4-Acetyl-6-(2-benzyloxy-3,4-dimethoxy-phenyl)-7-methyl-pyrrolo[3,4-c]pyridine-1,3-dione

2-(2-Benzyloxy-3,4-dimethoxy-phenyl)-3-methyl-7-methylene-5-oxo-5,7-dihydro-furo[3,4-b]pyridine-4-carboxylic acid methyl ester

6-(2-Benzyloxy-3,4-dimethoxy-phenyl)-4-(1-hydroxy-ethyl)-7-methyl-pyrrolo[3,4-c]pyridine-1,3-dione

2-(2-Benzyloxy-3,4-dimethoxy-phenyl)-3,7-dimethyl-5-oxo-5,7-dihydro-furo[3,4-b]pyridine-4-carboxylic acid methyl ester

2-(2-Benzyloxy-3,4-dimethoxy-phenyl)-7-hydroxy-3,7-dimethyl-5-oxo-5,7-dihydro-furo[3,4-b]pyridine-4-carboxylic acid methyl ester