反应条件
1: 4-(2-chlorophenyl)-3-ethoxycarbonyl-5-methoxycarbonyl-6-methyl-2-[2-phthalimidoethoxymethyl]-1,4-dihydropyridine With methylamine in water T=20 - 45°C; 4.5 h; 2: benzenesulfonic Acid in water T=20°C; pH=1 - 2; 4.5 h; Product distribution / selectivity;