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

Abstract

Carba-α- and β- 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 1 were accomplished to provide a carba-β- 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-α- d-galactose derivative 12 with a high stereoselectivity. An efficient coupling of carba-α-galactose 12 with an aziridine derivative of sphingosine has been demonstrated to give 1- O-carba-α-galactosyl sphingosine derivative 14.