A new and practical method for the synthesis of 1-and 1, 3-substituted xanthines is reported. Direct base-promoted condensation of the imidazole precursor 1 with carbamates 2 gives 1- substituted 7-PMB xanthines 7 in good yields. Alkylation of these derivatives or their potassium salts proceeds under mild conditions to give functionalized 1, 3-substituted 7- PMB xanthines 9 in good to excellent yields. The obtained 7-PMB-protected derivatives ...
![1-ethyl-7-[(4-methoxyphenyl)methyl]-3H-purine-2,6-dione Structure](https://image.chemsrc.com/caspic/258/630413-93-3.png)
