Asymmetric synthesis of 2-Acetyl-4(5)-(1,2,3,4-tetrahydroxybutyl)imidazoles

摘要

A method for preparing the eight stereosisomers of the biologically active compound (1R,2S,3R)-2- acetyl-4(5)-(1,2,3,4-tetrahydroxybutyl)imidazole (THI, 1) is reported. This method employs a palladium(0)-catalyzed coupling of 1-(ethoxymethyl)-4-iodoimidazole (7) to functionalized vinyl- stannanes (R)- or (S)-12a,b or 13a,b or 1-alkynylstannanes (R)- or (S)-6a,b to introduce the C-4 imidazole four-carbon side chain. The 1,2-dihydroxy functionality of the butyl side chain was introduced by Sharpless catalytic asymmetric diyhydroxylation reactions.