A new, convenient and stereoselective route to the synthesis of (25R)-cholest-5-ene-3β, 26- diol (1) and its radiolabeled analog 4 is described. The key step is a Julia condensation of sulfone 6 with aldehyde 12 to furnish compound 13. Further reduction of the α- hydroxysulfone moiety afforded 22, 23-unsaturated i-steroid 14. The double was reduced by hydrogen and by tritium to provide substrates for the preparation of 1 and 4, respectively.
