STUDIES ON PYRIMIDINE-ANNELATED HETEROCYCLES - SYNTHESIS OF PYRROLO [3,2-D] PYRIMIDINES BY AMINE OXIDE REARRANGEMENT

A number of pyrrolo[3,2-d]pyrimidine derivatives (5a-f) were synthesiz ed in 90-95% yields from the corresponding loxy)but-2-ynyl]-N-ethylami no]-1,3-dimethyluracils 4a-f by simple treatment with 1 equiv of m-chl oroperoxybenzoic acid in dichloromethane at 0-5 degrees C for 12-15 h. The resulting benzoates (5a-f) were easily converted to methoxy deriv atives 11a-f in 92-94% yields when refluxed in methanol for 20-22 h.