Abstract
-
The synthesis of four of the diastereoisomers of 2-acetyl-5-(l ,2,3,4-tetrahydroxybutyl)thiazole and two of the diastereoisomers of 2-acetyl-5-( 1,2,3,4,5-pentahydroxypentyl)thiazole and 2-acetyl-4-( 1,2,3,4,5-pentahydroxypentyl)thiazole are reported. These syntheses involve the condensation of 5- or 4-metallated 2-( 1,1 -dimethoxyethyl)thiazoles with 2,3-O-isopropylidene-D-erythrono-l,4-lactone or 5-O-(tert-butyldimethylsilyl)-2,3-O-isopropylideneD-ribonolactone followed by reductive ring-opening of the resulting lactols. The stereochemistries and structures of some key compounds have been determined by single crystal X-ray structural analysis.