By reaction of dialkyl aminomalonates with formaldehyde were prepared 1,3,5-tris(dialkoxycarbonyimethyl)hexahydro-1,3,5-triazines that on nitration under mild conditions yielded the corresponding nitromethyl derivatives. The reaction of dialkyl aminomalonates with formaldehyde and polynitroalkanes operating as C-H acids results in Mannich bases. The latter were subjected to nitration with mixtures of sulfuric and nitric acids to afford dimethyl and diethyl 2,2,2-polynitroalkylnitroaminonitronialonates.