| 摘要 |
The invention provides modified nucleotide or nucleoside molecule comprising a purine or pyrimidine base and a ribose or deoxyribose sugar moiety having a removable 3′-OH blocking group covalently attached thereto, such that the 3′carbon atom has attached a group of the structure—O—Z wherein Z is any of—C(R′)2-O—R″,—C(R′)2-N(R″)2,—C(R′)2-N(H)R″,—C(R′)2-S—R″and—C(R′)2-F, wherein each R″is or is part of a removable protecting group; each R′is independently a hydrogen atom, an alkyl, substituted alkyl, arylalkyl, alkenyl, alkynyl, aryl, heteroaryl, heterocyclic, acyl, cyano, alkoxy, aryloxy, heteroaryloxy or amido group, or a detectable label attached through a linking group; or (R′)2 represents an alkylidene group of formula═C(R′″)2 wherein each R′″may be the same or different and is selected from the group comprising hydrogen and halogen atoms and alkyl groups; and wherein said molecule may be reacted to yield an intermediate in which each R″is exchanged for H or, where Z is—C(R′)2-F, the F is exchanged for OH, SH or NH2, preferably OH, which intermediate dissociates under aqueous conditions to afford a molecule with a free 3′OH; with the proviso that where Z is—C(R′)2-S—R″, both R′groups are not H. |
