1: H2O, NaOH 2: N-hydroxybenzotriazole, triethylamine, dicyclohexylcarbodiimide / formamide 3: H2O, NaOH / methanol 4: N-hydroxybenzotriazole, triethylamine, dicyclohexylcarbodiimide / dimethylformamide 5: NH3 / methanol 6: HCl, acetic acid / various solvent(s) View Scheme