A New Strategy To Construct Acyclic Nucleosides via Ag(I)-Catalyzed Addition of Pronucleophiles to 9-Allenyl-9H-purines
摘要:
A new strategy to construct acyclic nucleosides with diverse side chains was developed. With Ag(I) salts as catalysts, the hydrocarboxylation, hydroamination, and hydrocarbonation reactions proceeded well, affording acyclic nucleosides in good yields (41 examples, 60-98% yields). Meanwhile, these reactions exhibited high chemoselectivities and E-selectivities.
Design and Synthesis of Nucleoproline Amino Acids for the Straightforward Preparation of Chiral and Conformationally Constrained Nucleopeptides
作者:Rolf A. Kramer、Konrad H. Bleicher、Helma Wennemers
DOI:10.1002/hlca.201200557
日期:2012.12
A straightforwardsynthesis of orthogonally protected nucleoproline (Nup) aminoacids and their coupling to oligomers are described. A key step is the attachment of alkynylated nucleobases to Fmoc‐protected 4‐azidoproline (Fmoc‐Azp‐OH) by a Cu‐catalyzed 1,3‐dipolar cycloaddition (‘click reaction’). The developed protocol allows preparation of the nucleoprolines in scales of >30 g. Solid‐phase peptide