1: With tin(ll) chloride in isopropyl alcohol T=30 - 40°C; 2 h; 2: With sodium hydrogencarbonate in water; isopropyl alcohol

1: 6-O-methylerythromycin A N-oxide With sodium hydrogensulfite in ethanol; water T=20°C; 1 h; 2: With sodium carbonate in ethanol; water 3: formaldehyd With formic acid; sodium carbonate more than 3 stages;