6-[(S)-Hydroxy[(5R)-5,6,7,8-tetrahydro-4-methoxy-6-methyl-1,3-dioxolo[4,5-g]isoquinolin-5-yl]methyl]-2,3- dimethoxybenzaldehyde; [S-(R*,S*)]-6-[hydroxy(5,6,7,8-tetrahydro-4-methoxy-6-methyl-1,3-dioxolo[4,5-g]isoquinolin -5-yl)methyl]-2,3-dimethoxybenzaldehyde