s hydrogen or an acyl group, for example an acetyl group; and (b) introducing a trityl group, for example a dimethoxytrityl, monomethoxytrityl, or trityl group to the primary hydroxyl of the product of (a) and (c) introducing a phosphorus containing group having Formula 78: [0295] wherein R1 can include the groups: [0296] and wherein each R2 and R3 independently can include the groups: [0297] to t