Efficient synthesis of novel furo[2,3-d]pyrimidine derivatives under catalyst-free conditions.

A series of furo[2,3- d ]pyrimidine derivatives were synthesized via the [3+2] cyclization of pyrimidine-4,6-diol and a variety of nitroolefins at catalyst-free conditions. The reaction is easy to perform simply mixing inexpensive starting materials in water under conventional heating at 90 °C. The reaction proceeds at a fast speed within 1.5–2 h and gives the high biological and pharmacological active substituent furo[2,3- d ]pyrimidine derivatives with good to high yields. Mechanism of formation of these furo[2,3- d ]pyrimidine derivatives are also proposed. [ABSTRACT FROM AUTHOR]