The asymmetric unit of the title compound, C(5)H(7)N(2) (+)·C(7)H(4)NO(4) (-)·C(7)H(5)NO(4), consists of an amino-pyridinium cation, a 4-nitro-benzoate anion and a neutral 4-nitro-benzoic acid mol-ecule. The pyridine ring forms dihedral angles of 64.70 (5)° and 70.37 (5)°, respectively, with the benzene rings of 4-nitro-benzoic acid and 4-nitro-benzoate. In the crystal structure, the cations, a...

The title compound, also known as 7-nitro-tropolone, C7H5NO4, exists in the crystalline state as the 2-hy-droxy-7-nitro-cyclo-hepta-2,4,6-trien-1-one tautomer and not as 2-hy-droxy-3-nitro-cyclo-hepta-2,4,6-trien-1-one. The dihedral angle between the ring and the nitro group is 70.3 (2)°. In the crystal, neighbouring mol-ecules are linked into dimers by a pair of O-H⋯O hydrogen bonds. In additi...

In the title compound, C(5)H(8)N(3) (+)·C(7)H(4)NO(4) (-)·C(7)H(5)NO(4), the non-H atoms of the 3,4-diamino-pyridinium cation are coplanar, with a maximum deviation of 0.022 (1) Å. The carboxyl-ate and nitro groups of the 4-nitro-benzoate anion are twisted out of the attached ring planes by dihedral angles of 15.89 (8) and 10.20 (8)°, respectively. In the 4-nitro-benzoic acid mol-ecule, the car...

The title compound, C(7)H(7)N(11)O(11) (PNMFIW), is a caged heterocycle substituted with five nitro and one formyl groups. It is related to the hexa-azaisowurtzitane family of high-density high-energy polycyclic cage compounds. Four nitro groups are appended to the four N atoms of the two five-membered rings, while a nitro group and a formyl are attached to the two N atoms of the six-membered r...

The straightforward access to a new class of aza-polyaromatics is reported. Starting from readily available fluorinated s-tetrazine, cyclization process with azide leads the formation an unprecedented tetrazo[1,2-b]indazole or bis-tetrazo[1,2-b]indazole (cis and trans conformers). Based on nitrogen core, further N-directed palladium-catalyzed ortho-C−H bond functionalization allows introduction...

Two classes of fused nitrogen heterocycles were designed as CK2 inhibitor candidates on the basis of previous structure-activity relationship (SAR) studies. Various dipyrrolo[3,2-b:2',3'-e]pyridine and benzo[g]indazole derivatives were prepared using transition-metal-catalysed cascade and/or multicomponent reactions. Biological evaluation of these candidates revealed that benzo[g]indazole is a ...

The structures of three NH-indazoles (3-methyl, 3-trifluoromethyl and 3-trifluoromethyl-4,5,6,7tetrafluoroindazoles) have been determined by X-ray crystallography. These three compounds, together with 3-methyl-4,5,6,7-tetrafluoroindazole, whose X-ray structure could not be determined, have been studied using multinuclear magnetic resonance spectroscopy, including solid-state CPMAS. They all are...

The title compound, C(2)H(8)N(+)·C(6)H(4)NO(3) (-)·C(6)H(5)NO(3), was synthesized from dimethyl-amine and 4-nitro-phenol in an overall yield of 85%. The dihdral angles between the nphenyl rings and their attached nitro groups are 5.7 (6) and 2.5 (7)°. In the crystal, there are strong hydrogen bonds between the ammonium group and the nitro-phenol and nitro-phenolate O atoms, and between the nitr...

A straightforward synthetic route to arylazoindazoles via nucleophilic aromatic substitution is presented. Upon deprotonation of the NH group, a C6F5-substituted formazan undergoes facile cyclization as a result of intermolecular nucleophilic substitution (SNAr). This new class of azo photoswitches containing an indazole five-membered heterocycle shows photochemical isomerization with high fati...