Synthesis of Highly Substituted Imidazole Uracil Containing Molecules via Ugi-4CR and Passerini-3CR.

The synthesis of uracil/thymine containing tetra/trisubstituted imidazole derivatives was demonstrated using Ugi/Passerini-reaction followed by a postcyclization reaction sequence. The approach enables the one-pot facile construction of diverse compounds in moderate to excellent yields (47-82%). The 5-fluorouracil and 5-methyluracil moieties afford potentially bioactive molecules with drug-like properties. These scaffolds are currently being utilized in the screening deck of the European Lead Factory.