6-Cyanouracil derivatives underwent a direct nucleophilic substitution reaction with alkyl Grignard reagents in the presence of zinc(II) chloride as a catalyst to form the corresponding 6-alkyluracils. This methodology is applicable to sugar-protected 6-cyanouridine and 6-cyano-2'-deoxyuridine without the protection at the N-3-imide and provides a facile and general access to versatile 6-alkyluracil and 6-alkyluridine derivatives.
Research on Antiviral Agents. 5. Lithiation of 6-Methyluracil as a New and Efficient Entry to C(6)-Substituted Uracils
作者:Raffaele Saladino、Maurizio Botta、Giuliano delle Monache、Gabriella Gentile、Rosario Nicoletti
Cycloaromatization of α-oxoketene dithioacetals with enaminone derived carbanions
作者:Janagani Satyanarayana、Kethiri R. Reddy、Hiriyakkanavar Ila、Hiriyakkanavar Junjappa
DOI:10.1016/s0040-4039(00)60035-7
日期:1992.10
Lithium enolates 3b and 6b derived from 1,3,6-trimethyluracil (3a) and 3-pyrrolidinocrotonate (6a) undergo regioselective gamma-1,4- and gamma-1,2-additions respectively with alpha-oxoketene dithioacetals 7 to yield the corresponding quinazolines and amino substituted aromatic compounds after subsequent cycloaromatization.
Photocycloaddition of 6-chloro-1,3-dimethyluracil to alkenes: synthesis of 1,2-dihydrocyclobuta[]pyrimidine-4,6 (3H, 5H)-diones