dimethyl spiro[4aH-pyrrolo[1,2-b]pyridazine-5,9'-fluorene]-6,7-dicarboxylate

methyl 2-pyridazin-1-ium-1-ylacetate,bromide

ethyl 2-pyridazin-1-ium-1-ylacetate,bromide

3-iodopyridazine

spiro[9a,9b-dihydro-3aH-furo[1,2]pyrrolo[3,5-b]pyridazine-4,3'-oxolane]-1,2',3,5'-tetrone