2,2-Dimethyl-5-(4H-1,2,4-triazol-4-ylamino­methyl­ene)-1,3-dioxane-4,6-dione monohydrate

In the title compound, C₉H₁₀N₄O₄·H₂O, the triazole ring is nearly planar. The 1,3-dioxane-4,6-dione ring exhibits a half-chair conformation. Two intra­molecular N—H...·O hydrogen bonds, with O...H distances of 2.23 (2) and 1.99 (2) Å, and two inter­molecular O—H...·N hydrogen bonds, with N...H distances of 1.92 (3) and 1.94 (4) Å, are observed.

2,2-Dimethyl-5-[(1,2,4-triazin-3-ylamino)methyl­ene]-1,3-dioxane-4,6-dione

In the title compound, C₁₀H₁₀N₄O₄, the triazine ring is nearly planar. The 1,3-dioxane-4,6-dione ring exhibits a half-chair conformation. The mol­ecule is disordered and the structure has been refined using a split model.

6-Nitro­quinolin-2(1H)-one

The title compound, C₉H₆N₂O₃, is nearly planar, with maximum deviations from the mean plane of −0.024 (3) Å for the C atom para to the ring N atom and 0.048 (2) Å for one of the nitro O atoms. Three C—H...O and one N—H...O intermolecular hydrogen bonds stabilize the crystal structure.

5-[(2-Bromo­phenyl­amino)methyl­ene]-2,2-dimethyl-1,3-dioxane-4,6-dione

In the title compound, C₁₃H₁₂BrNO₄, the 1,3-dioxane-4,6-dione ring exhibits a half-chair conformation. The mol­ecules are linked by C—H...O hydrogen bonds. The amino H atom has one intra­molecular contact to a carbonyl O atom, forming a six-membered ring.