建立了区域选择性核糖基化条件,该条件可同时生成6,7-二氯-1-(2,3,5-三-O-苯甲酰基-β-D-核呋喃呋喃糖基)咪唑并[4,5 - b ]喹啉-2-酮(4)和6,7-二氯-3-(2,3,5-三- ø -苯甲酰-β-d-D-呋喃核糖基)咪唑并[4,5-b]喹啉-2-酮(5),分别在高由6,7-二氯咪唑并[4,5- b ]喹啉-2-酮(6)得到。讨论了在各种条件下核糖基化位点的分布。
Synthesis and Regioselective Ribosylation of 6,7-Dichloroimidazo[4,5-b]quinolin-2-one
摘要:
The polyhalogenated benzimidazole nucleosides 2,5,6-trichloro-1-(beta-D-ribofuranosyl)benzimidazole (TCRB) and the 2-bromo analogue (BDCRB) were synthesized in our laboratory and established as potent and selective antiviral agents against human cytomegalovirus (HCMV) with a novel mode of action. In an effort to study the behavior of the key substructure of these analogues in a dimensionally stretched-out manner and probe the spatial limitation of the target enzyme(s), a series of N1- and N3-ribonucleosides of imidazo[4,5-b]quinolines were designed as linear dimensional analogues. The nucleosides 6,7-dichloro-1-(beta-D-ribofuranosyl)imidazo[4,5-b]quinolin-2-one and 6,7-dichloro-3-(beta-D-ribofuranosyl)imidazo[4,5-b]quinolin-2-one were selected and prepared as the key intermediates in this study. During this study, a novel photoassisted annulation was developed for the synthesis of 6,7-dichloroimidazo[4,5-b]quinolin-2-one, which overcame several problems that were encountered with the literature annulation method. Regioselective ribosylations of this heterocycle were developed and gave both the N1 and the N3 isomers in high yield.
A novel photo-assisted annulation reaction for the synthesis of 6,7-dichloroimidazo[4,5-b]quinolin-2-one
作者:Zhijian Zhu、Blaise S. Lippa、Leroy B. Townsend
DOI:10.1016/0040-4039(96)00308-5
日期:1996.3
A novelphoto-assistedannulation was developed for the synthesis of 6,7-dichloroimidazo[4,5-b]quinolin-2-one. This mild ring closure method has circumvented problems associated with the previous methods and should tolerate a variety of functional groups.