Stereoselective synthesis of artificial C-nucleosides

QD Chemistry

Stambasky, Jan ; Kocovsky, Pavel

University:University of Glasgow

Department:School of Chemistry

关键词: C-nucleosides, iridium, organometallic, synthesis, catalytic;   

Others  :  http://theses.gla.ac.uk/198/1/2008stambaskyphd.pdf

来源: University of Glasgow

【 摘 要 】

Reported herein is a conceptually new synthetic route to 1’-aryl C-ribofuranosides and their 2’,3’-didehydro 2’,3’-dideoxy (D4) analogues. We have successfully implemented a divergent synthetic route capable to reach two important, biologically significant groups of compounds. The first two strategic transformations are common for both families of target compounds (asymmetric allylic substitution, and ring-closing metathesis). D4 C nucleoside analogues are synthesised in a three step procedure, and 1’-aryl ribofuranoses are constructed in a four step procedure.The target compounds were prepared in an excellent enantioand diastereopurity, in good overall yields. The yield in the synthesis of 1’-aryl-2’,3’-didehydro-1’,2’,3’-trideoxyribofunanoses is up to 46% over all the reaction steps. The overall yield of the 1’-arylribofuranoses is up to 42%. All the strategic transformations rely on catalytic oranometallic reactions employing group 8a transition metals. All the reactions have been optimized with a view of maximal atom efficiency and environmental impact. In summary, our new methodology is perfectly suitable for the synthesis of 1’ arylribofuranoses, and their D4 analogues, bearing non-ortho-substituted aromatics and hereroaromatics, lacking coordinating (nitrogen) substituents or heteroatoms. In this point of view the most promising target application is the synthesis of lipophilic isosters of ribonucleosides for the RNA studies.