1: 84 percent / tetrahydrofuran / 4 h / Ambient temperature 2: 89 percent / 6N NaOH / ethanol / Ambient temperature 3: 1.) 1N KCl, 1N NaOH, subtilisin, 2.) 6N HCl / 1.) water, 1 h, 2.) water, reflux, 4 h 4: NaHCO3, 3N NaOH / tetrahydrofuran / pH 10 View Scheme

triethylamine in ethanol pH=>= 4; 120 h;

1: dimethylformamide 2: aq. HCl View Scheme

1: dimethylformamide 2: (i) aq. HCl, (ii) NH2OH*HCl, NaOAc, (iii) H2, Adams catalyst, aq. HCl View Scheme