Practical syntheses of optically active carbagalactose and their potential application to the carbocyclic analogues of KRN7000

Carba-alpha- and beta-D-galactose derivatives were efficiently prepared from a cyclohex-3-ene-1,2-diol derivative 1. Regioselective inversion of 2-OH, and stereoselective dihydroxylation of I were accomplished to provide a carba-p-D-galactose derivative 6 in a good yield and with a high stereoselectivity. Stereo-inversion of 1-OH of 6 via oxidation/reduction gave carba-beta-D-galactose derivative 12 with a high stereoselectivity. An efficient coupling of carba-alpha-galactose 12 with an aziridine derivative of sphingosine has been demonstrated to give 1-O-carba-alpha-galactosyl sphingosine derivative 14. (c) 2006 Elsevier Ltd. All rights reserved.