78540-03-1Relevant articles and documents
Successive Pd-Catalyzed Decarboxylative Cross-Couplings for the Modular Synthesis of Non-Symmetric Di-Aryl-Substituted Thiophenes
Douglas, Liam Z.,Forgione, Pat,Liu, Jiang Tian,Messina, Cynthia
, (2020/08/17)
Oligothiophenes are important organic molecules in a number of burgeoning industries as semi-conducting materials due to their extensive π-conjugation and charge transport properties. Typically, non-symmetric, di-aryl-substituted thiophenes are prepared by the successive formation of Grignards, organotin, and/or boronic acid intermediates that can be subsequently employed in cross-coupling reactions. While reliable, these approaches present synthetic difficulties due to the reactivity of organo-metallic/pseudo-metallic species, and produce considerable amounts of waste due to necessary pre-functionalization. We have developed a decarboxylative cross-coupling route as an effective strategy for the modular and less wasteful synthesis of a wide range of non-symmetric, di-arylthiophenes. This method uses a thiophene ester building block for successive decarboxylative palladium-catalyzed couplings that allows for the efficient synthesis and evaluation of the opto-electronic properties of a library of candidate semi-conductors with functional groups that could be challenging to access using previous routes.
Macrocyclic prolinyl acyl guanidines as inhibitors of β-secretase (BACE)
Boy, Kenneth M.,Guernon, Jason M.,Wu, Yong-Jin,Zhang, Yunhui,Shi, Joe,Zhai, Weixu,Zhu, Shirong,Gerritz, Samuel W.,Toyn, Jeremy H.,Meredith, Jere E.,Barten, Donna M.,Burton, Catherine R.,Albright, Charles F.,Good, Andrew C.,Grace, James E.,Lentz, Kimberley A.,Olson, Richard E.,Macor, John E.,Thompson, Lorin A.
, p. 5040 - 5047 (2015/11/09)
The synthesis, evaluation, and structure-activity relationships of a class of acyl guanidines which inhibit the BACE-1 enzyme are presented. The prolinyl acyl guanidine chemotype (7c), unlike compounds of the parent isothiazole chemotype (1), yielded compounds with good agreement between their enzymatic and cellular potency as well as a reduced susceptibility to P-gp efflux. Further improvements in potency and P-gp ratio were realized via a macrocyclization strategy. The in vivo profile in wild-type mice and P-gp effects for the macrocyclic analog 21c is presented.
Carboxylation of indoles and pyrroles with CO2 in the presence of dialkylaluminum halides
Nemoto, Koji,Onozawa, Satoru,Egusa, Naoki,Morohashi, Naoya,Hattori, Tetsutaro
experimental part, p. 4512 - 4514 (2009/11/30)
The Lewis acid-mediated carboxylation of arenes with CO2 has been successfully applied to 1-substituted indoles and pyrroles by using dialkylaluminum chlorides instead of aluminum trihalides. Thus, the carboxylation of 1-methylindoles, 1-benzyl-, and 1-phenylpyrroles proceeds regioselectively with the aid of an equimolar amount of Me2AlCl under CO2 pressure (3.0 MPa) at room temperature to afford the corresponding indole-3-carboxylic acids and pyrrole-2-carboxylic acids in 61-85% yields, while the same treatment of 1,2,5-trimethylpyrrole affords the 3-carboxylic acid in 52% yield.
