1: 95 percent / 85percent formic acid 2: 72 percent / 1) LiBH4, 2) Pd(PPh3)4 / tetrahydrofuran / 1.5 h / Ambient temperature 3: 97 percent / KOH / methanol; H2O / 1 h / Ambient temperature 4: 1) 3-(5-nitro-2-oxo-1,2-dihydro-1-pyridyl)-1,2-benzisothiazole 1,1-dioxide, TEA, 2) TsOH / 1) 1,2-dichloroethane, 1.5 h, 2) 2 h, reflux View Scheme