Stereoselective Syntheses of 3'-Hydroxyamino- and 3'-Methoxyamino-2',3'-Dideoxynucleosides
Sritama Bose1, David R W Hodgson1
1Durham University , Department of Chemistry , Lower Mountjoy, Stockton Road , Durham , DH1 3LE , United Kingdom.
Abstract:
Aminonucleosides are used as key motifs in medicinal and bioconjugate chemistry; however, existing strategies toward 3'-hypernucleophilic amine systems do not readily deliver deoxyribo-configured products. We report diastereoselective syntheses of deoxyribo- and deoxyxylo-configured 3'-hydroxyamino- and 3'-methoxyamino-nucelosides from 3'-imine intermediates. The presence or absence of the 5'-hydroxyl-group protection dictates facial selectivity via inter- or intramolecular delivery of hydride from BH3 (borane). Protecting group screening gave one access to previously unknown 3'-methoxyamino-deoxyguanosine derivatives.
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