2-Deoxy Sugars. VIII. Nucleosides Derived from 2-Deoxy-D-allopyranose (2-Deoxy-D-ribo-hexopyranose)¹

De Novo Asymmetric Synthesis of Homoadenosine via a Palladium-Catalyzed N-Glycosylation

“…In addition to displaying intriguing structures, they also possess distinct biological activities . Inspired by these natural products, chemists have made two hexopyranosyl nucleosides 2-deoxy-β- d - ribo -hexopyranose adenosine ( 1 ) and 2,3-dideoxy-β- d - ribo -hexopyranose adenosine ( 2 ) . These homologous nucleosides of adenosine and deoxyadenosine possess obvious structural and configurational similarities to the corresponding ribofuranose adenosines 3 and 4 (Figure ).…”

“…These homologous nucleosides of adenosine and deoxyadenosine possess obvious structural and configurational similarities to the corresponding ribofuranose adenosines 3 and 4 (Figure ). Biological studies of these ring-expanded analogues ( 1 and 2 ) have led to the discovery of several pyrano-nucleotide analogues with both antitumor and antiviral activity. − The interest in analogues of 3 and 4 has also led to the development of many novel nucleoside structures with anticancer and/or antiviral activity 1 Adenosines and hexopyranosyl nucleosides. …”

“…The 2-deoxy-β- l - ribo -hexopyranose ( ent )-1 was synthesized only in six steps and 2,3-dideoxy-β- l - ribo -hexopyranose ( ent )-2 was prepared in five steps from Boc-protected pyranone (nine and eight steps from an achiral acylfuran, respectively). In addition to being the first synthesis of the l -sugar forms of 1 and 2 , this synthesis is the first to diastereoselectively install the purine base at the anomeric center. − The synthesis of other potential analogues and evaluation of the biological activity of these compounds are ongoing.…”