Scheme 1. Synthesis of compound 1^{a a}Reagents and conditions: (a) 5-(4'-bromomethyl-biphenyl-2-yl)-1-trityl-1H-tetrazole (5) (1.0 equiv.), K₂CO₃ (1.2 equiv.), DMF, rt, 18h, 75%; (b) Method A: 37% HCl, THF/H2O (4:1), rt, 24h, 82%; or Method B: MeOH, re flux, 16h, 95%; (c) KHCO₃ (1.0 equiv.), MeOH, reflux, 18h, 74%.