Synthesis of Octapeptide 3Boc-Ser(Al)-OH 1 : NaH (2.44 g of a 60% oil dispersion, 1.46 g, 0.061 mol) was suspended in 20 mL of DMF and cooled to 0 °C in a flask fitted with a dropping funnel. Boc-Ser-OH (5.0 g, 0.024 mol) was dissolved in 40 mL of DMF and the resulting solution was transferred to the dropping funnel. This solution was added drop-wise to the NaH solution over a period of 30 minutes. Allyl bromide (2.0 mL, 0.024 mol) was added and the flask contents warmed to room temperature and stirring was continued for 3 hours. The reaction was quenched by the slow addition of 12 mL of water. The solvents were then removed on the rotary evaporator and the residue dissolved in water (40 mL), which was washed with two 20 mL portions of ethyl acetate. The aqueous phase was acidified to pH 2 with the addition of 6 M HCl and extracted with two 40 mL portions of ethyl acetate. The organic phases were combined and dried over anhydrous magnesium sulfate. After filtration, the solvent was evaporated to yield a viscous oil (4.8 g, 82%) which was found to be of sufficient purity to be used in subsequent reactions.1 H NMR (400 MHz, CDCl 3 ): δ 9.1 (1H br s), 5.85 (1H, m), 5.41 (1H, d, J = 8.4 Hz), 5.25 (1H, dq, J = 17.2, 1.5 Hz), 5.19 (1H, dq, J = 10.4, 1.5 Hz), 4.45 (1H, d, J = 8.5 Hz), 4.00 (2H, dt, J = 5.7, 1.5 Hz), 3.90 (1H, dd, J = 9.5, 3.0 Hz), 3.67 (1H, dd, J = 9.5, 3.6 Hz), 1.45 (9H, s).13 C NMR (100 MHz, CDCl 3 ): δ 175. 96, 156.15, 134.25, 118.21, 80.77, 72.80, 69.96, 54.16, 28.70