(a) i. NaOH solution (10%), THF,
25 °C; ii. 2,2-dimethoxy-propane, PTSA, DCM, 25 °C, no purification;
iii. 37, DCC, DMAP, DCM, 52% over 3 steps; (b) i. AcOH/H2O (80:20), 50 °C; ii. Cs2CO3, DMF,
then i-PrI, 25 °C, 66% over 2 steps; (c) 18, NIS, TMSOTf, DCM, −25 °C, 69%; (d) i. NaOH
solution (10%), THF, 25 °C; ii. 2,2-dimethoxy-propane, PTSA,
DCM, 25 °C, no purification; iii. 41, DCC, DMAP,
DCM, 25 °C, 53% over 3 steps; (e) i. AcOH/H2O (80:20),
50 °C; ii. Cs2CO3, DMF, then i-PrI, 25 °C, 58% over 2 steps; (f) 18, NIS, TMSOTf,
DCM, −25 °C, 64%; (g) CuI, DIEA, THF, 25 °C, 60%;
(h) Pd(OH)2, THF, 25 °C, 19%.