Scheme 8

Synthesis of xylose nucleolipids. a) 12, dry DCM,1H-tetrazole, H₂O₂, rt, 4 h.; b) 13, dry DCM, 1H-tetrazole, H₂O₂, rt, 4 h.; c) H_2, Pd/C, THF, rt, 48 h. Compounds 47 and 48 were isolated as 2Na⁺ salt.