Reagents and conditions a) 8, DCI, CH2Cl2 then t-BuOOH, 74% b) HCl-MeOH, 100% of 19, 75% of 22 c) 5, tetrazole, CH2Cl2, 85% d) 13, tetrazole, CH2Cl2 then t-BuOOH, 42% e) Pd/C, H2, then NH4OH, 50 °C, 24 h, 52% of 23, 29% of 3 f) 17, tetrazole, CH2Cl2 then t-BuOOH then Pd/C, H2, then NH4OH, 50 °C, 24 h, 29% of 2, 7% of 25 g) 9, tetrazole, CH2Cl2 then t-BuOOH then HCl-MeOH, 26%.