(8-Cyclopentyl-2,6-dioxo-1-propyl-3-(3-(tosyloxy)propyl)-3,4,5,6-tetrahydro-1H-purin-7(2H)-yl)methyl pivalate 1g

(8-Cyclopentyl-2,6-dioxo-1-propyl-3-(3-(tosyloxy)propyl)-3,4,5,6-tetrahydro-1H-purin-7(2H)-yl)methyl pivalate 1g