A mixture of Intermediate 95a (0.50 g, 2.2 mmol) in dry THF (17 mL) was treated with triphenylphosphine (1.13 g, 4.32 mmol) and (S)-(+)-1-Benzyloxy-2-propanol (0.52 mL, 3.24 mmol). The mixture was cooled to 0° C. then diisopropylazodicarboxylate (0.85 mL, 4.32 mmol) was added dropwise. After stirring at ambient temperature for 1.75 h the mixture was treated with water (0.2 mL) then applied to a pre-conditioned (with MeOH) SCX-2 cartridge. The cartridge was eluted with MeOH then 2N NH3 in MeOH. The product containing fractions were combined and concentrated in vacuo to a viscous brown oil. The oil was purified by FCC, using 0-30% EtOAc in cyclohexane, to give the title compound as a golden oil (0.37 g, 45%). LCMS (Method 3): Rt 3.71 min, m/z 380.3 [MH+].
