Synthesis of N-trifluoroacetyl-L-acosamine and -L-daunosamine

Abstract
N-Trifluoroacetyl-L-acosamine (18) has been chirally synthesised from the chiral educt (1) obtained from cinnamaldehyde and bakers' yeast, whereas N-trifluoroacetyl-L-daunosamine (17) was obtained by inverting the configuration at C-4 of the intermediate δ-lactone (11); compounds (18) and (17) have also been prepared from L-threonine via the δ- and γ-lactones (14) and (9), by inverting the configuration at position 5 of (9).