organic compounds
The molecules of ethyl 4-(5-amino-3-methyl-1H-pyrazol-1-yl)benzoate, C13H15N3O2, are linked by two independent N—HO hydrogen bonds into a chain of edge-fused and alternating R42(8) and R22(20) rings. A combination of N—HN and N—HO hydrogen bonds links the molecules of methyl 4-(5-amino-3-tert-butyl-1H-pyrazol-1-yl)benzoate, C15H19N3O2, into sheets of alternating R22(20) and R66(32) rings. In 4-(5-amino-3-methyl-1H-pyrazol-1-yl)benzoic acid monohydrate, C11H11N3O2·H2O, the molecular components are linked into a three-dimensional framework structure by a combination of five independent hydrogen bonds, two of O—HN type and one each of O—HO, N—HO and N—HN types.
organic compounds
The bond distances in the title compound, C11H16N4, provide evidence for peripheral delocalization of electrons. The molecules are linked by two independent N-HN hydrogen bonds into a three-dimensional framework structure.
organic compounds
The molecules of 3-tert-butyl-5-[(4-methoxybenzyl)amino]-1-phenyl-1H-pyrazole, C21H25N3O, are linked into simple C(9) chains by a single C—HN hydrogen bond. 5-[(Benzotriazol-1-ylmethyl)(4-methoxybenzyl)amino]-3-tert-butyl-1-phenyl-1H-pyrazole, C28H30N6O, crystallizes with Z′ = 2 in the space group P21/c. The molecules are weakly linked into centrosymmetric tetramolecular aggregates by a combination of C—HN and C—HO hydrogen bonds.
organic compounds
Molecules of methyl 4-[(5-methyl-1H-pyrazol-3-yl)amino]-3-nitrobenzoate, C12H12N4O4, (I), exhibit a polarized (charge-separated) structure in the nitroaniline portion. The molecules are linked into chains of edge-fused R22(16) and R22(22) rings by a combination of N-HO(carbonyl) and C-HO(nitro) hydrogen bonds. Methyl 1-(5-methyl-1H-pyrazol-3-yl)-1H-benzimidazole-5-carboxylate, C13H12N4O2, (II), which is readily formed from (I) by reduction followed by ring formation, crystallizes with Z' = 2 in the space group P. Each of the two independent molecular types is linked into sheets of R44(28) rings by a combination of N-HN and C-HO(carbonyl) hydrogen bonds.
organic compounds
The title compound, C15H12N2O3, crystallizes with Z' = 2 in the space group P and the intramolecular dimensions show evidence for a polarized molecular-electronic structure. Each of the two independent types of molecule forms its own hydrogen-bonded supramolecular substructure, and these are entirely different from one another: one type of molecule forms a chain of edge-fused rings, while the other type forms sheets.
organic compounds
Both 6-(1H-indol-3-yl)-3-methyl-4-(4-methylphenyl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-5-carbonitrile and 6-(1H-indol-3-yl)-3-methyl-4-(4-methoxyphenyl)-1-phenyl-1H-pyrazolo[3,4-b]pyridine-5-carbonitrile crystallize from dimethylformamide solutions as stoichiometric 1:1 solvates, viz. C29H21N5·C3H7NO, (I), and C29H21N5O·C3H7NO, (II), respectively; however, 6-(1H-indol-3-yl)-3-methyl-1-phenyl-4-(3,4,5-trimethoxyphenyl)-1H-pyrazolo[3,4-b]pyridine-5-carbonitrile, C31H25N5O3, (III), crystallizes in the unsolvated form. The heterocyclic components of (I) are linked by C—Hπ(arene) hydrogen bonds to form cyclic centrosymmetric dimers, from which the solvent molecules are pendent, linked by N—HO hydrogen bonds. In (II), the heterocyclic components are linked by a combination of C—HN and C—Hπ(arene) hydrogen bonds into chains containing two types of centrosymmetric ring, and the pendent solvent molecules are linked to these chains by N—HO hydrogen bonds. Molecules of (III) are linked into simple C(12) chains by an N—HO hydrogen bond, and these chains are weakly linked into pairs by an aromatic π–π stacking interaction.
organic compounds
In the title compound, C13H10O4, prepared by the condensation reaction between phthalic anhydride and pentane-2,4-dione, one of the acetyl groups in the pentane-2,4-dione fragment is almost coplanar with the isobenzofuran ring system, while the other group is twisted out of this plane by almost 80°. The corresponding C-C and C-O distances in the two acetyl units are consistent with dipolar delocalization into the coplanar unit only. There is no supramolecular aggregation of the molecules, but a number of rather short intermolecular contacts of C-HO, OO and OC types occur.
