Krasylov I. Synthesis and properties of linear (spiro)pyranocoumarins

The dissertation is devoted to the synthesis, modification and study of the chemical properties of (spiro)pyranocoumarins with a linear structure - analogues of the natural compound graveolone. Using the Cabé reaction, derived from the compounds 6-acetyl-7-hydroxy-4,8-dimethyl-2H-chromen-2-one and 6-acetyl-7-hydroxy-8-methyl-4-phenyl-2H-chromen- 2-one as starting compounds, using appropriate ketones, a number of (spiro)pyranocoumarins with cyclobutane, cyclopentane, cyclohexane, cyclohexanone, difluorocyclohexane, piperidine, and norbornanone spiro rings were obtained.The interaction of the obtained (spiro)pyranocoumarins with a linear structure with such a nucleophilic reagent as hydroxylamine hydrochloride was investigated. It is shown that even under harsh conditions, using a tenfold excess, the interaction occurs only at one exocyclic oxygen atom, forming the corresponding oximes. At the same time, the coumarin system remains intact in all cases, which is confirmed by NMR spectroscopy data. NMR with the Overhauser effect (NOESY) was performed to determine the configuration of the oxime group. Based on the obtained spectrum results, it can be assumed that the obtained oximes are in the E-coconfiguration.