Notes: N2-Isobutyryl guanosine is a derivative of the nucleoside guanosine (Item No. 27702) containing an isobutyryl protecting group.{66625} It is a precursor in the synthesis of hydrophobic dinucleotide cap analogs used to purify capped mRNA and photocaged 3’-S-RNAs used in the study of ribozyme-catalyzed reactions.{66625,66626}