Selective Synthesis of 7-Substituted Purines via 7,8-Dihydropurines
摘要:
A simple and efficient protocol for the preparation of 7-substituted purines is described. 6- and 2,6-Dihalopurines were N-9-tritylated and then transformed to 7,8-dihydropurines by DIBAL-H. Subsequent N-7-alkylation followed by N-9-trityl deprotection with trifluoroacetic acid was accompanied by spontaneous reoxidation, which led to the 7-substituted purines at 55-88% overall isolated yields.
Perfluoroalkylation of 6-Iodopurines by Trimethyl(perfluoroalkyl)silanes. Synthesis of 6-(Perfluoroalkyl)purine Bases, Nucleosides and Acyclic Nucleotide Analogues
Using regioselective cuprations (via magnesiations), various primary, secondary and tertiary aminated pyrimidine and purinederivatives were prepared by the oxidative coupling of lithium amidocuprates using chloranil. DNA and RNA units such as aminated uracil or thymine, and adenine, as well as a CDK inhibitor, purvalanol A, were all obtained under mild conditions and satisfactory yields.