New and practical method for synthesis of 1- and 1,3-substituted xanthines.
[reaction: see text] 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 can be readily deprotected to give the parent 1- and 1,3-substituted xanthines.
Zavialov
Ilia A
IA
Department of Synthetic Chemistry, Schering-Plough Research Institute, 1011 Morris Avenue, Union, New Jersey 07083, USA.
Dahanukar
Vilas H
VH
Nguyen
Hoa
H
Orr
Cecilia
C
Zhang
Fucheng
F
Andrews
David R
DR
D000478:Alkylation; D002219:Carbamates / Q000737:chemistry; D007093:Imidazoles / Q000737:chemistry; D014970:Xanthines / Q000138:chemical synthesis*
D002219:Carbamates; D007093:Imidazoles; D014970:Xanthines