A new and efficient synthesis of substituted 6-[(2'-dialkylamino)ethyl] pyrimidine and 4-N,N-dialkyl-6-vinyl-cytosine derivatives and evaluation of their anti-rubella activity.

New 6-[(2'-dialkylamino)ethyl]-4(3H)-pyrimidinones were prepared by a multistep procedure starting from acetone dicarboxylic acid diethyl ester and urea derivatives. These compounds were used as starting materials to obtain 4-N,N-dialkyl-6-vinyl-pyrimidine derivatives by an unprecedented tandem C-6 side chain Hofmann-like elimination/C-4 pyrimidinone substitution. Among the new derivatives obtained, various compounds show anti-Rubella activity. The inhibition of HIV-1 Reverse Transcriptases (RT), from both wild type and modified viruses, is also reported.