The synthesis of new derivatives of 3-azabicyclononan is one of the urgent tasks of modern synthetic organic chemistry. 3-Azabicyclononan is a structural analogue of the cytisine alkaloid, which is a strong agonist of acetylcholine receptors. Among synthetic heterocycles containing a 3-azabicyclo[3.3.1]nonane fragment, compounds with different types of biological activity have been discovered at present: analgesic, anti-inflammatory, antimicrobial, antioxidant, and others. The introduction of a fragment of azabicyclononan into the amino acid structure can lead to a limitation of the conformational mobility of a new molecule, as a result of which the activity and selectivity of its interaction with the receptor will increase. We synthesized 2-(1,9-dinitro-8-oxo-6,11-diazatricyclo[7.3.1.02,7]trideca-2,4,6-trien-11-yl)acetic acid and 2-(1,9-dinitro-8-oxo-13-(2-oxopropyl)-6,11-diazatricyclo[7.3.1.02,7]trideca-2,4,6-trien-11-yl)acetic acid by the interaction of annionic σ-complexes 5,7-dinitro-8-hydroxyquinoline with glycine under Mannich condensation in high yield. At the beginning, when 5,7-dinitro-8-hydroxyquinoline NaBH4 was applied in DMF or acetone carbanion in DMSO, the corresponding anionic complexes were synthesized. The resulting adducts were isolated from the reaction mixture, dissolved in cold water, and an aminomethylating mixture consisting of formaldehyde and an amino acid was added. As a result, 3-azabicyclo[3.3.1]nonane derivatives are formed, annelated with a pyridine ring and containing an amino acid residue. By the methods of NMR and IR spectroscopy, as well as high-resolution mass spectrometry, the structure of the obtained compounds was proved. Thus, in the 1H NMR spectra of the synthesized compounds, a signal of the proton of the carboxyl group in the form of a broadened singlet is detected in a weak spectral region. Equatorial and axial protons of an alicyclic fragment form a characteristic system of signals in the range δ 3.20-3.60 ppm. In the IR spectra of these molecules, the vibrational bands of carbonyl groups at ν 1720 cm–1, as well as the vibrational bands of the C–O bond of the carboxyl group at ν 1198 cm–1, are fixed. The m/z values in the high resolution mass spectra correspond to the molecular weights of the synthesized diazatricycclotridecans.

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Interaction between 5,7-dinitro-8-hydroxyquinoline hydride anionic σ-adduct and chlorides of substituted aryldiazonium in water yielded 5-arylazo-7-nitro-8-hydroxyquinolines, the substitution products of the nitro group at the C-5 σ-adduct position. The direction of the reaction agrees with the quantum-chemical calculations carried out earlier and the GMLA principle, which assumes that the mild acid, which is a diazocathione, will attack the reaction center to which the softest base corresponds, that is, the least negatively charged C-5 carbon atom, in contrast to the C-7 atom. It is shown that the yield of the product increases with the presence of an electron-withdrawing substituent in the diazocomponent. Also in this study, the synthesis of the hydride σ-adduct of 5,7-dinitro-8-hydroxyquinoline was optimized. It was found that the use of pure dimethylacetamide as a solvent, as well as the addition of sodium carbonate, increases the yield and purity of the synthesized σ-adduct. The structure of the obtained compounds was proved by the methods of NMR and IR spectroscopy. In the IR spectra of all synthesized azo compounds, weak absorption bands corresponding to the stretching vibrations of the azogroup (N = N) are fixed in the range of 1400-1465 cm-1, which also indirectly confirms the expected direction of the reaction. Otherwise, the bands of the azogroup vibrations would be shifted to the 1500-1600 cm-1 region as a result of azo-hydrazoic tautomerism. In 1H NMR spectra of synthesized compounds, there is no proton signal of intramolecular hydrogen bond at δ 14-15 ppm, characteristic of the hydrazine form. The proton signals of the arylazo group also confirm the presence of the latter. The use of anionic hydride σ-complexes of dinitroquinoline derivatives as azo-component in the reaction with aromatic diazo compound expands the synthetic possibilities of the azo coupling reaction and allows to obtaine new nitroazoquinolines.

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