1: (2S,3S,4S)-4-(benzyloxy)-2-methyl-3,4-dihydro-2H-pyran-3-ol With sodium hydride in N,N-dimethyl-formamide T=25°C; 0.0833333 h; 2: benzyl bromide in N,N-dimethyl-formamide T=25°C; 0.5 h;