| abstract |
There is disclosed a novel method for the syntheses of chiral pyrrolidines and piperidines by the intramolecular ring closure of anomeric mixtures of 4-amino- and 5-amino-2-trifluoromethanesulfonates of methyl furanosides. The novel method preferably provides for the efficient syntheses from diacetone glucose of 1,4-dideoxy-1,4-imino-D-arabinitol--known as DAB1, (2S,3R,4R)-3,4-dihydroxyproline, fagomine [1,5-imino-1,2,5-trideoxy-D-arabino-hexitol], and (2S,3R,4R)-3,4-dihydroxypipecolic acid by intramolecular nucleophilic displacement by an amino function of 2-O-trifluoromethanesulphonates of anomeric mixtures of methyl furanosides. |