Synthesis of some biologically active 4-amino-1,2-dihydro-2-oxo/mercaptobenzofuro [3,2-d] pyrimidine derivatives via Dimroth rearrangement

Abstract

The condensation of 3-amino-2-benzofurancarbonitrile (I) with isocyanates and isothiocyanates gave 3-alkyl/aryl-4-iminobenzofuro [3,2-d] pyrimidine derivatives (II and IVa-e) which underwent Dimroth rearrangement in aq dimethyl formamide to yield 4-alkyl/arylamino-1,2-dihydro-2-oxo/mercaptobenzofuro [3,2-d] pyrimidine derivatives (III and Va-e). The biological activities of the title compounds have been described.