摘要：Some 6-mercaptopurine derivatives substituted at 8-position with hydrophilic groups such as -SH, -S-CH2-COOH, -CH2-CH2-COOH, -CH2OH, -COOH, and -NH-CH3 were synthesized for testing purine-antagonist action. They were prepared by the condensation of 4, 5-diamino-6-mercaptopyrimidine (I) with thiourea, succinic acid, glycolic acid, or ethyl oxalate, except in the case of 6-mercapto-8-methylaminopurine. In the condensation of (I) with oxalic acid, 7-aminothiazolo [5, 4-d] pyrimidine was directly obtained in considerable amount under alternative ring closure.
