Scheme 1. Synthesis of Intermediate TEAHP (6) with a Native Glycerol Backbone Conformation.

Reagents and conditions: (a) (i) H₂SO₄, H₂O, and NaNO₂ at 0 °C to rt for 48 h; (ii) MeOH and SOCl₂ at 0 °C to rt, 78%; (b) TrCl, NEt₃, TBAI, and CH₂Cl₂ at rt for 2 h, 86%; (c) LiAlH₄ and Et₂O at 0 °C, 94%; (d) oleic acid, DCC, DMAP, and CH₂Cl₂ at 0 °C to rt, 96%; (e) TFA and CH₂Cl₂ at 0 °C for 0.5 h, 98%; (f) diphenyl phosphite and pyridine for 0.5 h then NEt₃/H₂O (1:1) for 1 h at rt, 90%.