Figure 4. The left diagram shows the nucleoside selectivity calculated for pseudouridine by dividing the U-conjugate abundance by the Ψ-conjugate abundance.

All numbers below 1 present selectivity for uridine over pseudouridine and vice versa for all numbers above 1. In case of the main conjugates with 4-thiouridine the calculation includes the sum of all conjugates. In all cases conditions 1 lead to the highest overall selectivity for 4-thiouridine except for compound 3 where conditions 2 give the best selectivity.