Synthesis of New Furo[2,3‐d]pyrimidines and Pyrimido[4′,5′:4,5]furo[2,3‐d]pyrimidines

Sodium salt of 4‐hydroxy‐6‐methyl‐2‐phenylpyrimidine‐5‐carbonitrile ( 3 ) was subjected to alkylation with different a‐halo compounds, where the corresponding O‐alkylated products 4_a‐g were obtained. Ring closure of the O‐alkylated product 4_a‐c performed using sodium ethoxide in refluxing ethanol afforded furo[2,3‐d]pyrimidines 5_a‐c The latter compounds on reaction with a variety of reagents gave other new furopyrimidines as well as a number of furodipyrimidines.