Synthesis of uridine and 2′-deoxyuridine mono- and tri-phosphates alkylated in position 5 by glycosides of α-D-mannose and N-acetyl-β-D-glucosamine: DNA and RNA monomers with tethered lectin targets
Abstract
A simple synthesis of deoxyuridine and uridine 5′-mono- and 5′-tri-phosphates, C-5 alkylated by glycosides of 2-acetamido-2-deoxy-β-D-glucopyranose and α-D-mannopyranose, is reported. The glycosides (5) and (7) have been obtained respectively, by condensation of 3,4,6-tri-O-acetyl-1,2-dideoxy-1,2-dihydro-2′-methyl-α-D-glucopyranoso[2,1 -d]-oxazole (2), and tetra-O-benzoyl-α-D-mannopyranosyl bromide (3) with 6-(N-acryloylamino)hexan-1-ol (1) as aglycone. These two glycosides were then coupled to the C-5 position of dUMP and UMP in the presence of Li2PdCI4 to give compounds (15)–(18) in 30–45% yield. Their structure and those of the by-products (13), (14), (22), and (23) were determined by mass and NMR spectroscopies. The same reaction was successfully applied to the synthesis of triphosphate analogues (19)–(21) in 14–19% yield.