Microwave-assisted synthesis of pyrimidine libraries

Di- and trisubstituted pyrimidine libraries are prepd. in good yields by the microwave irradn. of an alkynone R1C≡CCOR2 [R1 = H, Ph; R2 = Ph, 4-MeOC6H4, 3,4-(MeO)2C6H3, etc.] and either an amidine or guanidine at 120-150° in acetonitrile in the presence of sodium carbonate or at 100° after treatment with methanolic sodium methoxide in a sealed tube using a monomodal microwave synthesizer. These rapid and efficient methods often require no chromatog. purifn. and so are appropriate for automated combinatorial methodol. and have been applied in the synthesis of a small library of potentially useful novel ligands for the estrogen receptor based on the pyrimidine template