Uracils: versatile starting materials in heterocyclic

Wamhoff, H., Dzenis, J., Hirota, K., Uracils Versatile Starting Materials in Heterocyclic Synthesis, 55, 129. 

Uracils Versatile Starting Materials in Heterocyclic Synthesis. 55, 129. 

A lot of information about the structure, reactivity, and the best synthetic approaches for pyrimidopyrimidines has been described in CHEC-I. Additionally, some new methods of preparation of pyrimidopyrimidines have been reported in reviews on the synthesis of fused pyrimidines by Delia and Warner starting material in heterocyclic synthesis by Wamhoff, Dzenis, and Hirota <92AHC(55)129>. Pyrimidopyrimidines are especially interesting as structural analogues of natural compounds. 

In addition to these aforementioned fundamental reactions on the intact uracil molecule, suitable substituted uracil derivatives have proven to be versatile starting materials of typical synthon character, leading to novel condensed heterocyclic systems consisting of two, three, and more heterocyclic rings. Many of these possess great biological interest [antibiotics,... 

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