Ureas 5-nitrobarbiturate

The fuels are, for example, 5-aminotetrazole, azodicarbonamide, -> Guanidine nitrate, -> Nitroguanidine, dicyandiamide, -> Triamino-guanidine nitrate and similar compounds, as well as salts of, for example, 5-nitrobarbituric acid, urea derivatives and also nitra-mines and similar compounds. The oxidisers are, for example, alkali or alkaline earth nitrates, -> Ammonium, alkali or alkaline earth perchlorates and metal oxides. 

Nitrobarbituric acid (also named dilituric acid or 5-nitro-2,4,6-trihydroxypyrimidine), formally a cyclic urea derivative, is selected as a host component [25]. In the solid state 5-nitrobarbiturate has the tendency to form a dimer, and three kinds of possible linkage are designated as types A, B and C, as illustrated in Scheme 8.1. Among these. 

Scheme 8.2 The nitrobarbiturate-urea connection modes found in hydrogen-bonded complexes type D (para shoulder-to-shoulder), type E (ortho shoulder-to-shoulder) and type F (head-to-tail)...

Centrosymmetric pairs of nitrobarbiturates and urea molecules are connected to form a tetramer (Figure 8.20) involving type E and F connection modes (Scheme 8.2). 

Versatile roles of (thio)urea in the 5-nitrobarbiturate inclusion systems... 

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