A general and efficient solid phase synthesis of quinazoline-2,4-diones

An efficient solid phase synthesis of chiral quinazolinediones is described Immobilized amino acid based urea derivatives 3 undergo a racemization-free heterocyclization upon gentle heating in presence of tetramethylguanidine to afford fused pyrimidine-2,4-diones 6, which are smoothly N-1-alkylated under mild conditions to produce immobilized quinazolinediones 8. The method is amenable to combinatorial synthesis and offers broad scope for structural and chemical diversity, as illustrated by preparation of fused thieno[2,3-d]pyrimidine-2,4-dione 10 and hydroxamate pharmacophore bearing quinazolinedione derivative 11. (C) 1997 Elsevier Science Ltd.