:Wei Tian、Bowen Li、Duanshuai Tian、Wenjun Tang
DOI:10.1016/j.cclet.2021.06.091
日期:2022.1
A palladium-catalyzed 2-alkylation of indoles with α-bromoesters is developed by employing a P,P=O ligand. The method features excellent regioselectivities, mild reaction conditions, and good functional group compatibility. The employment of the P,P=O ligand as well as 4Å molecular sieves were crucial for the success of the transformation. Mechanistic studies indicate the reaction proceed through