Two derivatives of barbituric acid, 5,5‐diethylbarbituric acid and 1,3‐dimethyl‐barbituric acid, were used to react with glycidol. The kinetics of reactions was studied by continuous determination of epoxide number and acidic number in the reaction mixture aliquots. Based upon the kinetic experiments, the rate equation was formulated, which was consistent with product spectral identification of the derivatives as well as with previously studied reaction of barbituric acid with glycidol. Reaction mechanisms of glycidol with methylene and imide groups of barbituric acid have been proposed.

The hydroxyalkyl derivatives of barbituric acid (BA) were formed in the reaction between BA and glycidol (GL). The reaction was performed at BA:GL 1:1, 1:2, and 1:4 molar ratios in DMF or without solvent. The progress of reaction was monitored by determination of the epoxide number and IR and NMR spectroscopy. It was found that primary reactive site of BA was C5 and further nitrogen ring atoms. BA was always involved in keto‐enol equilibrium, the latter form being less reactive. The isolated hydroxyalkyl derivatives are useful precursors of oligoetherols with the pyrimidine ring.

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Oligoetherols based on pyrimidine ring were obtained upon reaction of barbituric acid with glycidol and alkylene carbonates. These oligoetherols were then used to obtain polyurethane foams in the reaction of oligoetherols with isocyanates and water. The protocol of foam synthesis was optimized by the choice of proper kind of oligoetherol and synthetic composition. The thermal resistance was studied by dynamic and static methods with concomitant monitoring of compressive strength. The polyurethane foams have similar physical properties as the classic ones except their enhanced thermal resistance. They stand long-time heating even at 200°C. Moreover thermal exposition of foams results generally in increase of their compressive strength.