Table 2.

Efficiency of the UV (365 nm) irradiated uncaging of 2′-O-caged RNAs containing various 2′-O-photolabile groups.

2′-O-Caged RNAs	k (min−1)a	t1/2 (min)b	Time (min)c
2′-O-α-methyl-o-nitrobenzyl-RNA	3.0	0.23	0.83
2′-O-2-nitro-3,4-(MeO)2C6H3CH2-RNA	1.6	0.43	1.5–3
2′-o-nitrobenzyl-RNA	0.27	2.6	4–6

^ak is obtained from alkaline hydrolysis data of UV initiated uncaging of RNAs by fitting to the equation: y = y₀ – A*e^−kt.

^bt_1/2 is the time when 50% RNAs are uncaged.

^cTime estimated for full uncaging.