The BF3·Et2O-catalysed acetolysis of steroid sapogenins diosgenin, sarsasapogenin and tigogenin in dichloromethane as the solvent instead of acetic anhydride afforded (20S)- and (20R)-22,26-epoxycholestanes (compounds 1 and 2). 22S-23-Acetylsapogenins (compounds 4) were