title: Ethyl 3-methyl-4-oxo-4,5-dihydro-1H-pyrrolo[2,3-d]pyridazine-2-carboxyl-ate.
abstract: The title compound, C(10)H(11)N(3)O(3), was synthesized by the reaction of 3,5-bis-(ethoxy-carbon-yl)-2-formyl-4-methyl-1H-pyrrole and hydrazine hydrate. The angle between the pyrrole ring and the pyridazinone ring is 0.93 (9)°. In the crystal, inter-molecular N-H⋯O and N-H⋯N hydrogen-bond inter-actions link the mol-ecules into a two-dimensional network.
authors.forename: Shi-Quan
authors.initials: SQ
authors.lastname: Chen
authors.forename: Kai
authors.initials: K
authors.lastname: Jiang
authors.forename: Shi-Fan
authors.initials: SF
authors.lastname: Wang