Synthesis of Enantiomerically Pure Forms of N-Acyl Derivatives of C-Methyl Analogues of the Aminodeoxy Sugar L-Acosamine from Noncarbohydrate Precursors

Article abstract of DOI:10.1021/jo00138a018

The 2S,3R diol 2a and the 3R α-ketol 5b, prepared in fermenting baker's yeast from cinnamaldehyde and α-methylcinnamaldehyde, are converted into the chiral N-trifluoroacetyl deoxy C-methyl-branched amino sugars 15b,c and 19b.Key intermediates in the synthesis are the C4 and C5 chiral aldehydes 9a and 17a and the α,β-unsaturated carbonyl compounds 11a and 18, which upon threo stereoselective addition of ammonia, eventually give 15b,c and 19b.The sterochemistry and the conformations of the aminodeoxy sugar derivatives and of the intermediate lactones are deduced byNMR studies.