Center for AIDS Research, Laboratory of Biochemical Pharmacology, Department of Pediatrics, Emory University School of Medicine , and Veterans Affairs Medical Center, Decatur, Georgia 30033, United States, and RFS Pharma, LLC , 1860 Montreal Road, Tucker, Georgia 30084, United States.
Org Lett. 2012 May 18;14(10):2488-91. doi: 10.1021/ol300777p. Epub 2012 May 3.
An efficient protection protocol for the 6-exo-amino group of purine nucleosides with various chloroformates was developed utilizing N-methylimidazole (NMI). The reaction of an exo-N(6)-group of adenosine analogue 1 with alkyl/and aryl chloroformates under optimized conditions provided the N(6)-carbamoyl adenosines (2a-j) in good to excellent yields. The reaction of N(6)-Cbz-protected nucleosides (5a-c) with phenyl phosphoryl chloride (7) using t-BuMgCl followed by catalytic hydrogenation afforded the corresponding phosphoramidate pronucleotides (8a-c) in excellent yield.
开发了一种利用 N-甲基咪唑 (NMI) 保护嘌呤核苷 6-外氨基的有效保护基方法,可与各种氯甲酸酯反应。在优化条件下,阿糖腺苷类似物 1 的外 N(6)-氨基与烷基/芳基氯甲酸酯反应,以良好至优异的收率得到 N(6)-氨甲酰腺苷 (2a-j)。用 t-BuMgCl 使 N(6)-Cbz 保护的核苷 (5a-c) 与苯膦酰氯 (7) 反应,然后催化氢化,可得到相应的磷酰胺酯前核苷 (8a-c),产率优异。