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261.
Jairo Quiroga Jorge Trilleras Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(1):o47-o49
In the title compound, C11H11N3O·0.5H2O, the water molecule lies across a twofold rotation axis in the space group Pbcn. The bond distances in the organic component provide evidence for polarization of the electronic structure. The molecular components are linked into puckered sheets of R108(34) rings by a combination of O—H...N and N—H...O hydrogen bonds; adjacent sheets are weakly linked by an aromatic π–π stacking interaction. Comparisons are made with some fused‐ring analogues. 相似文献
262.
Henry Insuasty Edison Castro Edison Snchez Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(3):o141-o146
In O‐ethyl N‐benzoylthiocarbamate, C10H11NO2S, the molecules are linked into sheets by a combination of two‐centre N—H...O and C—H...S hydrogen bonds and a three‐centre C—H...(O,S) hydrogen bond. A combination of two‐centre N—H...O and C—H...O hydrogen bonds links the molecules of O‐ethyl N‐(4‐methylbenzoyl)thiocarbamate, C11H13NO2S, into chains of rings, which are linked into sheets by an aromatic π–π stacking interaction. In O,S‐diethyl N‐(4‐methylbenzoyl)imidothiocarbonate, C13H17NO2S, pairs of molecules are linked into centrosymmetric dimers by pairs of symmetry‐related C—H...π(arene) hydrogen bonds, while the molecules of O,S‐diethyl N‐(4‐chlorobenzoyl)imidothiocarbonate, C12H14ClNO2S, are linked by a single C—H...O hydrogen bond into simple chains, pairs of which are linked by an aromatic π–π stacking interaction to form a ladder‐type structure. 相似文献
263.
Novel 6-chloropyrazolo[3,4-b]pyridine-5-carbaldehydes 5 have been synthesized from the 4,5-dihydropyrazolo[3,4-b]pyridine-6-ones 4 via Vilsmeier-Haack reaction. Further treatment of carbaldehydes 5 with acetophenones 6 and hydrazine hydrate afforded chalcone analogues 7 and dipyrazolo[3,4-b:4′,3′-e]pyridines 8, respectively. 相似文献