Patent ID: 7019128

Claim:
A method for performing a primer extension reaction comprising: annealing a polynucleotide primer to a portion of a template nucleic acid, and extending the annealed primer in the presence of a compound having the structure: wherein: n is 1 or 2, R1 and R2 taken separately are each selected from —H, lower alkyl, protecting group and label, B is a 7-deazapurine, purine, or pyrimidine nucleoside base, wherein when B is purine or 7-deazapurine, the sugar moiety is attached at the N9-position of the purine or deazapurine, and when B is pyrimidine, the sugar moiety is attached at the N1-position of the pyrimidine, and wherein if B is a purine, the adjacent triple-bonded carbon is attached to the 8-position of the purine, if B is 7-deazapurine, the adjacent triple-bonded carbon is attached to the 7-position of the 7-deazapurine, and if B is pyrimidine, the adjacent triple-bonded carbon is attached to the 5-position of the pyrimidine, W1 is selected from —H and —OH, W2 is —OH or a moiety which renders the nucleoside incapable of forming a phosphodiester bond at the 3′-position, and W3 is selected from —PO4, —P2O7, —P3O10, phosphate analog, and —OH, whereby an extended primer is formed comprising at least one of the compound.