二碳酸二叔丁酯

1,1-dimethylethyl 4,7-dihydro-4-(hydroxyimino)-isoxazolo[5,4-c]pyridine-6(5H)-carboxylate

1,1-dimethylethyl 3,5-dioxo-4-[[2-(2-propenyl)hydrazino]methylene]-1-piperidinecarboxylate

1,1-dimethylethyl 2,4,5,7-tetrahydro-4-hydroxy-2-(triphenylmethyl)-6H-pyrazolo[3,4-c]pyridine-6-carboxylate

6-(tert-butoxycarbonyl)-4-hydroxy-2-trityl-4,5,6,7-tetrahydro-2H-pyrazolo[3,4-c]pyridine-7-carboxylic acid