Tdmhedmn: Asynvnctry Vol. 1, No. 2. pp. 119-136.1990 Printed in Great Britain 09574166/?30 $3.00+.00 Pergamm Press plc SYNTHESIS OF HOMOCHIRAL fbHYDROXY-a-AMINOACIDS [(2S,3R,4R)- 3,4-DIHYDROXYPROLINE AND (2S,3R,4R)-3,4-DIHYDROXYPIPECOLIC ACID] AND OF 1,4-DIDEOXY-1,4-IMINO-D-ARABINITOL [DAB11 AND FAGOMINE [1,5-IMINO-1,2,5-TRIDEOXY-D-ARABINO-HEXITOL] George W. J. Fleet* and David R. Witty Dyson Perrins Laboratory, Oxford University, South Parks Road, Oxford OX1 3QY, UK. zyxwvutsrqponmlk (Received 8 December 1989) Abstract Efficient syntheses from diacetone glucose of 1,4-dideoxy-1,4-imino-D- arabinitol, (2S.3R.4R)-3,4-dihydroxyproline, fagomine [ 1,5-imino-1,2,5-uideoxy-D- arobino-hexitol], and (2S,3R,4R)-.3,4dihydroxypipecolic acid by intramolecular nucleophilic displacement by an amino function of 2-0-trifluoromethanesulphonates of anomeric mixtures of methyl furanosides are reported. This paper illustrates the efficient construction of the nitrogen ring of chiral pyrrolidines and piperidines by the intramolecular ring closure of anomeric mixtures of kunino- and 6-amino-2-trifluoromethanesulphonates of methyl furanosides; the syntheses of 1.4~dideoxy-1,4-imino-D-arabinitol - known as DAB1 - (I), (2S,3R,4R)- 3,4-dihydroxyproline (2), fagomine [l,S-imino-1.2,~~trideoxy-D-arubino-hexitol] (3), and (2S,3R,4R)-3,4- dihydroxypipecolic acid (4) from diacetone glucose are reported. All four compounds have been screened as potential inhibitors of HIV replicationt~2 as part of a project looking at the potential of amino sugar derivatives in dissecting glycoprotein biosynthesis; 3 1,4-dideoxy-1,4-imino-L-arabinitol LABl, the enantiomer of (I), is a powerful inhibitor of the cytopathic effect of HIV at concentrations which were not cytotoxic.2*4 (1) (2) (3) (4) LAB1 PR 900483 119