@misc{Stasiewicz-Urban_Anna_Synthesis_2007,
 author={Stasiewicz-Urban, Anna},
 address={Kraków},
 howpublished={online},
 year={2007},
 school={Wydział Farmaceutyczny},
 language={pol},
 abstract={This work is an attempt to clarify the knowledge about the physicochemical properties of carbonyl groups of 2,4,6(1H,3H,5H)-pyrimidinetrione ring, which is the structural framework of the barbiturates. The experiment of tionation of barbiturates with different substituents was run using the Lawesson's reagent. These reactions proved a significant influence of steric hidrance of substituents in the C(5) position on results of the tionation reaction, which is at variance with theoretical calculations suggesting that the carbonyl group in the 2 position is the most polarized part of barbiturate molecule. Therefore, the hypothesis was formulated that in barbiturates the largest electropositive charge is located on carbon atom of carbonyl groups. It was proved, that chemical shifts of thiocarbonyl atoms in 13C NMR spectra of thiobarbiturates are in the same sequence as m the spectra of barbiturates. According to this observation, the desulfurization reactions of 2,4-ditio and tritiobarbiturates using NH3 and NO+ was performed. The results of these reactions confirm that the carbon atom in position 4(6) is the place of reaction with the nucleophilic agent NH3. The electrophilic agent more readily reacts with sulfur atom ofthiocarbonyl group in position 2. The influence of amount and position of thiocarbonyl group on spectral properties of thiobarbiturates was also studied in details.},
 title={Synthesis of the thioderivatives of barbiturates, their physicochemical properties and reactivity of the (thio)carbonyl groups},
 type={Praca doktorska},
 keywords={Lawesson's reagent, thiobarbiturates, barbiturates, 13C NMR spectroscopy of thiocarbonyl groups},
}