The Synthesis of oligoribonucleotides—IV : Preparation of dinucleoside phosphates from 2′,5′-protected ribonucleoside derivatives

摘要: Abstract The preparation of 2′-O-tetrahydropyranyl-uridine and -adenosine is described. Both diastereoisomers each derivative have been isolated in a pure crystalline state. high-melting (more laevorotatory) diastereoisomer derived form nucleoside has converted to its 5′-O-pivaloyl derivative. 2′-O-tetrahydropyranyl-5′-O-pivaloyluridine independently prepared from 3′-O-acetyl-′-O-pivaloyluridine, condensed with 2′,3′-O-methoxymethylideneuridine 5′-phosphate, thereby into uridylyl-(3′ → 5′)-uridine good yield. 2′-O-tetrahydropyranyl protecting group may be removed by acidic hydrolysis (with 0-01N HCI) under very mild conditions which lead negligible amount isomerization (by phosphoryl migration) degradation the dinucleoside phosphate. Each phosphate: adenylyl -(3′ 5′)-uridine, 5′)-adenosine, 5′)-cytidine adenylyl-(3′ also same way appropriate 2′-O-tetrahydropyranyl-5′-O-pivaloyl nucleoside.