Synonyms: 5,7-Etheno-1H,5H-cyclopropa(d)(1,2,4)triazolo(1,2-a)pyridazine-6-carboxylic acid, 2,3,5a,6,6a,7-hexahydro-1,3-dioxo-2-phenyl-, methyl ester;5,7-Etheno-1H,5H-cyclopropa[d][1,2,4]triazolo[1,2-a]pyridazine-6-carboxylic acid, 2,3,5a,6,6a,7-hexahydro-1,3-dioxo-2-phenyl-, methyl ester