Conformationally Locked Nucleoside Analogs. Synthesis of 2′-Deoxy-2′-C, 4′-C-Bridged Bicyclic Nucleosides
摘要:
1-alpha-Methylarabinose was converted, in three steps, to 2-deoxy-2-methyleneribose derivative 3, which was subjected to hydroboration to give 2-alpha-hydroxymethyl derivative 4 exclusively; 4 was converted to 2,4-bis(hydroxymethyl)ribose derivative 6 in four steps. Mesylation, detritylation, and ring closure, followed by hydrolysis of the mesyl group at O5, gave 3,6-dioxabicyclo[3,2,1]octane derivative 8. After acetylation, 8 was coupled with silylated 6-chloropurine to give desired alpha- and beta-bicyclic-sugar nucleosides.
Conformationally locked nucleosides. Synthesis and stereochemical assignments of 2′-C,4′-C-bridged bicyclonucleosides
摘要:
1-alpha-O-Methyl-3-O,5-O-TIPDS-arabinose was converted, in multiple steps, to 2,6-dioxabicyclo[3,2,1]octane derivatives, which were condensed with silylated nucleoside bases to give the desired 2',4'-bridged bicyclonucleosides. In this article, synthesis and stereochemical assignments of the bicyclonucleosides are described. (C) 1999 Elsevier Science Ltd. All rights reserved.