1139688-75-7Relevant academic research and scientific papers
Practical, highly convergent, asymmetric synthesis of a selective PPARγ modulator
Maligres, Peter E.,Humphrey, Guy R.,Marcoux, Jean-Francois,Hillier, Michael C.,Zhao, Dalian,Krska, Shane,Grabowski, Edward J.J.
experimental part, p. 525 - 534 (2010/04/22)
A practical, highly convergent, asymmetric synthesis of a selective PPARγ modulator 1 is described. The inhibitor contains two key components, a 6-trifluoromethoxy-3-acylindole (6) and (R)-raryloxybutanoic acid derivative (10). Twomethods were developed to overcome the regioselectivity issues encountered in the preparation of the 6-substituted indole. The first involved an intramolecular Heck reaction of an iodoaryl enamine. The second involved application of a catalytic Meerwein arylation reaction between 2-nitro-4-trifluoromethoxyaniline and isopropenyl acetate and subsequent reductive cyclization. The α-aryloxybutanoic acid was prepared via an asymmetric hydrogenation of the corresponding α-aryloxy-α,β- unsaturated acid. Tetrabutylammonium iodidecatalyzed coupling of the two fragments and ester hydrolysis completed the convergent synthesis. The described convergent synthesis was used to prepare >3 kg of drug substance 1 in 50% overall yield and with >99.5% ee.
