2,6-dichloropyrazolo[1,2-a]pyrazole-3,5-dione

9,10-dioxa-syn-(hydrogen,bromo)bimane

dimethyl 2,6-dibromo-1,7-dioxo-1H,7H-pyrazolo[1,2-a]pyrazole-3,5-dicarboxylate

dimethyl 2,6-dichloro-1,7-dioxo-1H,7H-pyrazolo[1,2-a]pyrazole-3,5-dicarboxylate

9,10-dioxa-syn-(carboethoxy,bromo)bimane