Synthesis of N‐Substituted‐6‐alkoxypteridin‐4‐amine

A novel seven‐step methodology for the synthesis of N ‐substituted‐6‐alkoxypteridin‐4‐amine has been developed with the total yields of 35.4–41%. Twenty new compounds were synthesized by heterocyclization of easily prepared 3‐amino‐6‐bromopyrazine‐2‐carboxamide, subsequent alkoxylation, chlorination, and nucleophilic substitution. Their structures were confirmed by 1 H‐NMR, 13 C‐NMR, ESI‐MS, and elemental analysis. The structure of N ‐(3‐chloro‐4‐fluorophenyl)‐6‐ethoxypteridin‐4‐amine was further determined by X‐ray crystallographic analysis. It was found that different chlorinating reagents gave different products. The possible chlorination mechanism was discussed.