Scheme 2. Synthesis of compound 2^{a a}Reagents and conditions: (a) 5-(4'-bromomethyl-biphenyl-2-yl)-1-trityl-1H-tetrazole (5) (2.0 equiv.), K₂CO₃ (3.0 equiv.), DMF, rt, 72h, 82%; (b) MeOH, reflux, 72h, 82%; (c) KHCO₃ (1.0 equiv.), MeOH, reflux, 18h, 74%.