5′-O-[[[6-[[2-(4,4-Dimethyl-2,5-dioxo-1-imidazolidinyl)acetyl]amino]hexyl]oxy]hydroxyphosphinyl]thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidine

5′-O-[[[6-[[4-[(2,5-Dioxo-1-imidazolidinyl)methyl]benzoyl]amino]hexyl]oxy]hydroxyphosphinyl]thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidine

5′-O-[[[6-[[3-[(2,5-Dioxo-1-imidazolidinyl)methyl]benzoyl]amino]hexyl]oxy]hydroxyphosphinyl]thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidine

5′-O-[[[6-[[3-(2,5-Dioxo-4-imidazolidinyl)-1-oxopropyl]amino]hexyl]oxy]hydroxyphosphinyl]thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidine

5′-O-[[[6-[[2-(2,5-Dioxo-4-imidazolidinyl)acetyl]amino]hexyl]oxy]hydroxyphosphinyl]thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidine

5′-O-[[[6-[[3-(1,3-Dihydro-1,3-dioxo-2H-isoindol-2-yl)-1-oxopropyl]amino]hexyl]oxy]hydroxyphosphinyl]thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidine

5′-O-[[[6-[[(2,3-Dihydro-2,3-dioxo-1H-indol-5-yl)carbonyl]amino]hexyl]oxy]hydroxyphosphinyl]thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidine

5′-O-[[[6-[[(2,3-Dihydro-2,3-dioxo-1H-indol-7-yl)carbonyl]amino]hexyl]oxy]hydroxyphosphinyl]thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidine

5′-O-[[[6-[[2-[6-(Aminosulfonyl)-2-oxo-3(2H)-benzoxazolyl]acetyl]amino]hexyl]oxy]hydroxyphosphinyl]thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidine

5′-O-[Hydroxy[[6-[[1-oxo-3-(2-oxo-3(2H)-benzoxazolyl)propyl]amino]hexyl]oxy]phosphinyl]thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidine

5′-O-[[[6-[[2-(1,2-Dihydro-5,7-dimethyl-2-oxopyrazolo[1,5-a]pyrimidin-6-yl)acetyl]amino]hexyl]oxy]hydroxyphosphinyl]thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidine

5′-O-[[[6-[[2-(1,3-Dihydro-3-oxo-2H-indazol-2-yl)acetyl]amino]hexyl]oxy]hydroxyphosphinyl]thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidine

5′-O-[[[6-[[(2,5-Dihydro-5-oxo-1H-pyrazol-3-yl)carbonyl]amino]hexyl]oxy]hydroxyphosphinyl]thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidine

5′-O-[[[6-[[(2,3-Dihydro-1,6-dimethyl-3-oxo-1H-pyrazolo[3,4-b]pyridin-4-yl)carbonyl]amino]hexyl]oxy]hydroxyphosphinyl]thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidine

5′-O-[[[6-[[(6-Cyclopropyl-2,3-dihydro-1-methyl-3-oxo-1H-pyrazolo[3,4-b]pyridin-4-yl)carbonyl]amino]hexyl]oxy]hydroxyphosphinyl]thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidine

5′-O-[[[6-[[2-(2,3-Dihydro-2-oxo-1H-benzimidazol-1-yl)acetyl]amino]hexyl]oxy]hydroxyphosphinyl]thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidine

5′-O-[[[6-[[4-[[(2,3-Dihydro-2-oxo-1H-benzimidazol-5-yl)sulfonyl]amino]benzoyl]amino]hexyl]oxy]hydroxyphosphinyl]thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidine

5′-O-[[[6-[[(2,3-Dihydro-2-oxo-1H-benzimidazol-5-yl)carbonyl]amino]hexyl]oxy]hydroxyphosphinyl]thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidylyl-(3′→5′)-thymidine