organic compounds
In both 2,5-dimethyl-6,7-dihydrobenzo[h]pyrazolo[1,5-a]quinazoline, C16H15N3, (I), and 2-tert-butyl-5-methyl-6,7-dihydrobenzo[h]pyrazolo[1,5-a]quinazoline, C19H21N3, (II), which crystallizes with Z' = 2 in the space group P, the non-aromatic carbocyclic rings adopt screw-boat conformations. The molecules of (I) are linked into chains of rings by a combination of C-HN and C-H(arene) hydrogen bonds, while in (II) there are no hydrogen bonds of any kind.
organic compounds
In the title compound, C10H19NO6, both rings adopt almost perfect chair conformations and their mutual orientation is influenced by an intramolecular O—HN hydrogen bond. The molecules are linked by three independent O—HO hydrogen bonds into sheets containing equal numbers of R22(10) and R44(24) rings.
organic compounds
In methyl 4-(5-amino-3-phenyl-1H-pyrazol-1-yl)-3-nitrobenzoate, C17H14N4O4, the molecules are linked into complex sheets by a combination of N-HN, N-HO and C-HO hydrogen bonds. In the isomeric methyl 3-nitro-4-[(5-phenyl-1H-pyrazol-3-yl)amino]benzoate, molecules exhibit a polarized molecular-electronic structure and are linked into chains of edge-fused rings by a combination of N-HO and C-HO hydrogen bonds.
organic compounds
The title compound, C30H26ClN3, crystallizes with Z' = 3 in the P space group. The three independent molecules have very similar, although not identical, conformations, with almost perfect screw-boat forms adopted by the non-aromatic carbocyclic rings. Four independent C-H(arene) hydrogen bonds link the molecules into centrosymmetric six-component aggregates.
organic compounds
In the title compound, C8H12N+·C4H3O4−, there is a short and almost linear but asymmetric O—HO hydrogen bond in the anion. The ions are linked into C22(6) chains by two short and nearly linear N—HO hydrogen bonds and the chains are further weakly linked into sheets by a single C—HO hydrogen bond.
organic compounds
The title compound [systematic name: 6-amino-5-formyl-1,3-dimethylpyrimidine-2,4(1H,3H)-dione monohydrate], C7H9N3O3·H2O, has been reexamined at 120 K. The improved precision of the intramolecular dimensions provides evidence for a polarized molecular–electronic structure, and the molecular components are linked by one N—HO and two O—HO hydrogen bonds into two interwoven three-dimensional frameworks, which are weakly linked by the longer component of a three-centre N—H(O)2 hydrogen bond.
organic compounds
The molecules of 2-amino-4,6-bis[N-methyl-N-(4-methylphenyl)amino]pyrimidine-5-carbaldehyde, C21H23N5O, (I), and 2-amino-4-(indolin-1-yl)-6-methoxypyrimidine-5-carbaldehyde, C14H14N4O2, (II), which crystallizes with Z' = 2 in the space group P, exhibit polarized electronic structures. Molecules of (I) are linked by a combination of N-HO, C-HO and C-H(arene) hydrogen bonds into a three-dimensional framework structure, while those of (II) are linked into sheets by a combination of two N-HO hydrogen bonds and one N-H(arene) hydrogen bond.
organic compounds
The molecular dimensions of both 2-amino-6-(N-methylanilino)pyrimidin-4(3H)-one, C11H12N4O, (I), and 2-amino-6-(N-methylanilino)-5-nitropyrimidin-4(3H)-one, C11H11N5O3, (II), are consistent with considerable polarization of the molecular-electronic structures. The molecules of (I) are linked into a three-dimensional framework by a combination of one N-HN hydrogen bond, two independent N-HO hydrogen bonds and one C-H(arene) hydrogen bond. The molecules of (II) are linked into ribbons containing three types of edge-fused ring by the combination of two independent three-centre N-H(O)2 hydrogen bonds.
organic compounds
In the title compound, C23H24N4O3, the pyrimidine ring adopts an almost perfect boat conformation, and the bond distances provide evidence for some polarization of the molecular-electronic structure. Two independent N-HO hydrogen bonds link the molecules into chains of edge-fused R24(8) and R22(20) rings.