283168-85-4Relevant articles and documents
Synthesis of nitrogen bicyclic scaffolds: Pyrimido[1,2-a]pyrimidine-2,6- diones
Grosjean, Sylvain,Triki, Smail,Meslin, Jean-Claude,Julienne, Karine,Deniaud, David
scheme or table, p. 9912 - 9924 (2011/02/22)
The multi-step synthesis of 1,3,7-trisubstituted pyrimido[1,2-a] pyrimidinediones starting from isothiocyanates is described. These nitrogen bicycles were prepared by an iterative sequence of functionalization/ cyclocondensation reactions. [4+2] Cycloaddition reactions took place between diazadienic chains and various acyl chlorides providing sophisticated heterobicycles.
New 1,3-diazadienes used in heterocyclic synthesis
Friot, Celine,Reliquet, Alain,Reliquet, Francoise,Meslin, Jean Claude
, p. 695 - 702 (2007/10/03)
The synthesis of dihydropyrimidines, dihydropyrimidinones and thiadiazine-1,1-dioxides starting from neutral or cationic 2-methylthio-1,3- diazadienes is described. Addition of H2S followed by loss of methanethiol led to the corresponding thiocarbonyl compounds.