(Z)-Ethyl 2-cyano-3-(1H-imidazol-2-yl)acrylate

The crystal structure of the title compound, C₉H₉N₃O₂, features N—H...N and C—H...O inter­actions. The N—H...N inter­action generates a chain running along the a axis and the C—H...O inter­action generates a chain along the c axis. An intra­molecular C—H...O inter­action is also observed.

2,15-Dioxa-7,18,19,20,23-penta­aza­hepta­cyclo­[21.6.1.1^17,20.0^1,8.0^3,7.0^9,14.0^24,29]hentriaconta-9,11,13,17(31),18,24,26,28-octaen-30-one

In the title compound, C₂₄H₂₃N₅O₃, the oxindole ring system is nearly planar, with a dihedral angle between the two fused rings of 3.3 (1)°. In the fused pyrrolo–oxazole ring system, the oxazole and pyrrolidine rings adopt envelope conformations with the spiro C atom and one of the methyl­ene C atoms, respectively, as the flap atoms. In the crystal, mol­ecules are linked into a helical chain along the b axis via C—H...O inter­actions generating R₂¹(7) and R₂²(8) ring motifs.