Synonyms: tert-butyl 2-(Methylsulfonyl)-4,6-dihydropyrrolo[3,4-c]pyrazole-5(2H)-carboxylate;2-(Methylsulfonyl)-2,6-dihydropyrrolo[3,4-c]pyrazole-5(4H)-carboxylic acid tert-butyl ester;tert-butyl 2-methanesulfonyl-2H,4H,5H,6H-pyrrolo[3,4-c]pyrazole-5-carboxylate