1: With thionyl chloride; 1,8-diazabicyclo[5.4.0]undec-7-ene in isopropanol acetate T=20 - 30°C; 18.5 h; 2: With hydroxylamine in tetrahydrofuran; isopropanol acetate; water T=0 - 10°C; 3: With hydrogenchloride in tetrahydrofuran; isopropanol acetate; water T=0 - 30°C; 1 h;