The four 1-deoxy-d-ketohexoses—1-deoxy-d-psicose, 1-deoxy-d-fructose, 1-deoxy-d- sorbose and 1-deoxy-d-tagatose—were synthesised by methyl lithium addition to suitably protected and readily available pentonolactones. The 1-deoxy-l-ketohexoses are available from the enantiomeric lactones. The NMR studies on aqueous solutions of each diastereomer show that the relative amounts of open chain ketones, α-and β-pyranoses, ...