Syntheses of 3,8-dihydroxyimidazo[1,2-a]pyridines and [1,2-a]pyrazines

3,8-Dihydroxyimidazo [1,2-a] pyridines and [1,2-a]- pyrazines were prepared by condensation of glyoxal derivatives with methyl or benzyl ethers of 2-amino-3-hydroxypyridine and pyrazine followed by cleavage of the ether group